Watermelon has a better taste and is loved by people. About 90% of watermelon is water, and the sugar content is 5%-12%, which is equivalent to 5-12 grams of sugar per 100 grams of watermelon, and the sugar content of watermelon is relatively high among fruits. Watermelon mainly includes vitamin A, phosphorus, potassium and other nutritional elements, does not contain fat and cholesterol, per 100 grams of calories is about 25 calories, calories are not particularly high, moderate consumption can help replenish human nutrition, a strong sense of satiety. As watermelon contains a lot of water, so eat watermelon for diuretic, anti-constipation can play a role. The sweet taste of watermelon is due to the glucose, fructose and sucrose contained in watermelon, which are more easily absorbed into the body and have a higher glycemic index. Therefore, it is recommended that diabetic patients with well-controlled blood sugar can consume small amounts at appropriate times under the guidance of a doctor, such as eating some watermelon between meals as appropriate. Watermelon is one of the ideal summer fruits, chilled taste will be more sweet, but chilled watermelon immediately, may lead to some people produce abdominal distension, abdominal pain and other gastrointestinal reactions, serious cases may even cause shock, so chilled watermelon should be taken out of the refrigerator and then placed for a period of time before consumption.