It is not true that women’s body metabolism will be accelerated during menstruation, but the speed of metabolism is only about 30% of the usual rate, so eating high-calorie food or food with high fat content will still have the possibility of gaining weight. If a woman feels that she has eaten more after menstruation but has not become obese, she may be heavier before menstruation due to increased hormone levels, sodium and water retention in the body, and pelvic edema and congestion, but after menstruation, the water in the body is metabolized and the menstrual blood is discharged, so the weight measured is lighter. This situation is due to the metabolites discharged to compensate for the weight gain after eating, so it is not valid to eat during menstruation without gaining weight. Women who need to control their weight can reasonably adjust their eating habits and increase exercise to reduce the amount of body fat.