Effect of tea and other dietary factors on iron absorption.

Iron deficiency is a major world health problem, that is, to a great extent, caused by poor iron absorption from the diet. Several dietary factors can influence this absorption. Absorption enhancing factors are ascorbic acid and meat, fish and poultry; inhibiting factors are plant components in vegetables, tea and coffee (e.g., polyphenols, phytates), and calcium. After identifying these factors their individual impact on iron absorption is described. Specific attention was paid to the effects of tea on iron absorption. We propose a calculation model that predicts iron absorption from a meal. Using this model we calculated the iron absorption from daily menus with varying amounts of enhancers and inhibitors. From these calculations we conclude that the presence of sufficient amounts of iron absorption enhancers (ascorbic acid, meat, fish, poultry, as present in most industrialized countries) overcomes inhibition of iron absorption from even large amounts of tea. In individuals with low intakes of heme iro...