Weight gain during menstruation is due to changes in hormone levels in the body during menstruation, especially luteinizing hormone, and the retention of water and sodium in the body during this period, resulting in edema. Sometimes during menstruation, weight may increase by about 2-4 kg, and this increase may cause discomfort, fatigue, tiredness, and even breast tenderness, which are physiological changes. These uncomfortable symptoms will slowly disappear after menstruation, and the weight will return to the original weight, so there is no need to worry too much. During the menstrual period, you should pay attention to keeping warm, eat a light diet, try to eat less salty food, forbid cold, spicy and stimulating food, pay attention to rest and reduce strain.