Vitamin A and anthropometric status of South African preschool children from four areas with known distinct eating patterns.

OBJECTIVE: The aim of this study was to assess the vitamin A and anthropometric status of South African preschool children from four areas with known distinct eating patterns. METHODS: Serum retinol, anthropometric indicators, and dietary intake were determined for randomly selected preschool children from two rural areas, i.e. KwaZulu-Natal (n = 140) and Limpopo (n = 206); an urban area in the Northern Cape (n = 194); and an urban metropolitan area in the Western Cape (n = 207). RESULTS: Serum retinol <20 µg/dL was prevalent in 8.2% to 13.6% children. Between 3% (urban-Northern Cape) and 44.2% (rural-Limpopo) children had received a high-dose vitamin A supplement during the preceding 6 mo. Vitamin A derived from fortified bread and/or maize meal ranged from 65 µg retinol activity equivalents (24%-31% of the Estimated Average Requirement) to 160 µg retinol activity equivalents (58%-76% Estimated Average Requirement). Fortified bread and/or maize meal contributed 57% to 59% of total vitamin A intake in rural children, and 28% to 38% in urban children. Across the four areas, stunting in children ranged from 13.9% to 40.9%; and overweight from 1.2% to 15.1%. CONCLUSION: Prevalence of vitamin A deficiency was lower than national figures, and did not differ across areas despite differences in socioeconomics, dietary intake, and vitamin A supplementation coverage. Rural children benefited more from the national food fortification program in terms of vitamin A intake. Large variations in anthropometric status highlight the importance of targeting specific nutrition interventions, taking into account the double burden of overnutrition and undernutrition.

Point-of-use micronutrient fortification: lessons learned in implementing a preschool-based pilot trial in South Africa.

This current pilot trial assessed the feasibility of implementing a point-of-use (PoU) micronutrient fortification in preschool settings. Preschool children (n = 151) aged 36-79 months were randomized into intervention (n = 76) and control (n = 75) groups, both receiving breakfast maize-porridge with added micronutrient or placebo powder for 52 school days. Process evaluation and early childhood development indicators were used to assess trial feasibility. Process evaluation results showed that the implementation components were feasible and could be delivered with high fidelity. The improvement in hemoglobin concentration in intervention and control groups were not significantly different (P = 0.250). There was medium likelihood for practical significance for the two global cognitive scores assessed: non-verbal index (intervention effects: 7.20; 95% confidence interval: 2.60, 11.81; P = 0.002, effect size: 0.55) and mental processing index (intervention effects: 2.73; 95% confidence interval: 0.25, 5.70; P = 0.072, effect size: 0.36) on the Kaufman Assessment Battery for Children, Second Edition. The lessons from this trial could help in planning/implementing future PoU micronutrient fortification trial among South African preschool children.

A micronutrient powder with low doses of highly absorbable iron and zinc reduces iron and zinc deficiency and improves weight-for-age Z-scores in South African children.

Micronutrient powders (MNP) are often added to complementary foods high in inhibitors of iron and zinc absorption. Most MNP therefore include high amounts of iron and zinc, but it is no longer recommended in malarial areas to use untargeted MNP that contain the Reference Nutrient Intake for iron in a single serving. The aim was to test the efficacy of a low-iron and -zinc (each 2.5 mg) MNP containing iron as NaFeEDTA, ascorbic acid (AA), and an exogenous phytase active at gut pH. In a double-blind controlled trial, South African school children with low iron status (n = 200) were randomized to receive either the MNP or the unfortified carrier added just before consumption to a high-phytate maize porridge 5 d/wk for 23 wk; primary outcomes were iron and zinc status and a secondary outcome was somatic growth. Compared with the control, the MNP increased serum ferritin (P < 0.05), body iron stores (P < 0.01) and weight-for-age Z-scores (P < 0.05) and decreased transferrin receptor (P < 0.05). The prevalence of iron deficiency fell by 30.6% (P < 0.01) and the prevalence of zinc deficiency decreased by 11.8% (P < 0.05). Absorption of iron from the MNP was estimated to be 7-8%. Inclusion of an exogenous phytase combined with NaFeEDTA and AA may allow a substantial reduction in the iron dose from existing MNP while still delivering adequate iron and zinc. In addition, the MNP is likely to enhance absorption of the high native iron content of complementary foods based on cereals and/or legumes.

Rosa roxburghii supplementation in a controlled feeding study increases plasma antioxidant capacity and glutathione redox state.

BACKGROUND: Rosa roxburghii (RR) is a plant of which the fruit juice has been used as a medicinal remedy for a variety of diseases. It has been proposed that the putative beneficial properties are related to its antioxidant potential. AIM OF STUDY: We investigated the contribution of a supplemented RR fruit sample on the antioxidant status in a cohort of healthy humans. METHODS: A total of 36 young, healthy and non-smoking individuals were recruited for this randomised placebo-controlled, single-blind trial. The study was diet controlled over a five-week period with a two week run-in period before participants daily received a placebo or an encapsulated supplement of RR sample. Total antioxidant capacity, glutathione redox state, glutathione reductase, glutathione peroxidase, superoxide dismutase and 8-OHdG levels were measured. RESULTS: RR supplementation significantly increased plasma antioxidant capacity (p = 0.04) and GSH:GSSG ratios in blood (p = 0.03). No significant changes in 8-OHdG levels, total glutathione levels or antioxidant modulating enzymes were detected suggesting that the observed shift of the glutathione redox state probably occurs via the antioxidant mediated protection of GSH. CONCLUSIONS: We conclude that these findings support the putative beneficial properties that have been linked to Rosa roxburghii as a dietary supplement that can enhance antioxidant status.