Zinc absorption in infants fed iron-fortified weaning food.

The effect of fortification iron (reduced iron) on zinc absorption from a commercial vegetable-based weaning food was assessed in 11 9-mo-old infants. Each infant was fed a test meal of unfortified or iron-fortified product, labeled extrinsically with 1 mg 67Zn or 70Zn (as citrate), and the next day was fed the second product labeled with the other isotope. A complete fecal collection was carried out for 3-4 d, and the amount of unabsorbed isotope measured by thermal-ionization quadrupole mass spectrometry. Apparent zinc absorption (isotope intake minus fecal excretion, expressed as the % of dose administered) was 31.1 +/- 8.3% (x +/- SD) from the iron-fortified food and 28.6%28.6 +/- 10.5% from the unfortified food. These values were not significantly different, thus iron fortification of the weaning food did not reduce zinc absorption.