Prevalence of Zinc Deficiency among Ghanaian Adolescents versus Food Components of Zinc and Phytate

Abstract

Zinc is an essential micronutrient found in almost every cell in the body. Nutrient needs are highest during adolescence, surpassed only by needs during pregnancy and lactation. The aim of this study was to determine the prevalence of zinc deficiency among adolescents in Ghana and to relate this with dietary intake of zinc and phytate. A total of 300 adolescents between ages 13-19 years were recruited from the Greater Accra and Upper East Regions for the study. Questionnaires were used for background data collection as well as food frequency intake. Anthropometric measurements were taken and plasma zinc assessed. A 46% overall prevalence of zinc deficiency (i.e. Plasma zinc <80μg/dL or <12.3μmol/L) was detected with southern subjects having a significantly higher prevalence (51%) than northern subjects (42%), (P≤ 0.05). Mean plasma zinc concentration detected was 81.42± 26.84 for the south and 82.96 ± 16.27 for the north. Males also had a higher prevalence of zinc deficiency than females though this was not statistically significant (p<0.05). The highest zinc - containing foods among the most frequently consumed foods in the north were dry fish (11.2mg/100g), groundnuts (4.5-4.7mg/100g), millet (4.7mg/100g), whole maize (3.3mg/100g) and unpolished rice (2mg/100g) and for the south, they were fish (10.9-ll.3nng/100g), beef (4.1mg/100g), milk (3mg/100g), poultry (2.8mg/100g) and maize (2.4mg/100g). Highest phytate containing foods among the most frequently consumed foods were groundnut (546.1- 622.5mg/100g), maize (211.5-608.3mg/100g), millet (587.5mg/100g), unpolished rice (219.7mg/100g), and green leafy vegetables (146.5mg/100g) for the north and maize (615mg/100g), cowpea (600mg/100g), and groundnut (540mg/100g) for the south. The level of zinc deficiency found in this cohort clearly indicates that zinc deficiency is a public health problem in Ghana especially among adolescents. The possible contribution of dietary factors like low intake of zinc and its anti-nutritional factors merits a proper and broader look as well. An intervention by policy makers in the country may be necessary.