The inhibitory effect of dietary calcium on iron bioavailability: a cause for concern?

Increased intake of calcium has been recently recommended by a National Institutes of Health (NIH) Consensus Development Panel on Optimal Calcium Intake. However, high intakes of dietary calcium can inhibit iron absorption if both are present in the same meal. The mechanism for the calcium-iron interaction is not known. A recent study has demonstrated that separating foods high in calcium from meals high in iron can prevent some of the calcium-induced inhibition of iron absorption. The feasibility of changing the nature of meals or the timing of calcium supplementation to adjust for this phenomenon is untested.