Effect of vitamin A deficiency on iron bioavailability

Vitamin A deficiency alters iron status leading to an iron overload in tissues; however, the mechanism of this interaction is poorly understood. The present study aimed to assess the effect of vitamin A deficiency on iron bioavailability and utilization in rats.

Animals were divided into three groups of six rats each that were fed AIN-93G diet (control group), a vitamin A deficient diet and an iron and vitamin A deficient diet, respectively, for 57 days. The concentrations of hepatic and splenic iron, haemoglobin, red and white cells as well as iron utilization and its bioavailability were evaluated in the three groups.

Vitamin A deficiency increased the concentration of red blood cells, haemoglobin concentration (Hb), and splenic iron as well as iron utilization. However, the iron bioavailability observed in vitamin A deficient rats was not significantly different compared to the control group, while in the iron/vitamin A deficient rats, it was higher (p = 0.0056). With regard to iron absorption, no difference was observed among the three groups.

Increase of haemoglobin, red blood cells and splenic iron concentration observed in vitamin A deficiency suggests that vitamin A may affect the iron mobilization from tissues rather than iron absorption.