Bioavailability of iron bis-glycinate chelate in water.

Iron amino acid chelate is being increasingly considered in programs for iron fortification of foods. The bioavailability of iron bis-glycinate chelate given in water was studied using a double-isotopic method in a group of 14 women. Iron absorption from aqueous solutions of 15 mg/L of elemental iron as either iron bis-glycine chelate or ferrous ascorbate was not significantly different (34.6% and 29.9% respectively). Standardized iron absorption of the iron bis-glycinate was 46.3% (standardized to 40% absorption of the reference dose). There was a significant correlations between (ln) iron absorption of iron bis-glycinate chelate with (ln) serum ferritin (r = -0.60, p < 0.03) and with (ln) iron absorption from ferrous ascorbate (r = 0.71, p < 0.006), suggesting that iron bis-glycinate chelate absorption is indeed regulated by the iron stores of the body.