The Significance of Iron Turnover in the Control of Iron Absorption.

\Vitli the technical assistance of Arthur L. Foy T lIE STIMULUS to gastrointestinal absorption of iron remains unknown. Previous work seems to indicate that hepatic iron and total body iron stores are not as important as the rate of iron utilization in regulating iron absorption.’ Stimulation of erythropoiesis by blood letting increases iron utilization. However, following acute phlebotomy there is a 4to 5-day delay before iron absorption is increased.23 The present study was undertaken to delineate the plasma iron kinetics and intestinal iron content during this critical 5-day period in order to further our understanding of the regulation of intestinal absorption of iron.