Absorption of iron from Western-type lunch and dinner meals.

The absorption of nonheme iron was measured from 20 lunch and dinner meals, in 187 subjects with varying iron status. The meals comprised both vegetarian meals and meals containing meat and fish. The extrinsic tag method was used to label the nonheme iron. All absorption figures were related to the absorption of a 3-mg reference dose of inorganic iron and all absorption figures were normalized to a 40% absorption from the reference dose, corresponding to subjects who are borderline iron deficient. Despite only a 3-fold variation in content of nonheme iron in the meals there was a 7-fold difference in absorption of nonheme iron (0.13 to 0.98 mg) and a 20-fold variation in percentage absorption (2.2 to 45%). The highest absorption (0.98 mg) was seen from a vegetarian meal with a high content of ascorbic acid. The relative role of meat/fish and ascorbic acid in stimulating the absorption of nonheme iron was studied by adding or subtracting single food components.