Effect of ascorbic acid rich, micro-nutrient fortified supplement on the iron bioavailability of ferric pyrophosphate from a milk based beverage in Indian school children.

Abstract

Nutritional anemia is a significant public health issue with 50-80% prevalence in Indian children. Fortification of food, specifically milk, with iron is a potential approach to increase dietary iron intake. Ferric pyrophosphate [Fe4(P2O7)3] is organoleptically neutral and is less soluble in acid medium and, further, has low bioavailability in milk. However, since ascorbic acid is a potent enhancer of iron absorption, the coadministration of ascorbic acid with Fe4(P2O7)3 might enhance the absorption of iron. We evaluated the effect of ascorbic acid on iron absorption from a Fe4(P2O7)3 and an ascorbic acid fortified milk beverage with respect to milk fortified with Fe4(P2O7)3 alone. A double-blind, two-way crossover, randomized study was conducted in 25 mildly anemic children. The test group received milk fortified with beverage powder containing 7 mg isotopically labeled iron (57Fe/58Fe) as Fe4(P2O7)3, equimolar proportions of ascorbic acid and 200 mg of calcium whereas control group received milk fortified with energy, calcium and iron equivalent beverage powder. Fractional iron absorption was measured by erythrocyte incorporation of stable isotopes of iron (57Fe/58Fe) in both the groups. The fractional iron absorption from the control drink was 0.80% (95% CI: 0.57, 1.12). Fortifying the milk with an equimolar amount of ascorbic acid increased the fractional iron absorption almost 2-fold to 1.58% (95% CI: 1.13, 2.22). The presence of ascorbic acid in an equimolar ratio with that of iron from Fe4(P2O7)3 salt in milk as a fortificant enhanced iron absorption when compared to milk fortified with only Fe4(P2O7)3.