13. Kidney Beans

Raw or undercooked kidney beans contain phytohaemagglutinin, a toxin that can cause severe food poisoning symptoms such as vomiting, stomach cramps, and diarrhea — sometimes just within a few hours.
Eating as few as 4 or 5 undercooked kidney beans can trigger toxicity. That’s why kidney beans should never be eaten raw or lightly cooked. Boiling the beans for at least 10 minutes neutralizes the toxin and makes them safe to eat.
The danger often lies in using slow cookers or pressure cookers without pre-boiling the beans. These appliances may not reach the temperature needed to destroy the toxin, making the beans even more dangerous.
Soaking kidney beans overnight and boiling them properly the next day is the best way to ensure their safety. Canned beans are already pre-cooked and are a safer option if convenience is your priority.