Sex-specific responses to zinc supplementation in Nouna, Burkina Faso.

OBJECTIVES

To study the different responses by sex to zinc supplementation among young children. STUDY CHILDREN AND METHODS: Double-blind randomized controlled trial of zinc supplementation in 686 children aged 6-30 months, conducted in Nouna, a rural area of Burkina Faso. Children received either a 12.5-mg zinc sulfate tablet or a placebo every day for about 6 months. Outcomes were morbidity, nutritional status, and mortality.

RESULTS

Results revealed significant differences between boys and girls in their responses to zinc supplementation. Boys who received the zinc preparation had fewer days with diarrhea than did control boys (RR = 0.88, P = 0.05), especially less nonfebrile diarrhea (RR = 0.72, P < 0.001) and less dysentery (RR = 0.65, P = 0.05), but more ear infections (RR = 4.00, P < 0.001). By contrast, girls who received the zinc supplement had the same prevalence of diarrhea as did control girls, but more dysentery (RR = 3.70, P < 0.001), fewer ear infections (RR = 0.39, P < 0.001), and fewer eye infections (RR = 0.41, P < 0.001). The effect of supplementation on nutritional status was not detectable in boys, but girls who received supplementation experienced a faster growth velocity in height than did control girls (P = 0.004) and a faster growth velocity for weight and height if they were wasted and not stunted at baseline (P = 0.003).

CONCLUSIONS

Zinc supplementation had positive, nil, or negative effects depending on pathological condition, and the effects were different for boys than for girls.