Revisiting Dietary Iron Requirement and Deficiency in Indian Women: Implications for Food Iron Fortification and Supplementation.

Anemia in Indian women continues to be highly prevalent, and is thought to be due to low dietary iron content. The high risk of dietary iron deficiency is based on the Indian Council of Medical Research recommendation of 21 mg/d, but there is a need for a secure and transparent determination of the Estimated Average Requirement (EAR) of iron in this population. In nonpregnant, nonlactating women of reproductive age (WRA), the EAR of iron was determined to be 15 mg/d. Applying this value to daily iron intakes among WRA in nationally representative Indian state-based data showed that the median risk of dietary iron deficiency was lower than previously thought (65%; IQR: 48-78%), with considerable heterogeneity between states (range: 25-93%). However, in a validation, this risk matched the risk of iron deficiency as defined by blood biomarkers in a recently completed survey. When the risk of dietary iron deficiency was modelled for an increase in iron intake through food fortification of a single dietary staple, that provided 10 mg/d, the median risk reduced substantially (from 65% to 20%), and it virtually disappeared when supplementary iron intakes through the national iron supplementation program were considered. The risk of exceeding the tolerable upper level (TUL) of intake of iron remains low in the population when receiving fortification of 10 mg/d, but is much higher if they consume greater amounts of iron through supplements (range: 0-54%). This newly and transparently defined Indian EAR of iron should be used to evaluate, with precision, the benefits and risks of iron fortification and supplementation policies.