Did You Know Raw Beans are Poisonous?
Beans are a popular food, being protein rich, and full of good fiber and chronic disease fighting antioxidants. Here in the USA, health experts are encouraging us to include more and more beans in our diet.
But are you aware that there is a danger to consuming beans which is more serious than the embarrassing “toot! toot!” often produced by this “musical fruit”? Did you know that raw beans contain a toxin, which in some varieties may reach dangerous levels? Did you know that under cooking beans may actually INCREASE their toxicity?
The toxin found in beans is phytohemagglutinin (PHA), which is a type of protein called a “lectin”. Lectins can be very dangerous indeed: the nasty poison ricin is a lectin. But before you begin to throw away all your beans, rest assured that ricin is NOT derived from them, but rather a different, totally unrelated plant.
Amongst the beans, uncooked red kidney beans have the highest concentration of PHA. Apparently as few as five raw red kidney beans need to be eaten to cause symptoms of poisoning to appear. White kidney beans also have high concentrations of PHA, so any “kidney” shaped bean needs to be cooked properly before being eaten.
Proper cooking means boiling for at least 10 minutes.
Oddly enough, cooking beans at lower temperatures, (such as in a slow cooker), may actually INCREASE either the level or potency of PHA, so be sure you cook your beans at hot enough temperatures. It goes without saying that you should never use kidney bean sprouts raw in a salad, and most authors state that stir-frying kidney bean sprouts does NOT make them safe to eat. So don’t use kidney bean sprouts!!
Beans are a valuable addition to our diet, but like most foods, we need to ensure we prepare them properly.
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