Kidney Beans: The Common Kitchen Ingredient That Could Poison You

Image: Andy Melton

Bowl of chili with sour cream and cheese

“Abstain from beans”
Plutarch (Ancient Greek Biographer and Author, 46-119)

Plutarch had a reason for saying this. Many beans contain toxins, but the most toxic of all is the common kidney bean. As we are coming up on the colder season meant for soups, chilis and stews, it is timely to remember what the poison in the bean is and how to detoxify it.

Image: Sanjay Acharya

Close-up of kidney beans

The culprit of this intestinal mayhem is the toxin Phytohaemagglutinin (Kidney Bean Lectin) found in quite a few beans, though kidney beans have the highest amount. For example, raw kidney beans contain between 20,000 and 70,000 hau (hemagglutinating units) while white ones contain a third of that and broad beans only contain 5-10% of the figure. The operative word here is ‘raw.’ Once they are cooked properly, they are detoxified.