SERUM VITAMIN A AND NUTRITIONAL STATUS OF CHILDREN 
FED GARI AND BEANS STEW 
 
 
 
 
BY 
 
ALATIAH GABRIEL AJEDIWE 
(10358974) 
 
 
 
 
 
 
THIS THESIS IS SUBMITTED TO THE UNIVERSITY OF GHANA, 
LEGON IN PARTIAL FULFILMENT OF THE REQUIREMENT FOR 
THE AWARD OF MPHIL NUTRITION DEGREE 
 
 
 
JULY, 2013
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DECLARATION 
I, Alatiah Gabriel Ajediwe, author of this thesis ―Serum vitamin A and nutritional status of 
children fed gari and beans stew‖ do hereby declare that this thesis is the result of my own 
work carried out at the Department of Nutrition and Food Science, Faculty of Science, 
University of Ghana, under the supervision of Prof. Matilda Steiner-Asiedu and Dr. Kwesi 
Firibu Saalia. All references to other works have been duly acknowledged.  
 
 
 
……………………………………… 
Alatiah Gabriel Ajediwe 
    (Student) 
 
 
Date……………………………… 
 
 
 
………………………………….                               .............................................. 
Prof. Matilda Steiner-Asiedu           Dr. Kwesi Firibu Saalia 
         (Main Supervisor)                                                               (Supervisor) 
 
 
Date…………… ……………..                                   Date ……………………………..               
 
 
 
 
 
 
 
 
 
 
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DEDICATION 
This work is dedicated to my wife, Philomina and our three children, Awepiah, Aweniah 
and Achanah. 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
  
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ACKNOWLEDGEMENT 
My sincere appreciation goes to Our Lord Jesus Christ, the Almighty God, for His 
continuous shower of blessing upon my life. 
I am indebted to my supervisors Prof. Matilda Steiner-Asiedu and Dr. Kwesi Firibu Saalia 
for shaping my understanding of research and for their parental tutelage.  
I am also equally grateful to the other lecturers and staff of the Nutrition and Food Science 
Department for their patient and tireless efforts during my period of study. May the 
Almighty God reward their dedication hundred-fold.  
I appreciate the support Mr. Godfred Egbi has given during the study. I also extend a hand 
of appreciation to Nestle Nutrition Foundation for without you this study would not have 
been possible. 
I will like to sincerely express my appreciation to all of my family members for their 
continuous love and support. 
I am thankful to the Headmaster and staff and pupils of Kodzobi Basic school for all the 
support they rendered to me during the data collection.  
I am also grateful to the staff of the Nutrition Department of the Nugochi Memeorial 
Institute for Medical Research especially Mr. Clement Addo for their invaluable assistance 
during the data collection. 
I also owe my friends some gratitude. I am especially grateful to Mr. Emmanuel Mahama 
of the Kintampo Health Research Centre and Ms. Sika Kumordzi, Mr. Frederick Adiiboka 
and Ms. Cordula Abang all of the Nutrition and Food Science Department, University of 
Ghana. 
Finally, I am deeply appreciative of the profound support of my beloved wife, Philomina 
and the affection of our children, Awepiah, Aweniah and Achanah.  
  
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ABSTRACT 
Introduction: Vitamin A deficiency (VAD) is endemic among children in low income 
countries. Food-based strategies have been identified globally as more sustainable in 
addressing micronutrient deficiencies in populations. However, there is paucity of 
knowledge on the effect of food based interventions in combating vitamin A deficiency in 
Ghana. The objective of the present study was to determine the serum vitamin A and 
nutritional status of children fed gari and beans stew prepared with red palm oil. 
Methodology: The study was a 6 month one-group longitudinal pre - and - post - test 
design. A convenient sample of 142 school children (6 to 12 years) randomly selected at 
Kodzobi Basic School (Primary-JHS) in the Volta Region of Ghana participated in the 
study. A survey was conducted to determine the vitamin-rich foods in the community. A 
24 hour dietary recall and food frequency questionnaire instruments were employed to 
obtain information on the diet of the participants. The nutritional composition of the 
intervention diet was determined using a standard method. The β-carotene content of the 
diet and the serum retinol level of the participants were determined using High 
Performance Liquid Chromatographic (HPLC). The weight and height of the children 
were measured to determine weight-for-age z-scores, height-for-age z-scores and body 
mass index-for-age z-scores. Differences in means before and after the intervention period 
were determined using the paired t-test. Chi-squared test was used to examine the 
association between serum retinol and some categorical variables. Logistic regression 
models were used to explore the relationship between serum retinol and the background 
characteristics of study participants.  
Results: The survey revealed seasonal availability and accessibility of vitamin A-rich 
foods in the community. HPLC analysis of the intervention diet showed that it contained 
high vitamin A (823.56µg RE). Based on the 24 hour dietary recall the macronutrient 
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intakes between the pre and post interventions were significantly different. Carbohydrate 
intake pre-intervention was 357.76±56.50 g while the post intervention intake was 
411.36±58.99 g; pre-intervention protein intake was 31.86±8.43 g whereas the post 
intervention intake was 45.64±9.20 g. Fat intake pre-intervention was 33.52±7.20 g as 
against post intervention intake of 35.04±7.44 g. Median vitamin A intake increased from 
3.84 (0.0, 1392.14) µg RE to 4.61 (0.0, 1681.79) µg RE. None of the reported socio-
demographic variable showed a significant association with vitamin A status. The mean 
serum retinol level (12.13 µg/dL) of participants at pre-intervention was significantly 
different from the mean serum retinol of (16.11 µg/dL) at the post-intervention period, p 
<0.001. The prevalence of vitamin A deficiency (serum retinol concentrations < 20 µg/dL) 
among the participants decreased from 95.1% in pre-intervention to 77.5% in post-
intervention. Comparisons between the pre and post-intervention nutritional status showed 
a significant difference in height-for-age z-scores (p<0.001). However, there were no 
statistical differences between the pre and post intervention weight-for-age and BMI-for-
age z-scores (-2SD). Mean malaria parasite density for the pre intervention was 
2923.42±5667.09/µL and this was significantly different from the post intervention 
parasite density of 865.16±1312.12/µL. 
Conclusion: VAD is a public health challenge among the participants. The intake of 
vitamin A rich foods was poor due to seasonality and accessibility. There was high level 
of wasting and underweight among the participants. The intervention diet, gari and beans 
stew made with red palm oil served three times per week did improve serum retinol levels 
of the children and this may be a sustainable strategy in combating VAD. 
  
  
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LIST OF ACRONYMS AND ABBREVIATIONS 
µg                                      Microgram 
µg/dL                                  Microgram per dicilitre 
µg/g                                 Microgram per gram 
AED                                  Academy for Educational Development 
ALRI                                 Lower Respiratory Illnesses  
BAZ                                   Body Mass Index-for-age z-scores 
Cm                                        Centimeter 
FAO                              Food and Agricultural Organization 
FFQ     Food Frequency Questionnaire 
g            Gram 
GDHS                            Ghana Demographic and Health Survey 
GH¢                               Ghana Cedis 
GHS                                   Ghana Health Service 
GSS         Ghana Statistical Service 
H/A                                 Height-for-age z-scores 
HPLC                            High Performance Liquid Chromatography 
IOM                               Institute of Medicine 
IRB        Institutional Review Board  
IU                                 International Unit 
IVACG                        International Vitamin A Control Group 
JSS                               Junior Secondary School 
Kcal              Kilocalorie 
mg         Milligram 
ml              Millilitre 
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MOH                                 Ministry of Health 
NMIMR          Noguchi Memorial Institute for Medical Research  
P-value           Probability value 
RDA                                     Recommended Daily Allowance  
RDI                                  Recommended Dietary Intake 
RE          Retinol Equivalent 
RPO                                Red Palm Oil 
RI                                   Recommended Intake 
SD           Standard Deviation 
SSS                                  Senior Secondary School 
UNICEF          United Nations Children‘s Fund 
VAD                                Vitamin A deficiency 
W/A                                   Weight-for-age z-scores 
WHO                               World Health Organization 
 
 
 
  
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TABLE OF CONTENTS 
Content                Page 
DECLARATION ................................................................................................................... i 
DEDICATION ...................................................................................................................... ii 
ACKNOWLEDGEMENT ...................................................................................................iii 
ABSTRACT ......................................................................................................................... iv 
LIST OF ACRONYMS AND ABBREVIATIONS ............................................................. vi 
TABLE OF CONTENTS ...................................................................................................viii 
LIST OF TABLES ............................................................................................................... xi 
LIST OF FIGURES ............................................................................................................ xii 
 
CHAPTER ONE ................................................................................................................. 1 
1.0 INTRODUCTION .......................................................................................................... 1 
1.1 Background ..................................................................................................................... 1 
1.2 Problem statement ........................................................................................................... 3 
1.3 Objectives ........................................................................................................................ 4 
1.3.1 Main objective .............................................................................................................. 4 
1.3.2 Specific objectives ....................................................................................................... 4 
1.3.3 Study hypotheses .......................................................................................................... 5 
 
CHAPTER TWO ................................................................................................................ 6 
2.0 LITERATURE REVIEW ............................................................................................... 6 
2.1 Vitamin A physiology and importance ........................................................................... 6 
2.2 Dietary sources of vitamin A, pro- vitamin A and their bioavailability ....................... 11 
2.3 Factors affecting bioavailability .................................................................................... 13 
2.4 Vitamin A deficiency and its prevalence ...................................................................... 13 
2.5 Causes of VAD ............................................................................................................. 15 
2.6 Consequences of VAD .................................................................................................. 17 
2.7 Vitamin A deficiency control strategies ........................................................................ 18 
2.7.1 Vitamin A supplementation ....................................................................................... 18 
2.7.2 Food fortification ....................................................................................................... 21 
2.7.3 Dietary diversification ................................................................................................ 22 
2.8 Role of palm oil in nutrition and health ........................................................................ 23 
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2.9 Role of cowpea in nutrition and health ......................................................................... 25 
2.10 Anthropometric methods/measurements ..................................................................... 27 
2.10.1 Weight-for-age ......................................................................................................... 27 
2.10.2 Length/height-for-age .............................................................................................. 28 
2.10.3 BMI-for-age ............................................................................................................. 28 
2.10.4 Biochemical methods ............................................................................................... 28 
2.10.5 Dietary methods ....................................................................................................... 29 
2.10.5.1 24-hour recall ........................................................................................................ 30 
2.10.5.2 Food frequency questionnaire (FFQ) .................................................................... 30 
 
CHAPTER THREE .......................................................................................................... 32 
3.0 METHODOLOGY ........................................................................................................ 32 
3.1 Study design and setting ............................................................................................... 32 
3.2 Study participants, sampling and sample size ............................................................... 32 
3.3 Data collection .............................................................................................................. 33 
3.3.1 Background data......................................................................................................... 33 
3.3.2 Proximate analysis of intervention diet ...................................................................... 33 
3.3.3 Determination of total carotenoids content ................................................................ 33 
3.3.4 Determination of β-carotene content .......................................................................... 34 
3.3.5 Anthropometric measures .......................................................................................... 35 
3.3.5.1 Body weight ............................................................................................................ 35 
3.3.5.2 Height ...................................................................................................................... 35 
3.3.6 Dietary assessment ..................................................................................................... 36 
3.3.6.1 Food frequency questionnaire (FFQ) ...................................................................... 36 
3.3.6.2 The 24-hour diet recall ............................................................................................ 36 
3.3.7 Biochemical data ........................................................................................................ 36 
3.4 Baseline study ............................................................................................................... 37 
3.5 Intervention study.......................................................................................................... 37 
3.6 Data capture and analysis .............................................................................................. 38 
3.6.1 Anthropometric data................................................................................................... 39 
3.6.2 Food consumption data (nutrient intakes) .................................................................. 39 
3.7 Ethical consideration ..................................................................................................... 40 
3.8 Dissemination of findings of the study ......................................................................... 40 
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CHAPTER FOUR ............................................................................................................. 41 
4.0 RESULTS ..................................................................................................................... 41 
4.1 Socio-demographic characteristics of participants ....................................................... 41 
4.2 Availability and accessibility of vitamin A/carotenoid rich foods in the community .. 43 
4.3 Carotenoid content of the intervention diet ................................................................... 44 
4.4 Nutrient intake of participants ....................................................................................... 45 
4.5 Determinants of Vitamin A status among participants ................................................. 46 
4.6 Food consumption pattern among participants ............................................................. 47 
4.7 Serum retinol level of the participants .......................................................................... 48 
4.8 Effect of vitamin A on the occurrence of infection among the participants ................. 52 
4.9 Nutritional status of the participants ............................................................................. 53 
 
CHAPTER FIVE ............................................................................................................... 55 
5.0 DISCUSSION ............................................................................................................... 55 
5.1 Vitamin A nutrition and background characteristics of participants ............................ 55 
5.2 Dietary intake and nutritional status of participants ..................................................... 58 
5.3 Vitamin A status and infection rates among the participants ........................................ 61 
5.4 Implications of the study for nutrition and health ......................................................... 63 
5.5 Limitations of the study ................................................................................................ 64 
 
CHAPTER SIX ................................................................................................................. 66 
6.0 CONCLUSIONS AND RECOMMENDATIONS ....................................................... 66 
6.1 Conclusion .................................................................................................................... 66 
6.2 Recommendations ......................................................................................................... 67 
 
REFERENCES .................................................................................................................... 68 
 
APPENDICES .................................................................................................................... 86 
APPENDIX I: QUESTIONNAIRE .................................................................................... 86 
APPENDIX II: CONSENT FORM .................................................................................... 93 
APPENDIX III: SURVEY CHECKLIST ........................................................................... 95 
APPENDIX IV: MAP OF STUDY AREA ......................................................................... 96 
 
 
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LIST OF TABLES 
Table 1: Socio-demographic characteristics of participants (N=142)................................. 42 
Table 2: Proximate composition, caratenoid and vitamin A content of the intervention diet
 ............................................................................................................................................. 44 
Table 3: Energy contribution of macronutrients of the intervention diet relative to 
recommended intakes .......................................................................................................... 45 
Table 4: Nutrient intakes among participants pre-intervention and intervention relative to 
recommended intakes .......................................................................................................... 46 
Table 5: Predictors of Vitamin A status among the participants ........................................ 47 
Table 6: Weekly food consumption frequency of participants ........................................... 48 
Table 7: Serum retinol levels of participants pre and post interventions ............................ 49 
Table 8: Association between serum retinol and socio-demographic characteristics of 
participants .......................................................................................................................... 49 
Table 9: Association between serum retinol and nutritional status indicators .................... 51 
Table 10: Malaria parasite density of participants‘ pre and post interventions‘ ................. 52 
Table 11: Malaria status of participants‘ pre and post interventions .................................. 52 
Table 12: Nutritional status of participants‘ pre and post interventions ............................. 53 
  
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LIST OF FIGURES 
Figure 1: Interrelationship between retinol, retinal, and retinoic acid .................................. 7 
Figure 2: Schematic diagram of vitamin A metabolism ....................................................... 8 
Figure 3: Prevalence of vitamin A deficiency among participants ..................................... 50 
Figure 4: Prevalence of VAD among participants according to gender ............................. 51 
Figure 5: Nutritional status of participants‘ pre and post interventions .............................. 54 
 
 
 
 
 
 
 
 
 
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CHAPTER ONE    
1.0 INTRODUCTION 
1.1 Background 
Micronutrient malnutrition, hidden hunger remains a key public health challenge for 
individuals, households, governments, non-governmental organisations and the 
international community (Jones et al., 2005). Paramount among these micronutrient 
challenges is Vitamin A deficiency (VAD). VAD is particularly endemic among children 
in low income countries, especially in sub-Saharan Africa (Arlappa et al., 2008). Globally, 
WHO (1995) estimated that 28 million children under age five years had clinical VAD 
whereas 251 million children suffered from sub clinical VAD. Subsequently, Mason et al. 
(2001) appraised the situation and reported that 3.3 million children had clinical VAD and 
75-140 million children suffered sub-clinical VAD. Despite the differences in these 
estimates which may be attributable to the lack of reliable and representative data, VAD 
remains a major challenge worldwide. Africa is the second largest host of these children 
after Southeast Asia with nearly 50% of children affected.  In 1993, the Ghana Vitamin A 
Supplementation Trial Team reported a 65 % of severe vitamin A deficiency in children in 
northern Ghana. In 1997, the Ministry of Health Vitamin A prevalence survey revealed 
that 37.2% of children in southern Ghana had low serum levels of vitamin A. 
Subsequently, a cross-sectional study conducted among school children 2 – 10 years in 
Okwenya community of the Eastern Region of Ghana (Egbi, 2012) indicated that 36% of 
them were vitamin A deficient (serum retinol concentration < 20 ug/dL).  
 
Inadequate food intake (yellow flesh potato, mangoes, green leafy vegetables, liver, and 
milk), poor dietary quality, poor bioavailability (due to the presence of inhibitors and 
mode of preparation) and infection are among the major contributors to VAD 
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(Ramakrishnan, 2002). The vital role vitamin A plays in proper immune function makes 
its deficiency deleterious. Severe vitamin A deficiency can result in xeropthalmia, cornea 
ulceration, and permanent blindness. Some studies have associated night blindness and 
xerophthalmia with infrequent consumption of foods containing vitamin A (Mele et al., 
1991; Hussain et al., 1993 and Shanker et al., 1998). Vitamin A deficiency can also 
increase the severity of infections such as measles and diarrhoea and increase the risk of 
mortality (GSS, 2008).  
 
In view of the devastating consequences of VAD, several interventions tailored at redress 
have been proposed.  These include: 1) high-dose vitamin A capsule supplementation, 2) 
food fortification, and 3) food diversification and nutrition education.  Research suggests 
that high-dose vitamin A capsule supplementation to vulnerable young children is the 
most cost-effective short term intervention. However, food-based strategies have been 
identified globally as more viable and sustainable alternatives for addressing micronutrient 
deficiencies in populations (Benadé, 2003). In spite of this, many international VAD 
interventions have been more focused on supplementation.  
 
In Ghana, attention has been focused on vitamin A supplementation of infants and young 
children using immunisation as a key contact point. Industrial fortification, mainly 
voluntary is also another area that is being encouraged. Although dietary diversification is 
mentioned in the Ghana VAD control strategy (West Africa Conference on Vitamin A 
Deficiency, 1993), it is not being accorded the deserved attention. Dietary diversification 
strategies have mainly focused on nutrition education and behaviour change 
communication. In some instances, nutrition education may emphasise vitamin A rich 
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foods that are expensive and unaffordable by low income households who rely exclusively 
on staple crops like cereals, roots and legumes for their energy and nutrient needs.  
 
There is therefore a paucity of knowledge on the potential efficacy and effectiveness of 
food-based approaches that rely on plant sources to improve vitamin A status. Hence, 
there is need for evidence-based research to generate the required information to improve 
the content of health education messages for enhanced public health practice.  
 
Cowpea, a legume rich in energy, protein, iron and other nutrients, for instance is 
extensively consumed in West Africa. Cowpea-based foods are widely consumed in 
Ghana and hence constitute a major source of protein in the diet. Red Palm Oil (RPO) is 
carotenoid rich food which can be utilized as a fortificant in cowpea based diets to 
improve the vitamin A status and nutritional status of children. In spite of its availability 
throughout the year, children rarely consume RPO, and less than 40% of households 
adequately consume RPO (Amoaful, 2001). Providing at least one meal a day made from 
cowpeas and red palm oil may be a long term strategy to improving the nutrition situation 
of children. It is against this backdrop that the current study sought to test the use of 
cowpea and palm oil in improving the vitamin A status as well as the nutritional status of 
children in Kodzobi in the Volta Region of Ghana.  
 
1.2 Problem statement 
The very serious functional consequences of VAD among children continue to attract 
public health concern worldwide. In Ghana, it is estimated that VAD affects 26% of the 
country's under five population. Analysis using the PROFILES computer software show 
that VAD accounts for 1 out of 6 of all child deaths between the ages of 6 and 59 months. 
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Between 1997 and 2001 alone the number of child deaths due to VAD was estimated to be 
49,000. Elimination of VAD by the year 2001 could save the country substantial amounts. 
For instance, families could save about 11 million US dollars in terms of the care of sick 
children whilst savings to the nation would be about 58 million US dollars (Academy for 
Educational Development, 2003).  
 
Evidence from the GSS (2008) indicate that 57% of children under five in the study 
region-Volta Region of Ghana received vitamin A supplements 6 months prior to the 
survey. There is however a dearth of literature on the efficacy/effectiveness of plant-based 
food strategies in curtailing the VAD menace. Furthermore, notwithstanding the fact that 
VAD in children have strong ties with poor dietary practices the necessary steps are rarely 
made to reverse the situation. It is therefore important to assess the extent to which food-
based strategies can help to improve the vitamin A and nutritional status of children. 
 
1.3 Objectives 
1.3.1 Main objective 
To determine the serum vitamin A and nutritional status of children fed gari and beans 
stew. 
1.3.2 Specific objectives 
1. To identify the availability and accessibility of vitamin A/carotenoid rich foods in 
the community.  
2. To determine the carotenoid content of the intervention diet.  
3. To evaluate the dietary carotenoid intake of the children pre and post intervention 
in relation to RDI. 
4. To determine the serum retinol level of the children pre and post intervention. 
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5. To quantify the effect of vitamin A on the occurrence of infection among the 
children. 
6. To assess the nutritional status of the school children pre and post intervention.  
1.3.3 Study hypotheses 
1. The consumption of cowpea-based foods will improve the nutritional status of the 
children. 
2. The consumption of RPO will improve the vitamin A status of the children. 
 
 
 
 
  
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CHAPTER TWO 
 
2.0 LITERATURE REVIEW 
Globally, undernutrition is one of the principal issues of public health significance that 
continues to engage the attention of the international community. Micronutrient 
undernutrition or hidden hunger is particularly of greater concern as its deleterious effects 
pervade the biological, physical, socioeconomic and cultural aspects of humanity (WHO, 
2000; and UNICEF, 2012). Vitamin A is of huge relevance to human existence as this is 
palpable through the consequences of its deficiency (Kapil and Bhavna, 2002).  
 
Several interventions have been implemented over the years towards the mitigation of 
vitamin A deficiency. The universal standard interventions for vitamin A deficiency 
(VAD) control include; supplementation, fortification and dietary diversification (Butt et 
al., 2007). It is the latter of these interventions that is the theme of this thesis. The review 
is therefore focused on the existing knowledge and gaps on vitamin A, and its deficiency 
control with emphasis on food based approaches in relation to vulnerable Ghanaian 
children fed gari and beans stew. 
2.1 Vitamin A physiology and importance 
Vitamin A comprises retinoids and precursor varieties, provitamin A or carotenoids. 
Retinoids (retinol, retinal, and retinoic acid) are the biological functional forms of vitamin 
A. The interrelationship between these forms of vitamin A is shown diagrammatically in 
figure 1. 
 
 
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(Nelson and Cox, 2005) 
Figure 1: Interrelationship between retinol, retinal, and retinoic acid 
 
Retinol, the most reduced form of the vitamin, satisfies the requirements for all known 
functions of vitamin A. Although, retinol is not the active form for all the metabolic 
processes in the body that require vitamin A; it can be converted to retinal and retinoic 
acid, other active forms of the vitamin A family (Bowman and Russell, 2001). Vitamin A 
is present in food as retinol esters. Upon food consumption, there is hydrolysis of retinol 
esters in the intestinal mucosa, yielding retinol and free fatty acids. Retinol yielded from 
either esters or carotenes must undergo re-esterification to long chain fatty acids in the 
mucosal lining of the intestines. It is then secreted as a constituent of chylomicrons into 
the lymphatic system where its absorption and storage takes place in the liver (Awan, 
2005). Figure 2 shows a schematic diagram of vitamin A metabolism. 
 
 
 
 
 
 
Retinoic acid Retinal Retinol 
 
 
 
Rhodopsin 
Retinyl 
esters 
(storage) 
 
Excretion 
products 
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(Shils et al., 2006) 
Figure 2: Schematic diagram of vitamin A metabolism 
 
DIETARY 
SOURCE 
      RETINOL RETINYL PALMITATE BETA-CAROTENE 
RETINOL 
(RETINOL + ESTER) 
Emulsification and absorption  
Re-esterification with palmitic acid
  
Other target cells Photoreceptors Epithelial cells Periphery 
(Utilization) 
Dioxygenase 
(intestinal mucosa) 
RETINAL 
Hydrolase 
(pancreatic juice) 
Intestine  
(Metabolism 
& Absorption) 
Liver 
(Storage) 
RETINOL 
TRANSTHYRETIN 
RBP 
RETINOL 
RBP 
Blood 
(Transport) 
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During periods of low serum retinol levels, retinol is released from the liver into the blood 
by retinol-binding protein (RBP). In the blood, the retinol-RBP then binds to a bulkier 
protein, transthyretin. The transthyretin-RBP-retinol compound then circulates in the 
blood, distributing retinol to the tissues; while resisting renal excretion as a result of its 
large size (Blomhoff et al., 1991). The uptake of the retinol-RBP compound by the cells of 
peripheral tissues is facilitated by specific receptors on the surfaces of the cells. Cellular 
RBP facilitates the transport of retinol to the nucleus where it performs functions similar 
to those of steroid hormones (Ong, 1994).  
 
Inadequate dietary intake of protein, energy and some micronutrients such as zinc can 
militate against the hepatic synthesis of certain proteins that are crucial to the mobilization 
and transport of vitamin A. Zinc for example is required for the synthesis of RBP (Mann 
and Truswell, 2000). As a result, zinc deficiency decreases the amount of serum retinol in 
circulation which causes a functional deficit in vitamin A even when hepatic stores are 
adequate (WHO, 2011). Respiratory infections (Stephensen et al., 1994), diarrhoea and 
abnormal kidney performance (Alvarez et al., 1995) are among the factors that can result 
in vitamin A loss via urine. Fortunately, retinol-RBP can re-extract retinol in urine thereby 
resulting in its conservation (Champe et al., 2005; and Green and Green, 1994). This 
process ensures the prevention of urinary losses of vitamin A. As such vitamin A status 
cannot be assessed using urine (Green and Green, 1994).   
 
The role of vitamin A as a constituent of rhodopsin which is the visual pigment in the rod 
cells of the retina required for vision has long been established (Arlappa et al., 2008). 
Other functions of vitamin A include; its critical role in cellular differentiation and 
proliferation, growth, reproduction, proper performance of epithelium mucosa, and it is an 
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integral part of immunity (Stephensen, 2001). Specifically, the oxidized form of retinol, 
retinoic acid is regarded very relevant in the differentiation of white blood cells (Gaines 
and Berliner, 2003). The vitamin is particularly required for proper brain, kidney and liver 
development during the early stages of life (Ghoshal et al., 2003). During childhood, 
vitamin A facilitates tooth and bone development (Butt et al., 2007). When dietary 
consumption of vitamin A is sufficient, the risk of the occurrence of cardiovascular 
diseases and cancer among others is minimal (Weber, 1994; and Verma, 2003). In an in 
vitro study, Hamzah et al. (2003) demonstrated that vitamin A inhibits the proliferation of 
Plasmodium falciparum, the bacterium that causes malaria. This suggests that the vitamin 
may be protective against malaria.  
 
Studies show that vitamin A and protein nutriture are directly related. Children who are 
protein-energy deficient have been reported to exhibit low concentrations of total proteins, 
albumin and retinol-binding proteins (Burri et al., 1990 and FAO/WHO, 2001). VAD may 
also compromise immune function in humans. This is because goblet cell numbers 
decrease in epithelial tissues during VAD. As a result, mucous secretions which contain 
antimicrobial components also diminish. This situation leads to a failure of the 
regeneration and differentiation of cells lining the surfaces of protective tissue resulting in 
the flattening and keratinizing of these surface cells. These factors, that is: the decline in 
mucous secretions and the loss of cellular integrity weaken resistance to invading 
pathogenic organisms (Ross and Stephensen, 1996; and Stephensen, 2001). In an earlier 
study, Vobecky et al. (1986) found low concentrations of immunoglobulin IgG and IgM in 
children with low vitamin A consumption.  
 
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In view of the physiological roles of vitamin A, it is necessary for the levels of the vitamin 
to be kept at normal levels in the body. The normal serum status of vitamin A is 30 to 95 
g/dL although this may be a bit lower in children. Serum levels of carotene and retinol 
esters are usually 50 to 200 g/dL and 3–5 μg/dL respectively (David et al., 1996). In order 
to maintain these values, it has been suggested that a 700 RE Recommended Daily 
Allowance (RDA) for adults and for 1 to 13 year-old children the RDA is 300 to 600 RE 
or 60.00 IU/Kg of body weight (Trumbo et al., 2001). Attempts to meet the RDA figures 
for vitamin A must be carefully done since toxicity can result from overdose of vitamin A. 
For example, when children consume up to 330,000 IU of vitamin A, toxicity will result. 
In adults, the intake of 660,000 IU of vitamin A can lead to toxic effects such as dry, 
rough skin, hepatomegaly, joint pains, growth retardation, and hemorrhage. However, it 
has long been pointed out that no amount of carotenoids intake can result in toxicity since 
the bioconversion of these precursor forms is inversely proportional  to a person‘s vitamin 
A status (Wang et al., 1991). 
2.2 Dietary sources of vitamin A, pro- vitamin A and their bioavailability 
The dietary sources of vitamin A are primarily retinoids from animal tissue and carotenoid 
from plants. Retinol is the form of vitamin A that satisfies all known functions of the 
vitamin. Retinol, mainly found in foods of animal origin is readily used by the human 
body. The foods that are abundant in vitamin A (retinol) include; fish oils, liver, other 
organ meats, full-cream milk, and butter. Fortified foods such as fortified cereals and 
margarine also provide vitamin A (Guthrie and Picciano, 1995; and Trumbo et al., 2001). 
On the other hand, pro-vitamin A carotenoids are found in plant diets and they are 
convertible to vitamin A. The major contributors of provitamin A carotenoids are leafy 
vegetables, palm fruits, yellow fruits, carrots, cantaloupes, sweet potatoes, and spinach 
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(Harrison, 2005).  Red palm oil (RPO) has a high content of carotenoids and is one of the 
abundant sources of β-carotene. Manorama and Rukmini (1991) revealed that RPO 
contains approximately 550 µg/g of total carotenes and 375 µg/g of β-carotene. A 
reasonable part of vitamin A is provided by provitamin A carotenoids (Trumbo et al., 
2001). Common carotenoids found in foods are β-carotene, α-carotene, lutein, zeaxanthin, 
lycopene, and cryptoxanthin (de Pee and West, 1996). Of the 563 identified carotenoids, 
less than 10% are precursors for vitamin A (Bendich and Olson, 1989). Among these, β-
carotene is the most efficiently converted to retinol. Αlpha-carotene and β-cryptoxanthin 
are also converted to vitamin A, but only half as efficiently as β-carotene. Lycopene, 
lutein, and zeaxanthin are carotenoids that do not have vitamin A activity but have other 
health promoting properties (Olson and Kobayashi, 1992; Olson, 1996; and Paiva and 
Russell, 1999). These carotenoids have been shown to function as antioxidants in 
laboratory tests. Antioxidants protect cells from free radicals, which are potentially 
damaging by-products of oxygen metabolism and may contribute to the development of 
some chronic diseases (Butt et al., 2007).  
 
Animal sources of vitamin A are well absorbed and used efficiently by the body. Plant 
sources of vitamin A are not as well absorbed as are animal sources (Olson, 1996; and 
Futoryan and Gilchrest, 1994). In developed nations, animal source foods (dairy products, 
eggs, liver) and fortified foods are the leading sources of vitamin A (West, 2000). 
However, plant sources; fruits, roots, tubers and leafy vegetables are the main contributors 
of provitamin A (carotenoids); representing more than 80% of total food intake of vitamin 
A in sub-Saharan Africa and this is because of their low-cost, high availability and 
diversity (Codjia, 2001). Although widely consumed by poor populations, plant 
provitamin A activity has been proven to be less (12μg of β-carotene for 1μg of retinol), 
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(Institute of Medicine, 2001) than previously assumed (6μg of β-carotene for 1μg of 
retinol) (FAO/WHO, 1976). These findings may partially account for the reason why 
VAD still persists in low income countries such as Ghana. 
2.3 Factors affecting bioavailability 
Vitamin A is a fat-soluble vitamin and as such it must be incorporated into micelles in a 
bile dependent reaction before it can be absorbed (Butt et al., 2007). The addition of oils 
or other fats to carrots, greens or other carotenoid-rich foods during cooking will therefore 
optimize the absorption of vitamin A. Accordingly, low (<15% of total energy) fat 
consumption reduces the absorption of carotenoids and vitamin A (Vijayaraghavan et al., 
1997). About 70 to 90% of Vitamin A is retained after food preparation across varying 
temperatures. For example, the results of a study by Manorama and Rukmini (1991) in 
India found that cooking losses of β-carotene were between 22 to 30% in most meals 
prepared with RPO.  This stability of vitamin A and carotenoids to high temperature is 
beneficial for their bioavailability. In 2007, Butt et al suggested that the bioavailability of 
β-carotene and other carotenoids increases several-fold during cooking because heat 
releases these substances from proteins to which they are bound in foods.   
2.4 Vitamin A deficiency and its prevalence 
The total body stores of vitamin A range from 300 to 900 mg, 80% being in the liver and 
20% in peripheral organs and tissues. In normal individuals, the liver concentration of 
vitamin A should be 450 mg (Leo and Lieber, 1999). According to the WHO (2011) VAD 
assumes severe public health significance requiring intervention when ≥ 20% of a 
population exhibits serum retinol concentration ≤ 20 µg/dL. A well-nourished child will 
usually have adequate liver stores of vitamin A to maintain serum retinol levels of 10 to 14 
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µmol/1itre (WHO, 1995). Therefore, in values below these, normal levels of serum retinol 
may be difficult to attain or certain roles may be impaired (WHO, 1995).  
 
VAD methodological estimates date back to the 1960s. Using clinical records, anecdotal 
observations and personal interviews; 20,000 to 100,000 children were projected to be 
affected worldwide (Underwood, 2004). Subsequent estimates, recorded that 13 million 
children globally were xerophthalmic (Underwood, 2004). In 2000, the Administrative 
Committee on Coordination—Subcommittee on Nutrition (ACC/SCN) estimated that 
140–250 million preschool age children were at risk of vitamin A deficiency disorders 
(VADD, clinically deficient and subclinically vulnerable), including 3 million who have 
clinical signs every year. According to West (2002), 127.2 million preschoolers were 
vitamin A–deficient worldwide. Of this number, 25% of them live mostly in developing 
countries. Additionally, 26% of these vitamin A–deficient children are hosted by Africa, 
with the largest number in Ethiopia (6.7million). In more recent global population-based 
surveys WHO (2009) puts VAD among preschool children at 190 million. Considering 
these statistics on the burden of VAD, Africa comes second to South-east Asia. However, 
VAD is almost non-existent in the developed world. 
 
Maziya-Dixon et al. (2006) reported that in neighbouring Nigeria, 33% of children under 
five years are affected by VAD. In Ghana, the vitamin A supplementation trial in 1993 
(VAST, 1993) reported 65 % severe vitamin A deficiency in children in the northern part 
of the country. In 1997, four years later, the Ministry of Health Vitamin A prevalence 
survey revealed that 37.2% of children in southern Ghana had low serum levels of vitamin 
A. Subsequently, a cross-sectional study conducted among school children 2 to 10 years in 
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Okwenya community of the Eastern Region of Ghana (Egbi, 2012) indicated that 36% of 
them were vitamin A deficient.  
2.5 Causes of VAD 
Having underscored the global significance of the VAD menace, it is relevant to identify 
some of the contributory factors to this preventable condition especially among women 
and children. Generally, the occurrence of VAD is dependent on age, sex and season 
(WHO, 1995). Miller et al. (2002) noted that children suffer VAD as a result of inadequate 
secretion of the nutrient in breast milk; low consumption of vitamin A-rich foods, and 
infection. As have been categorized in other previous sections, the causes of VAD will be 
viewed bearing in mind the situation in developed countries on the one hand; and 
developing countries on the other hand. 
 
Mothers in low income countries have low vitamin A concentration in their breast milk 
because they consume diets low in vitamin A. For example, the National Health and 
Nutrition Examination Survey (NHANES III, 2000) results revealed that women in high 
income countries such as the United States meet 75–90% of the recommended Daily 
Allowance (RDA) whereas their counterparts in low income economies like Bangladesh 
meet only 31 to 57% of RDA (Zeitlin et al., 1992). 
 
Low consumption of vitamin A-rich foods has been identified as another cause of VAD in 
childhood. For instance West et al. (2002) stated that children in developed economies 
obtain most of their vitamin A from animal foods, while underprivileged children in 
developing nations eat most of their vitamin A from affordable plant sources which may 
have  low vitamin A activity. For example, among 1 to 3-year-old children, the median 
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consumption of vitamin A from animal sources NHANES III (2000) was 404 µg, which 
exceeded their RDA of 300 µg by as much as 35%. However studies of preschool children 
in some developing countries; India (Ramakrishnan et al., 1999), Kenya, Mexico, and 
Egypt (Calloway et al., 1993) revealed that intakes of animal sources of vitamin A were 
33, 50, 119, and 174 µg respectively, supplying only 11 to 58% of the RDA. In a similar 
study in Bangladeshi children, the only source of preformed vitamin A consumed was 
breast milk with children hardly obtaining vitamin A from animal sources (Zeitlin et al., 
1992). These low intakes of preformed vitamin A coupled with the low bioavailability of 
provitamin A carotenoids help explain why children in developing countries continue to 
suffer from VAD. 
 
A third major contributor to VAD among children in developing countries is infection. For 
example diarrhoea and helminthes infestation undermine the integrity, morphology and the 
performance of the intestinal absorptive mucosa all of which may result in malabsorption 
of vitamin A (Stephensen, 2001). Several studies have estimated that the prevalence of 
diarrhoea among children in developing countries vary from 10 to 19% (Molbak et al., 
1994; and McLaren and Frigg, 2001). Consequently, the average child in a developing 
country may suffer diarrhoea about 36 to 70 days annually. According to Black et al., 
(1982) the prevalence of acute respiratory illness suffered by children in developing 
countries is staggering, 25 to 60%. Illness aggravates vitamin A status mainly by 
decreasing the quantity of food consumed due to anorexia and malabsorption and 
increasing food utilization through higher catabolism and urinary loss. Anorexia is a 
leading contributor to low dietary consumption during periods of diarrhoea among 
children, a situation under which dietary intake is best studied (Bentley et al., 1991).  
Reduction in food intake appears to be more profound among weaned children suffering 
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from diarrhoea compared to children still breastfeeding. For instance, diarrhoea resulted in 
20% reduction in energy intake among weaned Guatemalan children not receiving breast 
milk (Martorell et al., 1980).  
Beyond reductions in food intake due to diarrhoea, malabsorption of vitamin A may arise 
during diarrhoeal disease and lower respiratory infection. Sivakumar and Reddy (1972) 
demonstrated virtually complete absorption of oily retinol by healthy children whereas 
there was a 30% decrease in the absorption of the same oily retinol among children with 
respiratory infection and gastroenteritis. In a related study, the absorption of a 100,000 IU 
of supplemental vitamin A was reduced by 22 and 17% when added to oral rehydration 
salt solution and water, respectively in diarrhoeal children (Reddy et al., 1986). Apart 
from malabsorption, higher catabolism of vitamin A during infection may as yet be 
another factor leading to VAD. In a study by Beisel (1972), it was revealed that higher 
catabolism is a consequence of the acute-phase response to infection, such as fever and 
metabolic degradation of muscle and adipose tissue. In healthy adults fed an adequate diet 
free of vitamin A, there was a 0.5% of total body lost of vitamin A per day (Sauberlich et 
al., 1974). 
2.6 Consequences of VAD 
This section is focused on the adverse effects that VAD has on the overall health and well- 
being of the human body. VAD negatively impacts many physiological systems in the 
human body in several ways. In VAD, normal mucus secreting epithelium is replaced by 
keratinized epithelium resulting in a decline in cellular immunity (Butt et al., 2007).  
There is evidence to suggest a relationship between low serum retinol and birth weight. 
Gazala et al. (2003) found that lower serum retinol concentration in cord and maternal 
serum at delivery from healthy mothers and healthy mature newborns related positively to 
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lower birth weight. VAD also contributes to growth retardation (Mwanri et al., 2000). It is 
well established that VAD results in xerophthalmia, night blindness, damages respiratory, 
genitourinary and gastrointestinal tracts, impairs growth and bone formation and leads to 
anaemia as well as increased susceptibility to infections (Sommer, 1989). Prolonged VAD 
leads to corneal ulceration and eventually partial or total blindness (keratomalacia). VAD 
appears to influence morbidity patterns especially in developing countries. For example, 
there is a two-fold and a three-fold risk of ARIs and diarrhoea respectively for children 
with mild vitamin A deficiency. Such children have a six to nine times higher risk of 
dying. Furthermore, when intervention is non-existent during VAD (keratomalacia), the 
mortality rate is as high as 60% (WHO, 1995).  
2.7 Vitamin A deficiency control strategies 
In view of the undesirable consequences of vitamin A which are largely preventable, the 
control of its deficiency has been a major subject of scientific exploration for the last two 
decades. Three strategies: vitamin A supplementation, fortification and dietary 
diversification are generally recognized as pillars in the combat of VAD (Bloem et al., 
1998; Filteau and Tomkins, 1999; and Chakarvarty, 2000). Of these three strategies, 
dietary diversification has been observed to be the most effective and sustainable approach 
in dealing with VAD. Each of these strategies will be examined in the remaining part of 
this section of the review. 
2.7.1 Vitamin A supplementation 
One of the earliest scientific investigations with daily dose vitamin A supplements was 
conducted among measles patients in London in the 1930s and it demonstrated that 
supplementation could reduce measles case-fatality by 50% (Sommer, 2008). Some other 
randomized controlled trials found nearly the same result (Hussey and Klein, 1990; and 
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Sommer and West, 1995). By the early 1990s, there was global publicity by high level 
international organizations such as United Nations Children‘s Fund (UNICEF) and United 
States Agency for International Development (USAID) of the effectiveness of vitamin A 
supplementation on overall mortality especially from measles based on ample evidence. 
This publicity stimulated the institution of national programmes in more than 70 countries 
in which about 500,000 vitamin A supplements are distributed every year saving 350, 000 
deaths among children (Sommer, 2008).  
 
 High dose vitamin A supplementation is recognized as the quickest response to improve 
the vitamin A status in deficient population among vulnerable groups (children, refugees, 
women, elderly) (Food and Agriculture Organization, FAO, 1992). High dose vitamin A 
supplementation programmes adopt three ways of reaching affected populations:  
Xerophthalmia Treatment, Universal Distribution, and Targeted Distribution to vulnerable 
children (WHO, 1997). Most countries including Ghana, have adopted 
WHO/UNICEF/IVACG (1997) recommendations for the operations of their vitamin A 
supplementation programmes. These recommendations stipulate that in VAD endemic 
communities, children  6 to 12 months should receive a 100,000 IU dose, while children ≥ 
12  and mothers should be given 200,000 IU of vitamin A once every 4 to 6 months.  
 
Albeit supplementation programmes have been appraised to be cost-effective and 
acceptable, they are not sustainable in the long term because they fail to tackle adequate 
dietary vitamin A intake to meet the body‘s physiological requirements. Vitamin A 
supplementation programmes are also coverage dependent and have challenges with 
compliance (Butt et al., 2007). In a recent commentary published at the launch of the 
World Public Health Nutrition Association Journal, Latham (2010) also challenged with 
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several reasons the conventional practice of giving children massive doses of synthetic 
vitamin A.  
 
In contrast to the claim by the Beaton report et al.(1993) that vitamin A supplementation 
had a 23% reduction on overall mortality; some studies suggest adverse effects of vitamin 
A on morbidity. For example, a randomized placebo-controlled double masked trial in 
Indonesia among 1407 young children concluded that high dose vitamin A supplements 
amplified the incidence of Acute Respiratory Illnesses (ARI) by 8%, and Acute Lower 
Respiratory Illnesses (ALRI) by 39%. The study also found that adverse effects on acute 
lower respiratory illnesses were more profound among well-nourished children (Dibley et 
al., 1996). In a Meta-analysis of 9 randomised controlled trials Grotto et al. (2003) 
concluded that high medicinal doses of vitamin A increased the incidence of respiratory 
tract infections and it is not defensive against diarrhoea among children. Furthermore, 
there is no reliable data in the entirety of countries earmarked for vitamin A 
supplementation (UNICEF, 2005 and 2007). High dose vitamin A supplements have also 
been found to antagonize the action of vitamin D which results in bone fragility (Rohde et 
al., 1999; and Rohde and DeLuca, 2005). Another difficulty with the vitamin A capsule 
initiative is the economics associated with it. Estimates from Ghana, Nepal and Zambia 
showed that the annual cost for an average national vitamin A supplementation 
programme is a colossal $US 3 million (UNICEF, 2007), which would be a huge burden 
for many developing countries, as asserted by Latham (2010). In 2009, a conclusion was 
drawn by the Micronutrient Initiative to the effect that: ‗Supplementation remains largely 
a push-driven rather than a demand-driven intervention‘. 
  
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In the light of the above concerns, many scientists (Latham, 2010; and Gopalan et al., 
2010) have called for a paradigm shift which emphasizes food-based strategies in the 
solution to the VAD challenge. These critics of the vitamin A capsule programme 
however, concede that supplementation should only be used in VAD endemic areas.  
2.7.2 Food fortification 
Food fortification is the process of adding a desirable/essential nutrient to a commonly 
consumed food product in order to enhance the content of the nutrient in the food for the 
purposes of avoiding and/or controlling a deficiency in a population (FAO/WHO, 1994). 
This method has been part of the success story in the elimination of vitamin A deficiency 
in developed countries (Osei et al., 2010). There have been several studies to suggest that 
this method is a successful way of improving vitamin A status. Lotfi et al. (1996) showed 
that several foods have been vitamin A fortified to help in the elimination of VAD. 
Among these foods include; rice, wheat, sugar, tea, monosodium glutamate, fats and oils, 
and biscuits. In view of this, several countries are fortifying common food products with 
vitamin A (UNICEF, 1996). 
 
Fortified vegetable oil used in the preparation of a rice-based diet has been successful in 
significantly improving the concentration of plasma retinol and liver stores of vitamin A 
(Favaro, 1992). In a similar instance, consumption of 40 g of bread prepared from wheat 
flour fortified with 4.5 g/kg vitamin A has also been found to significantly result in higher 
liver stores of vitamin A among school children in the Philippines (Solon, 1997).  Vitamin 
A fortified monosodium glutamate has also been proven efficacious in the Philippines 
(Solon et al., 1985) and Indonesia (Muhilal et al., 1988). Van Stuijvenberg et al. (1999) 
studied 6 to 11-year-old rural children in KwaZulu-Natal, South Africa consuming biscuits 
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fortified with synthetic β-carotene and indicated that 50% of their RDA for retinol was 
provided. 
 
For food fortification to have the desired impact on vitamin A status it is important for 
fortification to be mandatory and centrally processed (Dary and Mora, 2002). This may be 
the limiting factor in the developing world. In Ghana, it is the fortification of salt with 
iodide that has been mandatory and even then there may be challenges with the 
enforcement of the law (Ghana News Agency, GNA, 2009). The high cost and slow 
progressive nature of fortified food products may also be another key challenge which 
limits food fortification as a strategy in curtailing VAD among poor populations (Shiundu 
et al., 2007). 
2.7.3 Dietary diversification 
Dietary diversification is the consumption of food from the various food groups in order to 
meet nutrient needs. In the case of vitamin A, this implies consuming animal source foods 
such as milk, dairy products, liver, eggs, poultry, fish and a variety of plant based foods 
which contain an abundance of carotenoids, β carotene (green leafy vegetables, carrots, 
mangoes, sweet potatoes, red palm oil). Although animal sources are richer in retinol 
compared to plants, they are often expensive and unaffordable in developing countries. On 
the contrary, plant source foods are locally available and as such are more affordable, 
acceptable and culturally appropriate and therefore easy to be incorporated in the diet of 
poor households (Latham, 2010; and Codjia, 2001). There are some studies that indicate 
that plant based diets are cost-effective in meeting the vitamin A and other nutrients of 
populations where attention is paid to their consumption.  
 
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In a three-year project, it was shown that frequent consumption of vegetables among under 
five year-olds resulted in an annual per capita cost of US $0.13 (Greiner and Mitra, 1999). 
Ncube et al. (2001) also indicated in a randomised trial that consumption of tropical fruits 
improved the serum retinol of women as effectively as dosing with β-carotene. Studies 
suggest that if 35 to 50% of the RDA of vitamin A is met by the consumption of RPO, it 
will be sufficient to prevent VAD (Benadé, 2003). In a pre-post test study design, RPO 
used in the preparation of school lunch meals was found to significantly improve the 
serum retinol concentration of school children in Burkina Faso (Zeba et al., 2006).  
 
A cross examination of the literature reviewed so far reveals that dietary diversification is 
the most appropriate strategy for combating VAD in the developing world including 
Ghana. 
2.8 Role of palm oil in nutrition and health 
Red Palm Oil (RPO) is a product of the oil palm fruit (Elaesis guineensis) that has been 
part of civilization for over 5000 years. Palm oil originated from Africa but in 
contemporary times it is widely consumed in other continents such as South-east Asia, and 
South America. In 2007, it was estimated that the world production of RPO had reach 40 
million metric tons of which Malaysia alone accounted for nearly 50% (Sarmidi et al., 
2009). Although, RPO originated from Africa; Asia has become the leading producer of 
RPO in the world. For instance, Malaysia and Indonesia alone account for 90% of palm oil 
export trade in the world (Rupilius and Ahmad, 2007). In Ghana, palm oil is the preferred 
cooking oil among rural households except in the three northern regions where shea butter 
is the oil of choice due to the inadequate availability and accessibility of red palm oil in 
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that part of the country (GSS, 2008). As a result, red palm oil is much more expensive in 
those regions due to the additional transportation and other handling costs. 
 
RPO has many components such as carotene (the dominant one being β-carotene), vitamin 
E, sterols, squalines, enzymes and phenolic compounds that have several nutritional and 
other applications in the food industry (Choo et al., 1996; Lau et al., 2008). The quantity 
of carotenes contained in RPO is nearly 15 times higher than that contained in an equal 
weight of carrots, and 44 times that found in leafy vegetables (Scrimshaw, 2000). This 
makes RPO the richest known source of provitamin A (α and β carotenes). RPO can 
therefore be appropriately harnessed to fight VAD which is wide spread throughout the 
developing world (Scrimshaw, 2000). According to the Malayasian Palm Oil Council 
(2006), the RDA (350 to 400 RE) for vitamin A can be provided for children by one 
teaspoon (6 grams) whereas two teaspoon (12 grams) will meet the adult RDA (800 RE)). 
Several interventions have shown that RPO improves serum concentrations of vitamin A. 
In a two month snack trial among school children 7 to 9 years, it was revealed that serum 
retinol was significantly improved. Further assessment of vitamin A using the Modified 
Relative Dose Response Test also showed a saturation of liver stores of retinol (Jozwiak 
and Jasnowska, 1985). Van Stuijvenberg et al. (2001) investigated the effect of β-carotene 
among 5 to 11-year-old children in KwaZulu-Natal, South Africa and it was shown that 
biscuits fortified with RPO met 30% of the RDA for the children. Apart from its vitamin A 
nutritive value, RPO also has other benefits for the human body especially in 
cardiovascular health. The antioxidants contained in RPO have cancer and 
hypercholesterolemic protective effects (Pearce et al., 1992; Tomeo et al., 1995; Slattery 
et al., 2000). In a recent study, Ong and Goh (2002) indicated that palm oil increases high-
density lipoprotein (HDL) cholesterol whereas it decreases blood cholesterol, low-density 
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lipoprotein (LDL) cholesterol, and triglycerides; the overall effect being improved 
cardiovascular health. It is also known that Co-enzyme Q, a component of palm oil is 
defensive against artherosclerosis and heart disease (Kontush et al., 1995). 
 
Despite the numerous health benefits of red palm oil, some concerns have been raised 
suggesting that red palm oil could be a risk factor in the development of cardiovascular 
diseases (CVDs) because of its saturated fatty acid (oleic, palmitic, linoleic acids among 
others) content which have been reported to be hypercholesterolemic (Mensink and Katan 
1990; and Lichtenstein et al., 1999). In a recent study among 15 adults in Boston in the 
United States of America, Vega-Lo´pez et al. (2006) found that intake of palm oil 
enriched diets resulted in high plasma concentrations of LDL cholesterol and 
apolipoprotein which are a risk factor for CVDs. 
 
 In spite of this limitation, red palm oil like all fats also provides energy (Fasina et al., 
2006) in addition to its other health benefits discussed earlier and as such red palm oil is a 
useful energy source and rich in pro-vitamin A, and relatively cheap; hence an excellent 
food resource which must be included in the diet of growing children, especially of 
developing countries. Accordingly, the advantages of red palm oil outweigh its 
disadvantages especially when consumed in moderation.  
2.9 Role of cowpea in nutrition and health 
 Cowpea (Vigna unguiculata L. Walp) is one of the most extensively consumed legumes in 
the developing world (Phillips et al., 2003). In the Indian subcontinent and Africa, it 
constitutes a major part of the diet of vegetarians (Salunkhe, 1982). Cowpea is a common 
household food item in Ghana, Nigeria and other West African countries. Cowpeas are a 
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drought and heat resistant crop that requires as little as 300 mm3 of rain to mature (Apata 
and Ologhobo, 1997). For cowpeas ability to tolerate drought conditions, they can be 
grown at least once in the two major climatic seasons (rainy and dry season) across the 
vegetation zones of Ghana. Some cowpea varieties found in Ghana are Bengpla, Ayiyi, 
Asontem and Soronko (Osei and Sefa-Dedeh, 1993). Chemical analysis done on cowpea 
varieties showed the following composition: protein 20.7-25.4%; fat 1.38-1.99%; crude 
fibre 1.06-3.98%; ash 2.82-3.55% (Osei and Sefa Dedeh, 1993; Preet and Punia, 2000). 
Tshovhote et al. (2003) reported a protein concentration of 253.5 to 264.3 g/kg in some 
varieties of cowpea. The amino acid profile of cowpeas shows they have low sulphur 
content but high in lysine (Coertze and Venter, 1996). Although, cowpea is high in lysine, 
the digestibility of the lysine in cowpea is low compared to that of methionine (Tshovhote 
et al., 2003). Overall, the nutrient content of cowpea is similar to soybeans and canola. 
Comparable to other legumes, cowpea contains non-digestible and anti-nutrient factors 
(Igbasan and Guenter, 1997) such as protease inhibitors, non-starch polysaccharides 
(NSP), pectins and phenolic compounds (Arora, 1995). These substances undermine the 
protein quality and nutrient digestibility of cowpea. Protease inhibitors particularly hinder 
the functionality of pancreatic enzymes like chymotrypsin and trypsin. 
 
In Ghana cowpea is processed into many traditional foods. Many households in Ghana 
consume at least one form of cowpea based-food. In the southern part of Ghana available 
cowpea based foods include; apapransa, borboe, akara, koose, red-red, cowpea stew, 
cowpea vegetable soup and waakye. In the northern part of the country can be found 
indigenous traditional cowpea based foods like tubani, nyombeka, gablee and koose. 
Cowpea flour is also used as condiment in preparing soups and stews in northern Ghana. 
Most often cowpea is eaten in combination with other food groups (cereals, roots, tubers 
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and vegetables). Cowpea based diets such as waakye, koose and red-red are served by 
restaurants and hotels in urban areas. Despite their wide range of use, cowpea requires a 
long time to soak or cook. The long processing duration therefore makes the use of 
cowpea in the diet too expensive (Tshovhote et al., 2003). In spite of some of the 
challenges associated with cowpea mentioned already, the current study still employed 
cowpea because of its availability, affordability, and cultural acceptability in the study 
setting. Another reason for the choice of cowpea is its cholesterol-lowering effects in 
humans (Frota et al., 2008). This ability of cowpea may offset any hypercholesterolimic 
effects that may be posed by the red palm oil in the intervention diet. 
2.10 Anthropometric methods/measurements 
Anthropometry is the measurement of the human body parts. This can be a relatively rapid 
way of describing the growth and nutritional status of a person or population (Gorstein et 
al., 1994). This method is particularly used to determine protein energy malnutrition in 
children, and overweight and obesity in all age categories. The measurements commonly 
taken are weight and height. Anthropometry is quite objective and the technology for its 
application is simple (Duggan, 2010). The anthropometric indicators commonly applicable 
to child growth monitoring and development from 5 to 19 years are weight-for-age, 
length/height-for-age, and BMI-for-age (WHO, 2009).  
 
2.10.1 Weight-for-age 
Weight-for-age measures underweight: weight for age < –2 standard deviations (SD) of 
the WHO Child Growth Standards median. Low weight for age (underweight) can be an 
indication for ‗wasting‘ (low weight-for-height), representing acute weight loss, ‗stunting‘, 
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or both. This makes weight-for-age a complex indicator and therefore presents 
interpretative challenges (WHO, 2009). 
2.10.2 Length/height-for-age 
This indicator measures stunting: length/height-for-age < –2 SD of the WHO Child 
Growth Standards median. Height-for-age reflects cumulative linear growth and it is 
usually influenced by long-term food shortages, chronic and frequent recurring illnesses, 
inadequate feeding practices, and poverty (WHO, 2009). 
2.10.3 BMI-for-age 
This replaces weight-for-age for children ten years and above. BMI-for-age is interpreted 
within -3 SD, -2 SD, -1 SD, +1 SD, +2 SD and +3 SD. The BMI values for children 5 to 
19 years are interpreted as those of adults in the WHO reference (overweight occurs at +1 
SD (BMI =25 kg/m2); the cut-off for obesity is +2 SD (BMI=30 (kg/m2), whereas morbid 
obesity occurs at the +3 SD (BMI of above 35 kg/m2). Thinness and severe thinness occur 
at the -2 and -3 SD cut-offs respectively (WHO, 2009). 
2.10.4 Biochemical methods 
Preformed vitamin A, retinol is the most abundant form of vitamin A in the blood. The 
vitamin is usually stored in the liver. When blood levels of vitamin A fall, liver stores of 
the vitamin are used to boost the circulating levels in order to meet the requirements of 
body tissues. The transport of retinol to body tissues is facilitated by its carrier protein, 
retinol-binding protein (Gibson, 2005). Retinol-binding protein forms a complex with 
transthyretin in the blood. Transthyretin is responsive to certain receptors on target cells 
thereby regulating critical roles in the body. Retinol levels in serum do not adequately 
correlate with liver stores of the vitamin unless a person‘s liver stores are exhausted (< 
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0.07 μmol/g liver) or too high (> 1.05 μmol/g liver) (Gibson, 2005). Within this range, 
retinol levels in blood are regulated through homeostasis and do not always reflect vitamin 
A intake or clinical signs of deficiency. As a result, serum retinol is not a good indicator 
for evaluating the vitamin A status of individuals and may not be responsive to 
intervention programmes. However, serum retinol levels and inflammation/infection can 
provide population specific data on vitamin A status and serve as the basis for public 
health intervention (WHO, 1996). In many instances, serum retinol values are measured in 
young children, and vulnerable groups (WHO, 1996). 
 
There are several ways of assessing serum retinol. Serum retinol can be measured by 
High-pressure Liquid Chromatography (HPLC), by fluorescence, or by ultraviolet (UV) 
spectrophotometry. In spite of its higher cost, HPLC is the appropriate and preferred 
method for serum retinol determination because of its relatively high sensitivity and 
specificity (WHO, 1996). Serum retinol can be determined in a venous or free-flowing 
capillary blood sample. Samples to be analysed should not be exposed to light and must be 
kept chilled prior to centrifugation. Analysis on samples should be carried out within a 12 
hour period of sample collection (WHO, 1996). Serum retinol may also be determined 
using dried blood spots (Gibson, 2005). 
2.10.5 Dietary methods 
There are different methods for collecting dietary intakes and the choice is influenced by 
time, cost and the purpose of the data. In addition to the mentioned factors, each method 
has its own pros and cons and all these together dictate the method.  In this study, time and 
cost were the greatest influence in the selection of the 24-hour recall and food frequency 
questionnaire. The food frequency questionnaire was used to buttress the 24 hour recall. 
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2.10.5.1 24-hour recall 
In the 24-hour recall method of dietary assessment, the participant answers a series of 
questions aimed at eliciting information on all the drinks and foods as well as their portion 
sizes that have been consumed the previous day. This method can be very flexible in that 
the tool can be self-administered, through face-to-face interview or via telephone (Buzzard 
et al., 1996; and Casey et al., 1999). Probing is very essential to the success of a 24-hour 
recall exercise and as such it requires interviewers to be properly trained in the 
administration of the tools. To ensure maximum success, dieticians, nutritionists or 
interviewers should have adequate knowledge on the food distribution as well as some of 
the food processing techniques within the study area. The 24-hour recall presents several 
advantages to the researcher. It does not require literacy on the part of participants since 
all the questions are asked in a language they understand and the recording of information 
is done by the interviewer. There is less burden placed on participants and recall bias is 
minimized since a 24-hour period is relatively short. It is also easier to get people to agree 
to participate in a study using a 24-hour recall than recruiting people to participate in a 
study employing food record (Thompson and Subar, 2001).  
2.10.5.2 Food frequency questionnaire (FFQ) 
This method requires study participants to provide information on foods they commonly 
consume from a list of usually consumed foods in their locality (Willett, 1998; and Zulkifli 
and Yu, 1992). Some FFQs also include questions on portion sizes for the purpose of 
approximating relative or absolute nutrient consumption. However, there is some 
disagreement as to whether or not the estimation of portion sizes should be included in the 
food frequency questionnaire. Whereas some advocate the inclusion of portion sizes in 
FFQs, others prefer the use of FFQs without the inclusion of portion sizes (Willett, 1998). 
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In a typical FFQ, the total nutrient consumption is obtained by the summation of all foods, 
the product of the frequency of each food item by the quantity of the nutrient in a 
particular serving of the food to yield an average nutrient intake, dietary components and 
food groups per day. Depending on the list of items included in a FFQ, the administration 
may be between 30 to 60 minutes. In such instances, participant burden should be 
considered. In spite of this concern some studies have revealed that participant burden is 
not critical in the use of FFQ (Subar et al., 2001; Eaker et al., 1998; Morris et al., 1998; 
and Johansson et al., 1997).  
 
  
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CHAPTER THREE 
3.0 METHODOLOGY  
3.1 Study design and setting 
The study was a 6 month one-group longitudinal pre - and - post - test design. The study 
was in 3 parts: 
 Part 1 was a survey to collect information on socio-demographics and vitamin A-rich 
foods in the community. 
Part 2 was an assessment of the chemical composition of the intervention diet. 
Part 3 was the intervention where data were collected at pre, and post intervention. 
 The study was conducted in Kodzobi in the Adaklu-Anyigbe district in the Volta Region. 
This district is one of the newly created districts that shares boundaries with the Ho 
Municipal Assembly, and the north and south Tong districts. The vegetation is mainly 
savanna with patches of forest. The inhabitants are mainly subsistence farmers engaged in 
cowpea, maize, groundnut and cassava cultivation. 
3.2 Study participants, sample size and sampling  
 
The study participants were school children (6 to 12 years) at Kodzobi Basic School 
(Primary-JHS). A sampling frame was constructed by pooling together the class registers 
from class 1 to Junior High School 3 (JHS). All children 6-12 years in the sampling frame 
qualified for the study.  A convenient sample of 142 children were selected after using 
simple random sampling where every third child was selected to participate in the study.  
The selection took place among children whose parents consented and the children also 
agreed to participate in the study. Prior to and during the study, all children who reported 
to be allergic to beans, palm oil or gari as well as those who were found to be using 
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vitamin and mineral supplements or any dietary supplements were excluded from the 
study.  
3.3 Data collection 
3.3.1 Background data 
A pretested semi-structured questionnaire made up of open and close ended questions was 
employed in the data collection. The instrument was in five parts (Appendix I): Part A 
elicited socio-demographic data on the participants, Part B retrieved information on 
participants‘ health/nutrition; Part C was used to assess the water and sanitation situation 
of participants; Part D assessed the cultural practices pertaining in the community; and 
Part E, a food frequency questionnaire which collected information on the frequency of 
food consumption especially vitamin A rich foods among the participants. 
3.3.2 Proximate analysis of intervention diet 
The nutritional composition of the intervention diet (gari and beans stew) was also 
analysed. Moisture content, energy, carbohydrate, crude protein, crude fat, and crude fibre 
were estimated by employing the standard method of analysis (AOAC, 1995).  
3.3.3 Determination of total carotenoids content 
Carotenoids were analyzed as described by Rundhaug et al. (1988) with slight 
modifications. Briefly, triplicates (0.7825g, 0.6185g and 0.6346g) of the diet was each 
transferred into a mortar and a small amount of anhydrous sodium sulphate added as a 
desiccant to allow for effective grinding and extraction with 50ml cold acetone. The 
mixture was filtered and the residue re-extracted under the same conditions until the 
extraction solvents became colourless. The filtrate was then partitioned on 20ml petroleum 
ether in a 500ml separating funnel. About 1L of distilled water was used to wash away the 
acetone by draining away the lower aqueous layer. The upper petroleum ether layer was 
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dried by passing it through anhydrous sodium sulphate sited on a cotton wool at the base 
of a funnel and the extract collected into a labeled centrifuging tube. The extract volume 
was recorded and then stored at -14oC to prevent oxidative damage until further analysis. 
Absorbance of the petroleum ether extract of the diet were measured at 450nm using a 
Shimadzu UV-120-02 spectrophotometer and total carotenoids content (expressed as β-
carotene equivalents) estimated using the equation below; 
 
Total carotenoids content (µg/g) = Absorbance × Total volume of extract (ml) × 104 
                                        Sample weight (g) × Absorbance coefficient of β-carotene (2592) 
 
Total carotenoids content (µg/100g) = Total carotenoids content (µg/g) × 100 
3.3.4 Determination of β-carotene content 
A standard β-carotene solution was prepared and the absorbance read on a Shimadzu UV-
120-02 spectrophotometer. Then, 20µl was injected into an HPLC and the areas were 
obtained. The concentration of the standards was calculated using the formula; 
Conc. of β-carotene standard (ng/µl)      =           Absorbance × 10000 
                         Coefficient of extinction of standard 
 
The mobile phase was n-hexane/benzene (6:1) at a flow rate of 0.8 ml/min and UV 
detection at 450 nm. Petroleum ether extract (400µl) of each triplicate stored was 
measured with a pipette into an eppendorf tube and evaporated to dryness under a steam of 
nitrogen gas. It was then reconstituted with a known volume (200µl) of the mobile phase 
and vortexed for thirty seconds. Subsequently, 20µl was injected into the HPLC and their 
corresponding areas obtained. Using the areas obtained, the concentration of β-carotene 
content of the sample was calculated using the following formulae: 
 
Conc. of β-carotene (ng/µl) in each extract = Area of each extract × Conc. of standard (ng/20µl) 
                                                                                             Area of standard 
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Conc. of β-carotene (ng/ml) in each extract = Conc. β-carotene (ng/µl) in extract × Recons. Vol 
                  Volume of extract injected into HPLC  
 
Conc. of β-carotene (ng/ml) in each extract = Conc. of β-carotene (ng/ml) in extract × Total Vol. 
 
 
Conc. of β-carotene (ng/g) = Conc. of β-carotene (ng/ml) in each extract 
     Sample weight (g) 
 
Conc. of β-carotene (µg/g) = Conc. of β-carotene (ng/g) × 0.001 
Conc. of β-carotene (µg/100g) = Conc. of β-carotene (ng/g) × 100 
 
3.3.5 Anthropometric measures 
3.3.5.1 Body weight 
The weights of the participants were measured using the electronic bathroom scale 
(Precision Health Scale UC-300). The weight measurement was taken in accordance with 
WHO (2006) protocol for anthropometry. The weight of each participant was taken three 
times and recorded to the nearest 0.1kg. The mean of the three readings was then taken as 
the actual weight of the participants. To ensure accuracy, weight measurements were done 
an hour prior to lunch with the participants wearing light clothing; the scale was also 
standardized using an object with a known weight. 
3.3.5.2 Height 
The height of the participants was taken with a stadiometer. Participants stood straight 
with the head in a position such that the Frankfurt plane was horizontal, feet together, 
knees straight and heels, buttocks and shoulder blades in contact with the vertical surface 
of the stadiometer. Furthermore, the arms were hanged loosely by the sides with the palms 
facing the thighs (WHO, 2006). Height measurements were also taken in triplicates and to 
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the nearest 0.1cm. The mean of the three readings was considered as the actual height of 
the participant. 
3.3.6 Dietary assessment 
3.3.6.1 Food frequency questionnaire (FFQ) 
The FFQ was used to assess the frequency of food consumption of participants with 
emphasis on cowpea-based foods and carotenoid-rich foods. Handy measures were used to 
help determine the quantities of cowpea-based foods and carotenoid-rich foods consumed. 
The information generated by the FFQ facilitated the determination of the frequency of 
consumption of the particular food and its implications on the vitamin A and nutritional 
status of the children.  
3.3.6.2 The 24-hour diet recall 
This was done for two week days and one weekend to help determine the 24-hour dietary 
intake of the participants. The 24-hour dietary recall consisted of a listing of foods and 
beverages consumed the previous day or the 24 hours prior to the recall interview. Foods 
and amounts were recalled from memory with the aid of interviewers who were trained in 
methods for soliciting dietary information. The interview was conducted face-to-face and 
whenever it was appropriate interviewers enquired from participants their activity history 
to facilitate probing for foods and beverages consumed. 
3.3.7 Biochemical data 
The present study concentrated on serum retinol to determine the vitamin A status of the 
participants. Blood (5 ml) was obtained from each participant by venipuncture by a well-
trained phlebotomist. The blood samples were then allowed to clot before centrifugation at 
2500rpm for ten minutes to obtain serum. The serum was labeled legibly and stored at -80 
oC and analysed within two weeks. For each subject, duplicate aliquots of serum were 
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analysed. Frozen serum samples were put into racks and covered with aluminum foil to 
prevent contact with light as retinol is very sensitive to light. Serum retinol was 
determined with the High Performance Liquid Chromatographic (HPLC) method 
(Noguchi Memorial Institute for Medical Research, NMIMR, 1997).  
3.4 Baseline study 
During the baseline study, the anthropometric measurements were conducted to assess the 
nutritional status of the children (6-12 years). Their dietary vitamin A intake from cowpea-
based foods and red palm oil (RPO) and other vitamin A rich foods were also assessed 
using a food frequency questionnaire. The vitamin A status of the children was assessed 
by determining their serum retinol concentration. Blood samples were collected by a 
phlebotomist under standard laboratory protocols. The participants were screened for some 
infections using self-reporting and laboratory techniques. The giemasa staining technique 
was used to screen the participants for malaria whereas the kato-catz technique was 
employed in screening participants for helminthes (hookworm) infestation. The 
participants who were found to have malaria were encouraged to go to the hospital for 
treatment whereas all the participants were dewormed with 400 mg of albendazole prior to 
the intervention. 
3.5 Intervention study 
During the intervention study, the participants (6-12 years) were fed 300g (246.5g beans, 
40g gari and 13.5g RPO) gari and beans stew prepared with RPO for lunch thrice a week 
for a period of six months. The rate of infection (malaria) during the intervention was also 
recorded in order to help to determine the frequency of infection among the participants. 
This was done in order to quantify the possible effect of vitamin A on infection among the 
participants. The diet was prepared under hygienic conditions to prevent contamination 
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and loss of nutrients. The participants were provided with feeding cups and spoons. They 
were also served clean drinking water during the meals. To prevent the participants from 
sharing their meals with their classmates, the feeding was closely supervised. The 
participants were apparently healthy and resident in the community throughout the study 
period. 
 
The research assistants were adequately trained to ensure appropriate data collection. All 
the tools for the data were pre-tested to ensure that the necessary corrections were made to 
aid in the collection of the appropriate data. To ensure efficiency and accuracy during the 
data collection, research assistants were trained and provided with a comprehensive 
protocol on the data collection procedure. 
3.6 Data capture and analysis 
The data were entered, cleaned and analysed using the Statistical Package for Social 
Sciences for Windows (version 16.0, SPSS Incorporated, Chicago, USA). Frequencies 
were used to describe background characteristics of participants that were categorical in 
nature. Nutrient contents of portion sizes were calculated using the Food Processor PLUS 
Nutrition and Fitness Software with Cooking and Preparation Yields (version 6.02, ESHA 
Research, USA). For dietary data obtained from food frequency, the frequency of 
consumption of the various food groups was calculated for each participant. Percent RDA 
met for each nutrient for both pre and post-test was reported as nutrient adequacy ratios. 
 
Weight-for-age (W/A), Height-for-age and BMI-for-age z-Scores were calculated for each 
participant. Means and standard deviations were calculated for continuous variables such 
as age, weight, height, and serum retinol that were reasonably normally distributed.  
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Differences in means of intervention variables such as retinol concentration, W/A, H/A 
and vitamin A status before and after the intervention period were determined using the 
paired t-test. 
Vitamin A status was categorised as a binary variable (deficient or normal) using serum 
retinol as indicator. Chi-squared test was used to examine the association between serum 
retinol and some categorical variables. Logistic regression models were used to explore 
the relationship between the main outcome variable (serum retinol) and background 
characteristics of study participants. Treating the main outcome of this study as a 
continuous variable, univariate and multivariate linear regression models were used to 
explore the relationship between serum retinol and socio-demographic characteristics of 
participants. All variables that were significantly associated with serum retinol from the 
univariate linear regression were adjusted for in the multivariate linear regression.  
3.6.1 Anthropometric data 
Anthropometric indices; weight-for-age and height-for-age, weight-for-height and BMI-
for-age were computed using the WHO anthroplus software, the latest growth standard 
proposed by the World Health Organization (WHO, 2007). The means and standard 
deviations of the z-scores for weight-for-age, height-for-age and BMI-for-age were 
determined.  
3.6.2 Food consumption data (nutrient intakes) 
The actual amount of foods consume by the children was estimated using representative 
food samples. The total amounts of the various nutrients: Protein, fat, carotene, and energy 
was calculated based on 100 grams portion of food with the help of Food Processor Plus 
Software (FPRO), a nutrient database and the Food Research Institute‘s food composition 
table.   
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The total amount of protein, fat, carotenoids, carbohydrate, and energy calculated was 
compared to the Recommended Dietary Allowances (RDAs). Nutrient Adequacy Ratio 
(NAR) was then calculated based on the information above as follows: 
 Actual nutrient in the diet  
       NAR (Nutrient Adequacy Ratio) =   
           Recommended Dietary Allowance for nutrient 
 
 
                                                                    
3.7 Ethical consideration 
Ethical approval was sought from the Institutional Review Board (IRB) of Noguchi 
Memorial Institute for Medical Research, Accra, Ghana, before the commencement of the 
study. The reference for the ethical approval is: Federalwide Assurance FWA 
00001824; IRB 0001276; NMIMR-IRB CPN 016/09-10 and IORG 0000908). 
 Permission to conduct the study was obtained from the parents/caregivers and headmaster 
and teachers in the school. Informed consent (written and/or oral) was sought from 
selected participants who could express themselves whereas parental assent was sought for 
those participants who could not consent. Participation in the study was absolutely 
voluntary. The purpose of the study as well as the assurance of confidentiality was 
explained to the participants.  
3.8 Dissemination of findings of the study 
The findings of the study were presented at the postgraduate seminar to the Department of 
Nutrition and Food Science, University of Ghana, Accra. The findings of the study will 
also be made available to stakeholders throughout the world through journal publications 
and conferences. The findings were communicated to parents/caregivers and the 
authorities of the study school through a community durbar. 
  
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CHAPTER FOUR 
4.0 RESULTS 
This chapter describes the outcome of the study under the following headings:  Socio-
demographic characteristics, availability and accessibility of vitamin A/carotenoid rich 
foods in the study community, carotenoid content of the intervention diet; serum retinol 
level of the participants and nutritional status of the participants. 
4.1 Socio-demographic characteristics of participants 
The participants were school children aged 6-12 years; comprised of 54.2% males and 
45.8% females (Table 1). In general the children were from intact homes as demonstrated 
by 85.9% of their mothers who revealed that they were married. The fathers of these 
children had higher educational attainments as compared to their mothers. Farming was 
the predominant occupation for both mothers and fathers (Table 1). Although formal 
employment in the households of these participants was relatively low, the majority 
(67.6%) had national health insurance (Table 1). 
 
 
 
 
 
 
 
 
 
 
 
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Table 1: Socio-demographic characteristics of participants (N=142) 
Variable No. of participants 
N 
Percentage  
(%) 
Sex    
   Male 77 54.2 
   Female 65 45.8 
Age    
  6-9 years 102 71.8 
  10-12 years 40 28.2 
Marital Status (Mother)    
  Married 122 85.9 
  Single 8 5.6 
 Widowed 8 5.6 
 Separated 4 2.8 
Educational Level (Mother)   
 No formal education 14 10.0 
  Primary/adult education 55 39.3 
 JSS/Middle school 65 46.4 
 SSS/Technical 6 4.3 
Educational Level (Father)   
  No formal education 5 3.7 
  Primary/adult education 17 12.5 
  JSS/Middle 103 75.7 
  SSS/Technical 11 8.1 
  
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Table 1 Continued 
 
  
Variable No. of participants 
n 
Percentage  
(%) 
 
Occupation (Mother)  
  
  Farming 117 84.2 
  Artisan 6 4.3 
  Salaried worker in government/company 2 1.4 
  Trading 9 6.5 
  Labourer 5 3.6 
Occupation (Father)   
  Farming 76 55.9 
  Artisan 21 15.4 
  Salaried worker in government/company 24 17.6 
  Labourer 15 11.0 
Mother’s monthly income    
< minimum wage (GH¢121) 142 100 
  ≥ Minimum wage ( GH¢121)     0 0 
Father’s monthly  income    
< Minimum wage (GH¢121) 108 76.1 
  ≥ Minimum wage (GH¢121) 29 20.4 
Household Monthly Income   
< Minimum wage (GH¢121) 76 55.5 
  ≥ Minimum wage (GH¢121) 61 44.5 
Household National Health Insurance   
  Registered  96 67.6 
  Unregistered  46 32.4 
The total sample size (N=142) but it changes for some variables because of missing values. 
4.2 Availability and accessibility of vitamin A/carotenoid rich foods in the community 
The first part of the study was a survey on the availability and accessibility of vitamin A-
rich foods in the community. The survey revealed seasonal availability and accessibility of 
vitamin A-rich foods in the community. The study showed that there were no mangoes and 
pawpaw fruits in the community at the time of the survey. There were only a few mango 
and pawpaw trees scattered in the community while palm fruits were either bought or 
gathered from the wild. There was also a scarcity of red palm oil in the community. There 
were however, a number of green leafy vegetables present in the community which were 
mostly seasonal. Hence, green leafy vegetables were available during the raining season 
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while they were non-existent in the dry season. There were generally no food taboos in the 
community which forbade children from eating vitamin A-rich foods. 
4.3 Carotenoid content of the intervention diet 
This was an intervention study using cooked cowpea, gari and palm oil to explore the 
effect of the diet on the vitamin A and nutritional statuses of beneficiaries. HPLC analysis 
of the intervention diet showed that it contained high β-carotene content. Consequently, 
the adequacy of the vitamin A content of the diet in retinol equivalents was also 100% 
(Table 2). 
 
Table 2: Proximate composition, caratenoid and vitamin A content of the 
intervention diet 
Nutrient  Nutrient 
composition/300g 
1/3 DRI (g/day) NAR* (% DRI) 
Moisture (g) 201.60 -  
Energy (kcal) 436.20 ND**  
Carbohydrate (g) 15.33 43.33a 35.38 
Protein (g) 63.36 6.33-11.33b 100 
Fat (g) 13.50 ND - 
Total carotenoids (µg) 7892.25 - - 
β-carotene ( µg) 1935.00 - - 
Vitamin A (µg RE) 823.56 150-200c 100 
*NAR= nutrient adequacy ratio 
**ND = Not determine 
a,b based on Subcommittee on the Tenth Edition of the Recommended Dietary Allowances,  Food and 
Nutrition Board (1989). 
c is the range of recommended safe intakes for age groups similar to those of the participants (6-12 years) 
(FAO/WHO, 2001). 
DRI =Dietary reference intake 
 
 
The macronutrient content of the diet was also assessed in relation to WHO/FAO 
recommended intakes. The macronutrient content of the diet showed that the percent 
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contribution of its protein content was higher than the recommended intake whereas its 
carbohydrate content was below the recommended intake. However, the percent 
contribution of fat to total energy was within recommended intake (Table 3). 
 
Table 3: Energy contribution of macronutrients of the intervention diet relative to 
recommended intakes 
Nutrient  % Energy *Recommended intakes 
(%) 
Carbohydrates  14.06 55-75  
Protein  58.09 10-15  
Fat  27.85 15-30 
*Based on WHO/FAO recommended nutrient intakes (2002). 
4.4 Nutrient intake of participants 
The usual dietary intakes as revealed by 24-hour diet recall showed that the intake of all 
nutrients assessed were significantly different for the pre and post interventions. Total 
energy consumed in the pre intervention was significantly lower than the total energy 
consumed in post intervention, p < 0.001 (Table 4). The mean intake of provitamin A was 
significantly higher in the post intervention period compared to pre intervention p = 0.029 
(Table 4). 
 
  
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Table 4: Nutrient intakes among participants pre-intervention and intervention 
relative to recommended intakes 
Nutrient  Pre-intervention 
 
Post-intervention 
 
P-value 
RDI/day  (Mean ± SD) NAR (% 
RDI met) 
 (Mean ± SD) NAR 
(%RDI 
met) 
Total Energy (kcal) 1800-
2500a 
1860.10± 224.02 100.00 2130.10± 294.89 100.00 <0.001 
% Energy from    
 macronutrientsb 
      
   Carbohydrates (%) 55-75  76.64± 4.83 - 76.20± 6.60  - 0.447 
   Protein (%) 10-15  6.94±1.97 - 8.68±2.39 - <0.001 
   Fat (%)             15-30 16.45± 4.06 - 15.11±5.11 - 0.001 
Macronutrient (g)c       
  Carbohydrate (g) 130 357.76±56.50 100.00 411.36±58.99 100.00 <0.001 
  Protein (g) 19-34 31.86±8.43 93.71-
100.00 
45.64±9.20 100.00 <0.001 
  Fat (g) ND 33.52±7.20 - 35.04±7.44 - <0.001 
Micronutrient (g)d       
  β-carotene (µg) - 46.05 (45.75, 
16999.20) 
- 55.26 (54.90, 
21154.56) 
- <0.029 
  Vitamin A from β-     
carotene (µg RE) 
450-600 3.84 (0.0, 1392.14) 23.44-
31.25 
4.61 (0.0, 1681.79) 31.71-
42.28 
0.029 
 
Statistical significance was taken at p = 0.05 
a, and c is the range of recommended dietary allowance for age groups similar to those of the participants (6-12 
years) (Food and Nutrition Board, 1989). 
bBased on WHO/FAO recommended nutrient intakes (2002). 
d Based on FAO/WHO recommended nutrient intakes (2001). 
 
4.5 Determinants of Vitamin A status among participants 
The vitamin A status of study participants was categorised as a binary variable, thus 
deficient Vitamin A status or normal. Relationships between socio-demographic 
characteristics of study participants and the outcome variable (vitamin A status) were 
explored using univariate logistic regression models. National health insurance was 
identified as one of the variable that was significantly associated with Vitamin A 
deficiency. The likelihood of vitamin A deficiency among children without health 
insurance was about three folds compared to those with valid national health insurance, 
Odds ratio = 2.67, [95% CI=(1.19, 5.99), P=0.02]. The results also show that children in 
households with income below the minimum monthly wage were 73% more likely to be 
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vitamin A deficient compared to children in households with income above the minimum 
wage (Table 5). 
Table 5: Predictors of Vitamin A status among the participants 
Variables  Normal 
n (%) 
Deficient 
n (%) 
Odds 
ratio 
95% CI P-value 
Gender       
  Female  15 (23.1) 50 (76.9) 1   
  Male  17 (22.1) 60 (77.9) 1.06 (0.48, 2.33) 0.89 
Age (years)      
  6-9 16 (21.9) 57 (78.1) 1   
  10-12 16 (23.2) 53 (76.8) 1.08 (0.49, 2.36) 0.86 
Malaria status      
  Positive  19 (20.0) 77 (80.2) 1   
  Negative  13 (28.3) 33 (71.7) 0. 63 (0.28, 1.41) 0.26 
Mother‘s education      
  Some formal education 29 (23.0) 97 (77.0) 1   
  No formal education 3 (21.4) 11 (78.6) 0.91 (0.24, 3.49) 0.89 
Marital status      
  Married  27 (22. 1) 95 (77.9) 1   
  Other  5 (25.0) 15 (75.0) 0.85 (0.28,  2.56) 0.78 
National Health Insurance      
  Yes   16 (16.7) 80 (83.3) 1  (1.19, 5.99) 0.02 
  No 16 (34.8) 30 (65.2) 2.67   
Household Income      
    ≥ Minimum wage 
(GH¢121) 
12 (19.7) 49 (80.3) 1   
< Minimum wage (GH¢121) 19 (25.0) 57 (75.0) 0.73 (0.32, 1.66) 0.46 
HAZ      
  Normal  27 (22. 1) 95 (77.9) 1   
  Stunted  5 (25.0) 15 (75.0) 0.85 (0.28, 2.56) 0.78 
WAZ      
  Normal  31 (23.3) 102 (76.7) 1   
  Underweight  1 (11. 1) 8 (88.9) 2.43 (0.29, 20.20) 0.41 
BAZ      
   Normal  29 (22.7) 99 (77.3) 1   
   Severe  3 (21.4) 11 (78.6) 1.07 (0.28, 4.11) 0.92 
 
4.6 Food consumption pattern among participants 
Data was also collected on the weekly food consumption of the participants. The results 
from the food frequency questionnaire as shown in Table 6 indicated that cereal and grain 
products constituted the major source of energy for the participants. Over 80% of the 
participants consumed diets prepared from cereal/grain on a daily basis. The consumption 
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of roots and tubers was not common with only 22.5% of the participants consuming them 
on a daily basis. The results also showed a low fruit intake among the participants. Nearly 
50% of the participants had not consumed fruits in the week preceding the interview; 38% 
of them consumed fruits 1-3 times a week. Only 2.8% of the participants consumed fruits 
on a daily basis. Vegetable consumption per week was however higher compared to fruit 
intake with 43.7% of the participants consuming vegetables daily. Poultry, meat and fish 
group was consumed on a regular basis. Twenty percent of participants consumed foods 1-
3 times per week from this group whereas 31.7% of them consumed foods from this group 
on a daily basis. Fats and oils had not been consumed by 43% of the participants in the 
week preceding the interview. Furthermore, less than one percent of participants 
consumed diets prepared with items from the fats and oils group daily. The participants 
rarely consumed dairy and dairy products. Over 95% of the participants did not consume 
foods from this group on a weekly basis (Table 6). 
 
Table 6: Weekly food consumption frequency of participants 
Food Group Weekly Consumption 
Never 1-3 Times 4-6 Times ≥7 Times 
n (%) n (%) n (%) n (%) 
Cereals & grains - - 25 (17.6) 117 (82.4) 
Roots & Tubers 11(7.7) 50 (35.2) 48 (33.8) 32 (22.5) 
Legumes & 
Nuts 
44(31.0) 76 (53.5) 19 (13.4) 3 (2.1) 
Fruits 68 (47.9) 54 (38.0) 16 (11.3) 4 (2.8) 
Vegetables  8 (5.6) 25 (17.6) 47 (33.1) 62 (43.7) 
Poultry, Meat & 
Fish 
- 29 (20.4) 68 (47.9) 45 (31.7) 
Fats & Oils 61(43.0) 56 (39.4) 24 (16.9) 1 (0.7) 
Dairy & Dairy 
products 
140 (98.6) 2 (1.4) - - 
4.7 Serum retinol level of the participants 
The mean serum retinol level (12.13 µg/dL) of the participants at pre-intervention was 
significantly different from the mean serum retinol of (16.11 µg/dL) at the post-
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intervention period, p <0.001. The results however showed that the mean serum retinol of 
males did not differ from females in the pre intervention, p = 0.608 and in the post 
intervention, p = 0.975 (Table 7). 
 
Table 7: Serum retinol levels of participants pre and post interventions 
Variable Pre-intervention 
(Mean ± SD) 
(µg/dL) 
Post-intervention 
(Mean ± SD) 
(µg/dL) 
P-value 
Serum retinol  12.13±6.60 16.11±6.41 <0.001 
Sex     
   Male 11.87±5.45 16.13±6.00 <0.001 
   Female  12.44±7.78 16.09±6.92    0.007 
 
 
The association between socio-demographic characteristics of the participants and serum 
retinol was explored in a univariate linear regression model. It was observed that none of 
the reported socio-demographic characteristics was significantly associated with the serum 
retinol of the participants (Table 8).  
 
Table 8: Association between serum retinol and socio-demographic characteristics of 
participants 
Variables  Regression coefficient R-squared P-value 
Mother‘s education 1.041  0.010 0.34 
Mother‘s income 1.002 0.011 0.21 
NHI 1.124 0.022 0.08 
Family size 0.995 0.001 0.69 
 
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The study established the prevalence of vitamin A deficiency (VAD) among the 
participants. VAD was defined using the WHO cut-off of serum retinol concentration < 20 
µg/dL. Therefore, participants with serum retinol concentrations < 20 µg/dL were 
considered deficient while those with serum retinol concentrations ≥ 20 µg/dL were 
considered to be normal. The prevalence of vitamin A deficiency among the participants 
reduced from 95.1% in pre-intervention to 77.5% in post-intervention (Figure 3). 
 
Figure 3: Prevalence of vitamin A deficiency among participants 
The results also showed the prevalence of VAD among female and male participants in the 
study. There was a seventeen percent reduction in VAD among female participants while 
there was an eighteen percent reduction in VAD among males (Figure 4). 
 
4.9
22.5
95.1
77.5
0
10
20
30
40
50
60
70
80
90
100
Pre intervention Post intervention
P
er
ce
n
t
Intervention period
Normal
Deficient
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Figure 4: Prevalence of VAD among participants according to gender 
 
Results from a multi linear regression model explored the joint effect of some indicators of 
nutritional status on the differences in serum retinol observed at the end of the 
intervention. These variables accounted for about 17% of the variability in serum retinol 
(Table 9). WAZ, β-carotene as RE* and BAZ were significantly associated with serum 
retinol with p-values 0.04, 0.05 and 0.03 respectively (Table 9). 
 
Table 9: Association between serum retinol and nutritional status indicators 
Variables  Regression coefficient R-squared P-value 
WAZ 0.892 0.17 0.04 
NHI 0.999 0.17 0.06 
BAZ 1.204 0.17 0.03 
β-carotene as RE* 1.138 0.17 0.05 
*RE = retinol equivalent 
 
6.2 3.9
23.1 22.1
93.9 96.1
76.9 77.9
0
10
20
30
40
50
60
70
80
90
100
Female Male Female Male
Pre intervention Post intervention
p
er
ce
n
t
Intervention period
Normal
Deficient
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4.8 Effect of vitamin A on the occurrence of infection among the participants 
The mean malaria parasite density for the pre intervention was 2923.42±5667.09/µL and 
this was significantly different from the post intervention parasite density of 
865.16±1312.12/µL, p = 0.008 (Table 10).  
 
Table 10: Malaria parasite density of participants pre and post interventions 
Variable Pre-intervention 
(Mean ± SD) (µL) 
Post-intervention 
(Mean ± SD) (µL) 
P-value 
Malaria parasite density 2923.42±5667.09 865.16±1312.12 0.008 
Sex     
   Male 2594.84±3351.81  1090.32±1419.29  
 
0.036  
 
   Female  3252.00±7337.88  
 
640.00±1175.39  
 
0.062  
 
 
The pre and post intervention malaria status did not differ significantly between males and 
females (p = 0.792 and 0.455 respectively) (Table 11). 
 
Table 11: Malaria status of participants pre and post interventions  
Variable Malaria status 
Pre-intervention Post-intervention 
Positive Negative P-value Positive  Negative  P-value 
Sex 
  Male 
 
  n (%) 
 
53 
(37.3) 
 
24 (16.9) 
 
 
0.734 
 
46 (33.1) 
 
30 (21.6) 
 
 
0.345 
  Female 
 
  n(%) 
 
 
43 
(30.3) 
 
22 (15.5) 
 
43 (30.9) 
 
20 (14.4) 
 
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4.9 Nutritional status of the participants 
The study also explored the potential effect of the intervention diet on the nutritional status 
of the participants. Comparisons between the pre and post-intervention nutritional status 
showed a significant difference in height-for-age z-scores (p<0.001). However, there was 
no statistical difference between the pre and post intervention weight-for-age z-scores, 
p=0.941 (Table 12). 
 
Table 12: Nutritional status of participants’ pre and post interventions 
Variable  Pre-intervention Post-intervention P-value 
  Weight (kg) 26.86±7.95 28.59±8.60 <0.001 
  Height (cm) 128.46±15.34 133.15±14.26 <0.001 
  Weight-for-age z-score  (WAZ) -1.05±0.82 -1.04±0.94 0.941 
  Height-for-age z-score (HAZ) -1.24±1.10 -0.871±1.16 <0.001 
  Body mass index-for-age z-score 
(BAZ) 
-0.59±0.92 -0.74±0.98 0.054 
 
The nutritional status of the participants was measured in terms of WAZ (underweight), 
HAZ (stunting) and BAZ (thinness). Undernutrition was defined using z-scores < -2 S.D. 
There was an improvement in the prevalence of stunting. The prevalence of stunting 
reduced from 24.7 in pre-intervention to 14.1 in post intervention (Figure 5). 
 
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Figure 5: Nutritional status of participants pre and post interventions 
 
 
 
 
  
10.1 12.5
24.7
14.1
7.0 9.9
89.9 87.5
75.4
85.9
93.0 90.1
0
10
20
30
40
50
60
70
80
90
100
WAZ WAZ HAZ HAZ BAZ BAZ
Pre-
intervention
Post 
intervention
Pre-
intervention
Post 
intervention
Pre-
intervention
Post 
Intervention
p
er
ce
n
t
Nutrition status indicator
Severe
Normal
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CHAPTER FIVE 
5.0 DISCUSSION 
This was a pre-test-post-test intervention study conducted to explore the effect of gari and 
beans stew prepared with red palm oil on the serum vitamin A and nutritional status of 
school children (6-12 years) in Kodzobi community in the Adaklu-Ayigbe district of the 
Volta Region of Ghana. The study also included a dietary assessment and the effect of the 
intervention diet on infection episodes among the participants. This study was necessitated 
by the long search for a sustainable solution to vitamin A deficiency (VAD) especially 
among children in low income rural households. 
5.1 Vitamin A nutrition and background characteristics of participants 
Demographics and socio-economic characteristics are known to impact on nutritional 
status negatively or positively (Hesketh et al., 2003: Ajao et al., 2010: and Babar et al., 
2010).  It is well documented in the literature that children and women are among the most 
vulnerable in society (Nahar et al., 2010: Ajao et al., 2010 and UNICEF, 2012); and large 
family size increases vulnerability (UNICEF, 2012). Poverty has been identified as the 
single most influential factor on nutritional status (Ajao et al., 2010). However, studies on 
income, level of education and nutritional knowledge as predictors of nutritional status 
have produced conflicting results (Rolland-Cachera et al., 2000; Jackson et al., 2002 and 
Shi et al., 2005).  
 
In this study none of the socio-demographic and the economic variables (maternal 
education and income, household income and family size) was significantly associated 
with vitamin A nutritional status. This finding is similar to the results of a study exploring 
the effect of socio-demographic and health related risk factors for subclinical vitamin A 
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deficiency conducted in Ethiopia among children 6-72 months (Demissie et al., 2009). In 
that study it was found that maternal education categorised as ―illiterate‖ and ―literate‖ 
was not associated with vitamin A nutrition. Similarly, Kidala et al., 2000 found no 
association either between maternal nutrition education and vitamin A or serum retinol 
levels. The present finding which is consistent with literature may suggest that having 
education or being literate does not mean one understands and applies nutrition in 
everyday living. Maternal nutrition education has been found elsewhere to increase the 
consumption of carotene and improve serum retinol concentrations among teenagers 
(Kuhnlein and Burgess, 1997). On the contrary, Vijayaraghavan et al. (1997) documented 
that despite improved knowledge, production and consumption of vitamin A-rich foods 
among children participating in a nutrition education and horticultural controlled trial in 
India, mean serum retinol levels did not improve significantly compared to those of non-
participants. This may imply that there are other factors that are influencing vitamin A 
nutrition.  
 
It is generally known that when income improves, nutrition also improves and this is well 
documented in the UNICEF (1990) malnutrition framework. In the present study, the 
setting indicates an impoverished area, which automatically skews the study population 
into a low socio-economic status which is usually plagued with multifaceted nutritional 
challenges. It is therefore not surprising that in this study there was no significant positive 
association between household income and vitamin A intake and serum retinol levels 
among the participants in univariate logistic regression. Nevertheless, it is noteworthy that 
children in households with incomes below the minimum daily wage (GH¢4.48) in Ghana 
(Ghana News Agency, 2012) were 73% more likely to be vitamin A deficient compared to 
their counterparts in households with income above the minimum wage. 
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In contrast, some studies in developing countries have exposed a clear significant positive 
association between high household income and the intake of vitamin A-rich foods as well 
as serum retinol levels among children (West and Mehra, 2010; and West and Darnton-
Hill, 2008). In spite of the above evidence, it must be reiterated that having high/good 
income does not necessarily translate into consumption of vitamin A rich foods but it must 
be backed with the nutritional knowledge in food choice, selection and nutrient content of 
foods. 
 
Another socio-demographic characteristic that influences nutritional status is family size 
(Babar et al., 2010). Having large family size is something ingrained in the Ghanaian 
culture. The average family size in Ghana according to GSS (2008) is 3.7 with rural 
families consisting of a higher number (4) of persons per household. In the present study, 
family size on the average was 6.1 which is typical of rural Ghana. Having a large family 
size is linked with poverty (Orbeta, 2005; Omonona, 2010) because there are more mouths 
to feed which is a nutritional challenge for many in Ghana and other poor regions across 
the globe. In this study, family size did not significantly affect the intake of vitamin A or 
the serum retinol levels of the children. This finding corroborates the finding of an earlier 
study by Demissie et al. (2009) which established that family size was not associated with 
vitamin A deficiency. From the literature reviewed and the findings of this study it may be 
said that selecting foods rich in vitamin A to feed the family may be a key to improving 
vitamin A nutrition.  
 
 
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5.2 Dietary intake and nutritional status of participants 
In many developing countries where animal source foods are prohibitively expensive or 
non-existent (West, 2000), plant source foods constitutes a significant proportion to the 
overall nutrient intake (Codjia, 2001). In this study, it was found that the nutrient intake of 
the participants was largely obtained from plant sources of food. Analysis of the 24 hour 
dietary recall showed that total energy, carbohydrate and protein needs of the participants 
were adequate for both pre and end interventions. There was also a significant difference 
between the pre and end line intervention intakes of these nutrients. This finding is in 
contrast to the finding of an earlier study by Takyi (1999). In that study, the author 
reported that the total caloric intake of school children in Saboba, a rural setting in 
northern Ghana was inadequate (only 26.5% of RDA) whilst the protein intake among the 
children was adequate with respect to RDA.  Another contradiction to the present study 
was documented in a much more recent study in neighbouring Nigeria where it was found  
that the energy and protein intake of  children of low income earners were inadequate, 
meeting only 72% and 10.42% RDA respectively (Amosu et al., 2011). 
A possible reason which could be credited for the observed difference between the pre and 
post intervention in this study is the evidence that the intervention diet was fortified with 
palm oil which contained an adequate level of fat, a higher energy yielding nutrient 
(Fasina et al., 2006). The other constituents of the intervention diet, cowpea and gari could 
have also contributed to the protein and the carbohydrate intakes of the participants. 
 
Based on the 24 hour dietary recall that was conducted, the vitamin A intake of the 
participants was far lower than the RDI (FAO/WHO, 2001). This was probably because 
the children obtained their vitamin A mainly from green leafy vegetables which contain 
provitamin A (carotenoids) as compared to animal source foods which are richer in 
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vitamin A. This revelation is a reflection of the situation in many countries in sub-Saharan 
Africa as has been reported by some earlier studies (Codjia et al., 2001; Faber et al., 
2002).  Codjia and colleagues in 2001 reported that 80% of the overall intake of vitamin A 
in sub-Sahara Africa is provided by plant sources of food. Subsequently, Faber and co-
workers in 2007 also found that nearly 70% of the vitamin A intake of children in 
KwaZulu Natal, South Africa was obtained from dark green leafy vegetables. These 
studies attributed the high consumption of provitamin A carotenoids to their affordability, 
high availability and diversity. 
 
In the present study setting, major provitamin A rich foods such as mango, pawpaw and 
palm fruit are not widely grown in the community. This made accessibility to these foods 
expensive to buy in the community even when they were in season in the country since 
they had to be transported from other places. As a result, community members relied more 
on dark green vegetables which are not as high or rich a source of vitamin A (Institute of 
Medicine, 2001) for their vitamin A needs. It may therefore be held that the difference 
observed between the pre and post intake of vitamin A was as a result of the red palm oil 
which was a major constituent of the intervention diet.  
 
As described above, the dietary intake of the participants based on the 24 hour and weekly 
recalls demonstrated a general adequacy of macronutrient intake. However, the vitamin A 
intake of the participants was generally lower than the recommended intake. Additionally, 
green leafy vegetables were the major contributor of provitamin A carotenoids. Low 
dietary fat also characterised the diet of the participants, a situation which militates against 
vitamin A absorption (Vijayaraghavan et al., 1997). In the present study, the food 
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frequency results also showed that the daily consumption of fats/oils among the 
participants was low (less than one percent). 
 
Consequently, the recorded difference in serum retinol levels between the pre and post 
interventions is most likely the effect of the intervention diet. This is because β-carotene 
intake based on the 24 hour dietary recall was not found to be significantly associated with 
the serum retinol of the children.  Red palm oil is a rich source of β-carotene which is 
readily convertible to retinol in a fat medium. It could therefore be stated that the fat 
content of the intervention diet provided the appropriate fatty milieu for the absorption of 
the retinol (Vijayaraghavan et al., 1997).  
 
The consumption of animal protein was not routine. For example, dairy and dairy products 
were never consumed by 98.6% of the children in the week preceding the recall. Dry fish 
was the only animal protein which was consumed by only 32% of the participants on a 
daily basis. This may not be enough to account for the differences observed in the serum 
retinol level of the participants. Viewed in another way, the protein that was provided by 
the cowpea also ensured the appropriate levels of amino acids which may be necessary for 
the formation of retinol binding protein which is required in the transport of retinol within 
the body. 
 
The overall significant improvement in the weight and height of the children suggests that 
the intervention diet with respect to the total energy, carbohydrate and fat content 
contributed to the differences observed since the 24 hour dietary recall suggests that the 
children had higher intakes of these nutrients at the end of the intervention compared to 
the pre-intervention intakes. The weight could also be the result of a gain in fat. The high 
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level of provitamin A provided by the RPO in the diet probably also contributed to the 
growth of the children. This observation is consistent with an observation made by West et 
al. (1997) that vitamin A supplementation was found to improve linear growth among a 
cohort of 3377 rural Nepalese children.  
 
The improvement in stunting among the participants may be attributed largely to the 
intervention. The combination of gari and beans and fat from the RPO was a potent tool in 
generating the required nutrients for growth. This finding is consistent with the finding of 
Sedgh et al. (2000) who demonstrated in a longitudinal study that dietary intake of vitamin 
A improved stunting rates and recovery among 8174 Sudanese children. In a much more 
recent study, Kimani-Murage et al. (2012) showed that vitamin A supplementation 
improved stunting among children in Kenya.  
 
The lack of effect of the intervention on weight-for-age could be related to infection-
diarrhoea and malaria which was high among the participants throughout the study. This 
finding is consistent with earlier studies (Griffiths et al., 2004 and Alasfoor et al., 2007) 
which also indicated that in low income settings, low weight-for-age z-scores are 
associated with recent morbidity from diarrhoea. Infections cause anorexia, and 
consequently decreasing nutrient intake.  For instance, children with acute respiratory 
infections or diarrhoea in Guatemala consumed 8% and 18% fewer calories per day, 
respectively, than did asymptomatic children (Stephensen, 2001). 
5.3 Vitamin A status and infection rates among the participants 
The nexus between vitamin A nutrition and health has been well established. The 
influence of vitamin A nutrition on health is observed in both communicable and non-
communicable diseases (Slattery et al., 2000; Stephensen, 2001). For instance, diarrhoea, 
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pneumonia, and measles are frequently observed prior to or with xerophthalmia (Sommer 
and West, 1996). The link between vitamin A deficiency and infection has been observed 
in retrospective, case-control studies among pregnant women and also in longitudinal, 
observational studies conducted among children (Stephensen, 2001). These medicinal 
properties of vitamin A are occasioned by its role in immune function (Stephensen, 2001).   
 
In the present study, the association between vitamin A and malaria was explored. Vitamin 
A has been identified to be an anti malarial agent due to its inhibition of the growth of the 
Plasmodium falciparum in vitro (Hamzah et al., 2003). The mechanism of this influence is 
not well understood. However, the Plasmodium falciparum, appears to gather vitamin A 
from its host and concentrate it in the cytoplasm of late trophozoites for use as an 
antioxidant. This may partially account for the hypovitaminosis A observed in malaria 
patients (Mizuno et al., 2003). In this study a 30% reduction in malaria parasite density 
between pre and post intervention was recorded. Accordingly, the reduction in the malaria 
parasite density between pre and post intervention levels may be attributed to the adequacy 
of the vitamin A provided by the intervention diet. This assertion is supported by some 
studies in other parts of the developing world. In Papua New Guinea, Vitamin A 
supplementation among children reduced the frequency of malaria attacks by 30% and cut 
down the malaria parasite density by as much as 36% (Shankar et al., 1999). Similarly 
Zeba et al. (2008) reported a 30% reduction in malaria among supplemented children from 
neighbouring Burkina Faso.  In the Congo, a case control study among pre-schoolers 
revealed that 37.5% of the children suffering from malaria had lower than 10 μg/dl (0.3 
μmol/L) plasma retinol levels (Galan et al., 1990). Another factor that could account for 
this difference was health and nutritional conditions in the community which did not 
improve during the intervention.  
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The only factor which significantly translated into improvements in vitamin A status in 
this study was accessibility to healthcare (for which access to National Health Insurance 
was used as a proxy). This was probably because access to health insurance resulted in 
affordable and early attendance to health facility and hence timely treatment of infections 
such as malaria and diarrhoea which tend to undermine vitamin A nutrition. Children from 
households without health insurance were three times more likely to be vitamin A 
deficient compared to children from households with health insurance. There is a dearth of 
information on the direct effect of having health insurance on vitamin A status. However, 
population based studies suggest that access to healthcare can improve nutrition status of 
children (WHO, 2001; Babar et al., 2010; Srivastava et al., 2012). 
5.4 Implications of the study for nutrition and health 
The findings of this study have several implications for clinical as well as public health 
practice within the study location and beyond. The study showed that the intervention diet 
was effective in lowering stunting among the participants. This knowledge can be 
harnessed in designing appropriate dietary regimen for school children at risk of chronic 
malnutrition. The study also demonstrated the potential of red palm oil in reducing malaria 
parasite density. Therefore, in addition to routine malaria medication health workers 
should also emphasise the need for adequate dietary intake of vitamin A. In this light, 
community members should be advised to improve the cultivation of vitamin A rich foods 
such as mangoes, ―kontomire‖, and palm oil among others.  The study has also revealed 
that red palm oil can be used as a means of combating vitamin A deficiency (VAD) among 
vulnerable rural children. Hence, the study will help to enhance the quality of nutrition 
education messages among health workers.  In a broader national perspective, this study 
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can boost the quality of interventions such as the Ghana School Feeding Programme 
(GSFP).  
 
In all of these considerations, it is very important to note that vitamin A does not work in 
isolation. Accordingly, in addressing vitamin A deficiency related nutrition challenges, 
other issues such as family size, nutrition education, income and infections must all be 
tackled in a holistic manner. 
5.5 Limitations of the study 
Although the study was done with caution within the limits of both human and 
experimental errors, it is important to reiterate unavoidable limitations that may have 
implications on the findings. The results show that the vitamin A status and nutritional 
status of children improved between pre and end intervention. It must however be borne in 
mind that without the benefit of a control group, it was difficult to determine the 
independent contribution of the intervention. Setting up a control group is not simple (De 
Pee et al., 2000; Habicht et al., 1999). In this respect, it is hard to completely attribute the 
successes found to the intervention alone. The use of a convenient sample size might have 
introduced bias in the findings since the sample might not have been representative of the 
population. By extension, this also limits the generalisability of the findings of the study.  
 
Recall bias might have influenced the process of recall of foods eaten during the past 7 
days. Also, the use of the 24-hour recall might not be representative of usual daily nutrient 
intake of the participants. Hence, measurement bias in measuring nutritional intake could 
have contributed to some amount of bias in this study. Recall bias was especially likely in 
this study since the participants were children. As a result, the estimated nutrient intake 
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may have been higher or lower than the usual intakes of the participants. Perhaps a better 
method for the dietary assessment may have been weighed food intake (Trabulsi and 
Schoeller, 2001). 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
  
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CHAPTER SIX 
6.0 CONCLUSIONS AND RECOMMENDATIONS 
6.1 Conclusion 
From the current study, the following inferences may be made: 
 Dietary intake of vitamin A rich foods among the participants in the study was 
poor and this was due to seasonality and accessibility of pro-vitamin A rich foods 
such as mangoes, pawpaw, palm oil and green leafy vegetables in the community. 
However, their intake of macronutrients (carbohydrate, fats and proteins) seemed 
adequate from the dietary recall but did not reflect in the anthropometric indicators 
which showed otherwise with high levels of wasting and underweight.   
 The prevalence of Vitamin A Deficiency (VAD) among the participants was as 
high as 95.1% in the pre-intervention. At the end the intervention, the prevalence 
of VAD remained as high as 77.5% clearly indicating that vitamin A deficiency is 
a public health challenge in the study population. The prevalence of VAD was 
higher among the male participants than it was among the female participants.  
 The 300g intervention diet contained 823.56 µg RE and this contributed 
significantly to the mean serum retinol level of 16.11±6.41 µg/dL at the end of the 
intervention. 
  In this study the 30% reduction in malaria parasite density between pre and post 
intervention could be attributed to the consumption of vitamin A rich palm oil.  
 
 Clearly then,  feeding  children with gari and beans stew prepared with red palm 
oil three times a week may be a long term sustainable food based strategy in the 
battle against vitamin A deficiency.  
 
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6.2 Recommendations 
Further research  
 There is the need for further research using a control group and a larger sample 
size to explore the effect of red palm oil and cowpea based diets on the vitamin A 
and nutritional status among children. Such studies should also be conducted over 
a longer period (at least one year). 
 Future studies should also be community based in order to test the effectiveness of 
red palm oil in addressing vitamin A deficiency.  
Policy for public health practice 
 In the short term, there is the need for horticultural practices such as home 
gardening among residents to increase the production of vitamin A-rich fruits and 
vegetables. 
 In view of the low consumption of vitamin A-rich foods in the study community, 
health education and promotion activities should be intensified by the Ghana 
Health Service (health workers) to ensure higher consumption of especially 
vitamin A rich fruits and vegetables as well as red palm oil among children in the 
community.  
 In the long term, the participation of agricultural extension officers may also be 
required to ensure the production of vitamin A food trees such mangoes and oil 
palm in the community.  
 The consumption of gari and beans stew prepared with red palm oil three times per 
week is recommended among children to improve vitamin A status. This may be 
applied in the Ghana School Feeding Programme and similar programmes. 
 
 
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APPENDICES 
APPENDIX I: QUESTIONNAIRE 
 
QUESTIONNAIRE FOR CHILD AND PARENTAL BACKGROUND FOR  THE 
STUDY - SERUM VITAMIN A AND NUTRITIONAL STATUS OF CHILDREN 
FED GARI AND BEANS STEW 
 
Questionnaire number……………………..                       Date of interview…………….. 
A. Socio-demographic data 
Child data 
1. Name of Child…………………………….…..      2.  Sex ………………………… 
3. Age of child……………………………………    4. Date of birth (DOB)………… 
5. Source of verification of DOB (e.g. birth certificate, growth monitoring card etc) 
……………………………………………………………………………………..……  
6. Name of School……………..……….. 
7. Class…………………………………        8. Number of siblings under five………. 
Parental data 
Father 
9. Age (in years) a. less than 20 b. 20-25 [ ] c. 25-30 [ ] d. 31-35 [ ] e. 36-40 [ ]  f. 41-
45 [ ] g. 46-50 [ ] h. 51-55 [ ]  i. 56-60 [ ]  j. 61-70 [ ]  k. 71+ [ ]  
10. Marital status a. single [ ] b. married [ ]  c. Separated [ ]  d. divorced [ ]                       
e. Widowed [ ]  f. Other (specify)…………………..…….  
11. How many wives or partners do you have?........................................................... 
12. Educational status a. No formal education [ ]  b. Primary [ ] c. JHS/Middle School 
[ ] d. SSS [ ] e. Training college  [ ] f. Vocational/Technical [ ] g. University [ ] 
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13. Primary Occupation a. Farmer [ ]  b. Trader [ ]  c. Teacher [ ]  d. Fisherman[ ]            
d. Other (specify)………. 
14. Secondary Occupation Farmer [ ]  b. Trader [ ]  c. Teacher [ ]  d. Fisherman [ ]            
e. Other (specify)………. 
15. Religion a. Christian [ ] b. Traditionalist [ ] c. Islam [ ] d. Buddhist [ ] d.  Other 
(specify). 
Ethnicity a. Ewe b. Akan   c. Ga   d. Fante  e. Other (specify)…………………… 
16. Monthly income 
 
 Mother 
17. Age (in years) a. less than 20 b. 20-25 [ ] c. 25-30 [ ] d. 31-35 [ ] e. 36-40 [ ]  f. 41-
45 [ ] g. 46-50 [ ] h. 51-55 [ ]  i. 56-60 [ ]  j. 61-70 [ ]  k. 71+ [ ] 
18.  Marital status a. single [ ]  b. married [ ]  c. Separated [ ]  d. divorced [ ]                         
e. Widowed [ ]  other (specify)……………………………. 
19. How many partners do you have?  ………………………… 
20. Educational status                                                                                                                   
a. No formal education[ ]  b. Primary [ ] c. JHS/Middle School [ ] d. SSS [ ]                
e. Training college  [ ] f. Vocational/Technical [ ] g. University [ ] 
21. Primary Occupation a. Farmer [ ]  b. Trader [ ]  c. Teacher [ ]  d. Fish monger             
e. Other (specify)………………………………………..…. 
22. Secondary Occupation Farmer [ ] b. Trader [ ]  c. Teacher [ ]  d. Fish monger                
e. Other (specify)……………………………………..……. 
23. Religion a. Christian [ ] b. Traditionalist [ ] c. Islam [ ] d. Buddhist [ ] d.  Other 
(specify). 
24. Ethnicity a. Ewe  b. Akan   c. Ga   d. Fante  e. Other (specify)…………………… 
25. Monthly income……………………………. 
26. National health Incurance status of child 
a.  Registered     b. Unregistered  
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B. Child Health/Nutrition 
27. Have you fallen sick in the past two weeks? Yes [ ] No[ ] (please consult parents 
to confirm) 
28. If you answered ‗yes‘ to question, what disease was it? A. malaria b. diarrhea c. 
dysentery d. catarrh ........................................... 
29. Have you received Vitamin A capsule before?          Yes [ ]  No [ ] 
30. What was the colour of the capsule you received? a. Blue [ ]   b. Red [ ]  c. Other 
(specify)……  
31. If yes for vitamin A supplementation how many times?..................... 
32. Iron supplementation status               Yes [ ] No [ ] 
33. If you answered ‗yes‘ for iron supplementation how many times have you received 
it?.....................  
34. Have you received a dewormer in the last 3 months? Yes [ ] No [ ] (please check 
with parent/teacher to confirm) 
35. What type of salt do you/your parents use to prepare your meals at home? a. rocky 
salt[ ]  b. Annapurna [ ] c. Other (specify)………………………… 
 
 
C. Water and Sanitation 
36. What is your source of drinking water? a. Bore hole [ ] b. Well [ ] c. Dam [ ]               
d. Tap [ ]  e. Other (specify)…………………………………..….. 
37. How do you dispose your refuse a. refuse dump [ ] b. Dust bin [ ] c. Refuse tank [ ]  
d. dugout Pit [ ] e. other (specify)……… 
38. Where do you ease yourself? a. home [ ] KVIP b. [ ] Water closet [ ] c. free range 
pit latrine [ ] d. home bucket latrine [ ] e. public toilet[ ] 
 
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D. Cultural Practices 
39.  Do you have any food taboos in your community? Yes [ ] No [ ] 
40. If your answered ‗yes‘ to question 36, what are these foods? 
……………………………………………………………………………………… 
………………………………………………………………………………………
……………………………………………………………………………………… 
41. Why are children forbidden from eating these foods?............................................... 
…………………………………………………………………………………………
…………………………………………………………………………………………
………………………………………………………………………………………… 
  
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E. Food Frequency Questionnaire 
Food More 
than 
once/day 
Once/day No. of  
times/week 
Seldom Never 
Animal and Animal Products 
Fish      
Milk      
Eggs      
Poultry      
Meat      
Wole/ayikoko      
Crab      
Mushroom      
Dark Green Leafy Vegetables 
Ayoyo      
Nkontomire      
Allefu      
Garden eggs      
Tomatoes      
Bean leaf      
Carrots      
Cabbage      
Okro      
Other vegetables      
 
Fruits 
Mango      
Pawpaw      
Orange      
Banana       
Guava      
Watermelon      
Cereals/Grains 
Maize      
Rice       
Millet      
Guinea corn      
Legumes 
Cowpea       
Groundnuts       
Soy beans      
Bambara 
groundnuts 
     
Other (specify)      
Roots and Tubers 
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Sweet potato      
Cocoyam       
Yam       
Cassava      
Plantain       
Fats and Oils      
Palm oil       
Palm kernel oil       
Groundnut oil      
Shea butter      
Other (specify)      
Other foods 
Toffees      
Ice cream      
Biscuits      
Meat pie/doughnuts       
Koose/Agawu      
Roasted plantain      
Fried plantain      
Roasted cassava      
Vitamin, herbs  and 
other supplements 
     
Drinks 
Asana      
Fruit Juice      
Coke, fanta etc 
Other (specify) 
     
 
 
  
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F. 24 Hour Dietary Recall 
 
Meal Type Foods and Beverages consumed. 
Describe in detail.  
Amount Eaten (g) 
or L 
 
Serving Description(Cup, 
Teaspoon, Slice, Finger, 
Fist, Tablespoon) 
Morning      
Mid‐Morning        
Noon    
Afternoon    
Evening    
Late evening    
 
 
 
G. Anthropometry of Child 
Characteristics Measurement  
 1 2 3 
Weight (kg)      
Height (cm)     
 
  
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APPENDIX II: CONSENT FORM 
CONSENT FORM 
 
 
DIETARY INTERVENTION ON SERUM VITAMIN A AND NUTRITIONAL STATUS 
OF CHILDREN 
 
   
 
Introduction 
(This form provides adequate information about the above study to help you make an 
informed decision about your participation in the study. We therefore entreat you to read (or 
have read to you) the information contained in the form. After you have studied the 
information contained in the form, you will be required to sign/initial it (in the presence of a 
witness) if you wish to participate in our study. A copy of the signed form will be given to you 
for your reverence. You will also be asked to sign it (or make your mark in front of a witness). 
Please feel free to ask us to explain anything you may not understand in the form).  
 
Purpose/General Information about Study  
The main objective of this study is to determine the effect of cowpea and palm oil based diets 
on the serum vitamin A and nutritional status of school children. Hence, we will assess your 
food intake, weight, height and mid-upper arm circumference. We will also draw 5ml of blood 
from you to enable us determine the effect of the intervention on the serum vitamin A as well 
as the nutritional status of the school children. If you and your parent/guardian agree to 
participate in the study, we will only spend 45 minutes of your time at your convenience. 
 
Possible Risks and Discomforts 
This study poses little (in terms of blood collection) or no discomforts other than giving us 
thirty minutes of your time.  
 
Possible Benefits 
There may be no direct benefit to you for your participation in our study. However, the results 
of the study will benefit society.  
 
Confidentiality 
We assure you that any information you may provide will be protected and used solely for 
academic purposes and will be treated confidentially. Your name will not be in any of our 
reports. However, a member of the IRB may want to ask you questions concerning your 
participation in the study. Should this happen, you may choose not to respond to such 
questions. A competent court of law could order medical records shown to other people, but 
this is not likely to happen in this study. 
 
 
 
Compensation 
This is student research and as such, it is budget constrained. We are therefore unable to pay 
you any compensation for your participation in our study.  
 
 
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Leaving the Study 
You are free to withdraw from our study at any time if you choose to participate in it.  
 
 If You Have a Problem or Have Other Questions/Concerns 
Please call Dr Matilda Steiner-Asiedu on telephone number 0541260704/0266142105 if you 
have questions about the study. 
 
Your rights as a participant 
This study has been reviewed and approved by the IRB of the Noguchi Memorial Institute for 
Medical Research at the University of Ghana, Legon.  An IRB is a committee that reviews 
studies in order to ensure the protection of participants. If you have any questions about your 
rights as a participant you may contact (Rev. Dr. Ayete-Nyampong, Chairperson, NMIMR-
IRB, mobile 0208152360) 
 
 
Participant Agreement 
This form which describes the benefits, risks and procedures for the study “Dietary 
Intervention on Serum Vitamin A and Nutritional Status of Children” has been read and 
explained to me. All my questions/doubts about the study have been addressed to my 
satisfaction. I therefore agree to participate in the study. 
 
 
 
 
___________________________                           __________________________________                
Date                                                                          Signature or initials of participant 
 
 
 
If volunteers cannot read the form by themselves, a witness must sign here: 
 
I certify that the benefits, risks and procedures of the study were read and explained to the 
participant in my presence. All questions/doubts were addressed to the participant‘s 
satisfaction and the participant has agreed to take part in the study. 
 
 
_______________________                                         _______________________________ 
Date                                                                               Signature of Witness 
 
 
I certify that the nature and purpose, the potential benefits, and possible risks associated with 
participating in this study have been explained to the above individual. 
 
 
 
_______________________                                      ___________________________________ 
Date                                                                       Signature of Person Who Obtained Consent 
 
 
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APPENDIX III: SURVEY CHECKLIST 
 
SURVEY CHECKLIST FOR AVAILABILITY AND ACCESSIBILITY OF 
VITAMIN A RICH FOODS IN KODZOBI COMMUNITY 
 
Food Availability 
Yes,  no, seasonal or all year 
round 
Price 
 
Animal and Animal Products 
Fish   
Milk   
Eggs   
Poultry   
Meat   
Vegetables 
Wole/ayikoko   
Mushroom   
Ayoyo   
Nkontomire   
Allefu   
Tomatoes   
Bean leaf   
Carrots   
Other vegetables   
Fruits 
Mango   
Pawpaw   
Orange   
Banana    
Guava   
Watermelon   
Fats and Oils 
Palm oil    
Other (specify)   
 
 
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APPENDIX IV: MAP OF STUDY AREA 
 
 
Map of Ghana                            Map of study setting  
 
 
Volta Region 
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