According to the U.S. Food and Drug Administration, phytohaemagglutinin is found in many types of beans, however, red kidney beans contain the highest levels of hemagglutinin. White kidney beans contain a third as much of the toxin while broad bean varieties contain only 10% as much hemagglutinin as red kidney beans. That's still plenty, however, since you only need to eat four or five undercooked red kidney beans to get sick.