Sodium iron EDTA [NaFe(III)EDTA] as a food fortificant: The effect on the absorption and retention of zinc and calcium in women

The iron fortificant NaFeEDTA could have a potential negative effect on the metabolism of other minerals. We have used stable isotopes to monitor zinc and calcium metabolism in 10 women consuming a single meal of high- extraction wheat rolls (100 g flour) fortified with 5 mg Fe as either FeSO₄ or NaFeEDTA. Six-day chemical balances were made simultaneously to study apparent zinc and calcium retention from the complete diet containing the differently iron-fortified breads (200 g flour; 10 mg added Fe/d). Mean ⁷⁰Zn absorption from the bread meal increased from 20.9% with FeSO₄ to 33.5% with NaFeEDTA (P < 0.05) whereas mean ¹⁴Ca absorption was 53.3% from both breads. When NaFeEDTA-fortified bread was consumed, there was a small but significant increase in urinary excretion of ⁷⁰Zn and ⁴⁴Ca. There was a similar small increase in urinary zinc excretion during the 6-d balance, although the apparent retention of zinc and calcium was not different. Thus, we found no negative overall effect of NaFeEDTA consumption on the metabolism of zinc and calcium. In contrast, the result suggest that NaFeEDTA added to low-bioavailability diets might increase zinc absorption as well as provide iron with high bioavailability.