Effect of a micronutrient fortificant mixture and 2 amounts of calcium on iron and zinc absorption from a processed food supplement

Abstract

Background: Iron, zinc, and calcium can interact with each other in a way that inhibits their respective absorption. On the other hand, mineral fortification has been used to improve simultaneous iron and zinc absorption from food supplements.

Objective: We evaluated the effect of a novel fortificant mixture consisting of NaFeEDTA, zinc methionine, ascorbic acid, and citric acid on iron and zinc absorption from a dry food supplement designed for preschool children.

Design: The standard food supplement contained cereal and legume flour, dried milk, and a mixture of micronutrients including ferrous sulfate and zinc sulfate as sources of supplemental iron and zinc, respectively. Standard and novel food products were prepared as porridge with or without the addition of 200 mg Ca as calcium phosphate. Iron absorption and zinc absorption from the food products were evaluated simultaneously in 13 nonpregnant, adult women by extrinsically labeling the products with radioisotopes of iron and zinc and carrying out whole-body counting 7 d after the food products were consumed in random order.

Results: The absorption of iron from the NaFeEDTA-containing (novel) food product was 1.7 times that from the ferrous sulfate-containing (standard) product (P = 0.015). There was no significant effect of dietary calcium on iron absorption. Zinc absorption was not associated with the form of zinc consumed, but higher dietary calcium was marginally associated with lower zinc absorption (P = 0.071).

Conclusions: A mixture of fortificants containing NaFeEDTA, zinc sulfate or zinc methionine, ascorbic acid, and citric acid, but without calcium, can improve iron and zinc absorption from food products. A cost-benefit analysis of the novel fortificant mixture needs to be performed.