One serving of legumes (3/4 cup) has been shown to lower LDL or "bad" cholesterol levels by 5 percent, according to a meta-analysis of 26 trials published in the Canadian Medical Association. One cup of legumes contains 14 to 20 grams of fiber.
Studies have also shown that a person who eats more legumes has a lower risk of heart disease because of the soluble fiber, which can lower cholesterol and triglyceride levels. Legumes also contain cancer-fighting plant chemicals called isoflavones and phytosterols that have been associated with a reduced risk of cancer. Beans also provide a slow, steady source of glucose, as well as a balance of protein and complex carbohydrates that make them ideal additions for a diabetes sufferer's diet.
Because they are metabolized more slowly than other complex carbohydrates, beans may aid in weight loss by helping those who consume them feel full more quickly. Beans also contain a number of different nutrients, including antioxidants and vitamins and minerals such as folate, iron, manganese, magnesium, zinc, potassium and copper. Legumes are also an excellent source of protein, with a 1/2 cup of beans providing 7 grams of protein. They are also low in fat; most beans are only about 2 to 3 percent fat and contain no cholesterol.