Effects of vegetable proteins on iron and zinc absorption and availability in humans

Abstract

AbstractsThis review discusses research on the effects of vegetable protein diets on iron and zinc absorption and availability. Constituents of vegetables can have either a positive or negative effect on iron absorption. Although the use of soy protein to extend beef patties was found to decrease nonheme iron absorption in some studies, the use of soy‐extended beef on a regular basis was not found to deleteriously affect the iron status (serum ferritin levels) of adult men, menstruating females or school age subjects. Factors such as phytic acid level, dietary fiber content or protein source of vegetable protein diets have been implicated in decreasing the utilization of iron and zinc by humans. The effect of the molar ratio of phytate on the zinc of the diet is controversial: some studies find a decrease in zinc absorption with an increase in the phytate to zinc molar ratio; other studies find zinc absorption more dependent on the total amount of zinc in the meal than on the presence of phytic acid. Since many people meet their energy and protein requirements from vegetable sources, attention should be given to the mineral availability of these diets.