First, choose fruits with less sugar. According to research, pineapple, honeydew melon, papaya, kiwi fruit, banana, grape and other fruits have high glycemic index, so dieters should avoid eating too much of these fruits. However, apples, kiwis, lemons, plums, cherries and oranges have low glycemic index, which is a good choice for dieters with fruit meals. Secondly, it is best to eat fruit before meals. Studies have shown that if you eat some fruits or drink 1-2 cups of juice 20-40 minutes before meals, you can prevent obesity caused by overeating. Because fruit or juice is rich in fructose and glucose, it can be quickly absorbed by the human body, so that the blood sugar concentration increases and the appetite decreases. The crude fiber in fruit can also make the stomach feel full. In addition, eating fruit before meals can significantly reduce the demand for fatty foods, thus indirectly preventing the adverse consequences of excessive fat accumulation in the body. But many fruits, such as persimmons, hawthorn, almonds and pineapples, can't be eaten on an empty stomach. In order to lose weight, when eating fruits before meals, it is best to choose fruits that are not too sour and astringent, such as apples, pears, bananas, grapes, watermelons and melons. It is difficult to lose weight after eating fruit. Because eating fruit after a meal is equivalent to eating more sugar, which is easy to be converted into fat and stored in the body, and may also gain weight. Especially don't eat a lot of fruit after dinner, because synthetic fat is most likely to accumulate in the body after eating at night. But some fruits can promote digestion, such as pineapple and kiwi fruit rich in protease, lemon and hawthorn rich in organic acids. For this kind of fruit, you can eat it about an hour after meals. Third, don't eat too much fruit. Most people think that fruits are rich in cellulose, almost free of fat and protein, and can be eaten without restraint. Actually, this is a misunderstanding. Fruit is not a low-energy food. Because it tastes sweet and easy to eat more, the sugar in it will be converted into fat and piled up. For example, every100g strawberry has about 30 calories. If you like strawberries and can eat a lot at a time, the calories you consume are amazing. For example, if you eat half a medium-sized watermelon (the pulp weighs about 2 kilograms), you will unconsciously consume 680 calories, which is equivalent to about three bowls of rice. Therefore, when eating fruit diet meals, we should control the consumption of fruit. As long as the method is proper, fruit weight loss will have great effect. However, fruit can't replace staple food, or even dinner. Because fruit has no nutrition after all, if you use fruit instead of dinner for a long time, it will also affect your health.