The Effect of Zinc-Supplemented Bread Consumption on School Children with Asymptomatic Zinc Deficiency

Abstract

The results indicate that the bioavailability of zinc in the bread is satisfactory. The use of zinc-fortified bread was found to be an economical and readily accessible method to eliminate zinc deficiency and to prevent further occurrence.

Systematic Review of Zinc Fortification Trials

“…Our search strategy, including manual search, identified eleven studies, seven of which were on infants [17,18,19,20,21,22,23] where infant formula feeds or milk were fortified, three were on school children where porridge or bread was fortified [24,25,26], while one study was on women of reproductive age [27]. Nine of the studies were randomized controlled trials while two [20,26] were quasi-experimental designs.…”

“…Five studies [17,18,19,23,27] employed zinc sulfate as the fortification compound. Other compounds used were zinc oxide [24], zinc chloride [22] and zinc acetate [25]. All included studies compared zinc-fortified food with control groups with no fortification.…”

“…The characteristics of the studies are summarized in table 1 and risk of bias assessment is presented in table 2. The most commonly reported outcomes were serum zinc concentration [17,18,19,20,21,22,24,25,26], hemoglobin level [18,22,25], alkaline phosphatase [21,23,25], serum copper concentration [20,22,23,25], weight gain [17,18,20,22,23,24] and linear growth or height velocity (growth in mm/day) [17,18,20,21,22,23,24]. The study by Brown et al [17] also looked at the effect of zinc fortification on episodes of diarrhea, flu-like symptoms, pneumonia and other illness during the period of intervention.…”

“…Results from nine trials [17,18,19,20,21,22,24,25,26] showed that there was a significant impact of zinc fortification on serum zinc concentration, with individual impacts ranging from 0.08 (95% CI -0.65, 0.81) to 5.51 (95% CI 3.91, 7.11) and a combined SMD of 1.28 (95% CI 0.56, 2.01). The heterogeneity was high (p < 0.00001; I 2 = 89%), hence a random effect model was used.…”

“…Three studies with a total of 119 children evaluated the impact of zinc fortification on the alkaline phosphatase activity; two studies examined healthy infants [21,23], while one study had asymptomatic zinc-deficient school children as a study population [25]. The pooled analysis had a net SMD of 0.94 (95% CI -0.29, 2.17) (fig.…”