The main reasons for exhaust after eating black beans are: 1. black beans contain a large amount of protein, the process of digestion in the gastrointestinal tract will produce a lot of nitrogen and carbon dioxide, smells bad, the phenomenon of exhaust odor. 2. black beans contain a large number of B vitamins and dietary fiber, in addition to the digestive process in the gastrointestinal tract to produce a large amount of gas, can stimulate intestinal peristalsis, the intestinal waste gas out of the body. 3. 3, black beans contain a lot of saponin, if black beans are not fully cooked, the saponin on the gastrointestinal tract will produce stimulation, resulting in increased intestinal peristalsis, serious cases can lead to damage to the gastrointestinal mucosa, gastric mucosa damage can occur after acute enteritis, which appears exhaust odor.