Question: What causes Gallstones ?
Answer: Imbalances in the substances that make up bile cause gallstones. Gallstones may form if bile contains too much cholesterol, too much bilirubin, or not enough bile salts. Scientists do not fully understand why these imbalances occur. Gallstones also may form if the gallbladder does not empty completely or often enough. The two types of gallstones are cholesterol and pigment stones: - Cholesterol stones, usually yellow-green in color, consist primarily of hardened cholesterol. In the United States, more than 80 percent of gallstones are cholesterol stones.1 - Pigment stones, dark in color, are made of bilirubin.
Source: NIDDK

Question: What to do for Gallstones ?
Answer: Factors related to eating, diet, and nutrition that increase the risk of gallstones include - obesity - rapid weight loss - diets high in calories and refi ned carbohydrates and low in fi ber People can decrease their risk of gallstones by maintaining a healthy weight through proper diet and nutrition. Ursodiol can help prevent gallstones in people who rapidly lose weight through low-calorie diets or bariatric surgery. People should talk with their health care provider or dietitian about what diet is right for them.
Source: NIDDK