Role of gastric secretion in iron absorption.

The availability of inorganic iron for absorption in the small intestine is largely dependent on its physical and chemical state when it reaches the point of entry into the epithelial cells of the jejunum. This state is influenced by intraluminal factors both in the stomach and the upper intestine. Iron absorption can be increased in achlorhydric subjects by the administration of hydrochloric acid (Jacobs, Both-well, and Charlton, 1964) and in anaemic patients iron absorption is correlated with the amount of intrinsic acid secretion (Jacobs, Rhodes, Peters, Campbell, and Eakins, 1966). Ferric ions normally undergo polymerization followed by precipitation when acid solutions are brought to neutrality and ferrous ions in similar conditions tend to be oxidized