100 calories of watermelon has about 400g grams. The calorie of watermelon is not high, the average calorie per 100 grams of watermelon is 26 kcal, therefore, according to this value, 100 calories of watermelon has about 400g grams, obese people will not gain weight if they eat in moderation. In addition, each 100 grams of watermelon contains 5.8 grams of carbohydrates, 0.1 grams of fat, 0.6 grams of protein, 0.3 grams of dietary fiber, 75 micrograms of vitamin A, 87 milligrams of potassium, 8 milligrams of calcium. It can also provide the body with energy as well as nutrients needed by the body to maintain the normal physiological function of the organism. However, it is not recommended to eat too much watermelon at one time, in order to prevent a large amount of consumption of gastrointestinal stimulation, causing diarrhea, abdominal pain and other conditions, resulting in gastrointestinal discomfort. Diabetic patients can moderate intake of watermelon, but should not be consumed in large quantities. Watermelon can also be consumed together with other vegetables and fruits, which is conducive to replenishing various nutrients for the human body and ensuring a balanced diet.