There are two kinds of toxins in beans. One is phytohemagglutinin in beans. Its toxicity mainly lies in its combination with specific parts on the surface of small intestinal cells, which can have obvious adverse effects on the physiological functions of intestinal cells. The most serious thing is to damage gastrointestinal cells to absorb nutrients such as protein and sugar from the gastrointestinal tract, leading to nutritional deficiency, growth inhibition and even death in severe cases.

The other is saponin existing in pod (skin), whose toxicity is mainly reflected in hemolysis and sapogenin, which can strongly stimulate gastrointestinal mucosa. Causes local congestion, swelling and inflammation, leading to nausea, vomiting, abdominal pain and diarrhea.

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The People's Daily Food Channel reminds that beans that are not fully cooked at 80℃ are more toxic. Therefore, the best way for beans is to pinch off both ends and stew them with water to ensure that the water in the pot does not pass the beans. If both ends of beans are not removed or not completely cooked, it is easy to produce adverse reactions such as nausea, vomiting, diarrhea and dizziness after eating. Hong Zhongxin, chief physician of Nutrition Department of Beijing Friendship Hospital, suggested in an interview with Health News that heating lentils evenly to 100℃ and boiling them on low fire for 30 minutes can effectively destroy the toxic substances in them.

Baidu encyclopedia-beans

People's Network-Can you be poisoned by eating beans? Actually, it's because the beans are not fully cooked.