In general, a small amount of intake of black beans will not have an effect on the human body. Some women may be due to black beans have certain beauty, hair growth and other effects, in the absence of professional guidance blindly long-term, a large number of black beans, may cause the following kinds of harm: 1, increase the burden on the kidneys: black beans are rich in protein, a large number of black beans will increase the burden on the kidneys, especially the kidney function is impaired patients, should avoid eating a large number of black beans; 2, cause elevated uric acid: black beans are rich in Purine, in the process of kidney metabolism may also produce purine, causing elevated uric acid; 3, increase the burden on the gastrointestinal tract: black beans are rich in dietary fiber, which helps promote gastrointestinal peristalsis and relieve constipation, but excessive consumption of black beans can increase the burden on the gastrointestinal tract, leading to indigestion, bloating and other phenomena; 4, affect the absorption of iodine: large amounts of black beans may also affect the absorption of iodine, resulting in thyroid insufficiency or enlargement; 5, Reduce protein absorption and utilization: The antitrypsin in black beans may also reduce the absorption and utilization of protein, while the hemagglutinin will inhibit growth. In addition, excessive consumption of black beans may also make women endocrine disorders, coagulation abnormalities, etc., so no matter what food you eat should be in moderation.