Toxicity of Red Kidney Beans (Phaseolus vulgaris) in the Rat

Abstract

A series of experiments was conducted to obtain information on the etiology of “kidney bean toxicosis.” Some of the deaths observed among weanling rats fed high levels of raw kidney beans were attributed to hypoglycemia. Low blood glucose values and brain lesions comparable to those of hypoglycemia as reported from other causes were observed in rats fed diets containing 74% kidney beans. It is suggested the hypoglycemia resulted because raw beans contain factors such as hemagglutinin and trypsin inhibitor that decrease feed intake and feed utilization. Force-feeding of diets containing raw beans to increase intake increased survival time over that of rats fed the diets ad libitum. Limiting the intake of rats fed a control diet to that consumed by rats fed 74% bean diet resulted in low blood glucose values in the control animals. Older rats survived longer than young rats when fed diets containing 74% beans. Autoclaving or soaking the beans in water for 72 hours eliminated the toxic effect.