Compared with other fruits, grapefruit belongs to citrus (eating more citrus can control weight), rich in vitamin C and fiber, and easy to feel full. However, grapefruit is very low in calories, comparable to watermelon. For example, a 20-calorie Shatian pomelo (140g). Grapefruit is rich in fruit acid, which can effectively stimulate gastrointestinal mucosa, affect the absorption of nutrients, and thus inhibit appetite, so it plays an outstanding role in weight loss. It also contains extra amino acids, which can inhibit insulin secretion. Thereby inhibit that conversion of blood sugar into fat in the liver. Grapefruit is a low GI food, so even if you eat a little more, its calories are only quickly converted into fat.