9 IRON BIOAVAILABILITY IN A COMMON CHILEAN DIET

Iron bioavailability of a diet is affected by several factors wich do not allow a prediction of the amount of iron absorbed. We studied the iron bioavailability of a common chilean diet. The diet contained 1750,6 cals, 2,3 mg heme-iron and 11,2 mg non heme-iron. Iron bioavailability was measured with an extrinsic tag. The study was done in 10 males and 20 females, all adults. Tag was incorporated in the bread. The first day each subject received breakfast with 4uCi of55Fe. The second day the same subject received lunch with 1,2uCi of59Fe. On day 15, a peripheral blood sample was obtained and the circulating radioactivity was determined by the Eakins and Brown method. On the same 15th day, the subject received dinner containing 1,2uCi of59Fe and on day 16 an aqueous solution of ferrous ascorbate tagged with 4uCi of 55Fe. On day 30 the increase in circulating radioactivity was measured. The geometric means of iron absorption were 1,85% for breakfast, 3,98% for lunch, 1,79% for dinner and 23,25% for the reference solution. As per Layrisse, the amount of heme iron absorbed was 0,465 mg and the non heme 0,277 mg, wich are less than allowances. We will comment these results in the context of iron deficiency prevalence in Chile.