Zinc and Iron Bioavailability From Biofortified Pearl Millet

Nutritional deficiency of iron in 30-70% of young children in different communities in India is well documented and has proved challenging to eradicate both in India and globally. Less is known about zinc deficiency, but zinc and iron are generally present in the same foods and there is also growing evidence for the public health importance of zinc deficiency in young children on a global basis. In populations that depend primarily on plant-based foods, biofortification of major food staples by traditional selective plant breeding procedures offers an attractive strategy for preventing iron and zinc deficiency in all age groups. Pearl millet, a major food staple in several areas of India, has both naturally relatively high concentrations of iron and zinc with demonstrated potential to increase these levels further with plant breeding. Before embarking on complex, costly efficacy, effectiveness studies of the potential health benefits of this biofortified grain, the objective of this project is to determine the extent to which iron and zinc absorption is increased in very young children who consume pearl millet as the primary grain and major food staple. This is a short term, cross-sectional double-blinded study in which the test or control pearl millet is fed for a total of 9 days. Primary outcome measures are the increases in iron and zinc absorption over a two-day period. Test meals will be labeled with a zinc stable isotope on Day 8 and an iron stable isotope on Days 8 and 9 during which days participants and their mothers will stay in their community health center. Food intake will be weighed and duplicate diets obtained. Percentage iron absorption will be determined from erythrocyte enrichment on Day 23. Fractional zinc absorption will be measured from urine enrichment with orally and intravenously administered zinc isotopes from timed samples collected on Days 12-15. Daily absorption of these minerals will be determined. Increases in intake and absorption of these minerals (mg/d) will be evaluated with respect to estimated dietary and physiologic requirements.