Evidence and mechanism for pectin-reduced intestinal inorganic iron absorption in idiopathic hemochromatosis

The intestinal absorption of iron was measured in 13 patients suffering from idiopathic hemochromatosis by using a double radiotracer technique. For each patient, iron absorption was determined in the fasting state, i.e., under basal conditions, and after an oral indigestible fiber load (9 g/m2 of body surface) with either pectin (group I: eight patients) or cellulose (group II: five patients). The results were compared with those from a group of seven normal control subjects investigated under basal conditions. The patients with haemochromatosis (groups I and II) had a significant increase in the basal value of fractional iron absorption as compared with controls. In the patients of group I, the pectin induced a significant fall in fractional iron absorption (P < 0.02). In group II, iron absorption rates remained unchanged whether or not cellulose was given. Furthermore, we found in vitro that pectin had a high iron binding activity, while cellulose bound none. From the present study, we conclude that pectin but not cellulose reduces iron absorption by forming unabsorbable complexes with dietary iron. Thus, enrichment of the diet with foods providing significant amounts of noncellulosic dietary fibers, such as pectin, may be useful in the management of hemochromatosis patients.