Inhibitory effect of oat products on non-haem iron absorption in man

Oat products are increasingly used in human nutrition due to the rather high content of soluble fibre. Oat products, however, have a high content of phytate which may interfere with the absorption of non-haem iron. The iron balance situation is critical in several groups, especially in children, teenagers and women in their fertile years. It is therefore important to examine the effect of oat products on non-haem iron absorption in man. The present studies showed that oat bran and oat porridge markedly inhibited the absorption of non-haem iron. The inhibition can be explained by the high phytate content of oat products. This is partly due to a high resistance of oat phytate against exogenous phytase and partly to an inactivation of the endogenous phytase in oats caused by the usual heat treatment of oats which is made to prevent rancidity of oat lipids during storage. The inhibitory effect of oat products on iron absorption is sufficiently marked to be a serious consideration if such products are more regularly consumed.