If a breastfeeding woman has a very good quality of breast milk and a large amount of milk, which is equivalent to a higher nutritional content, it is relatively easy to lose weight from the human body combined with a less regular and more strenuous work and rest, because she has to take care of the child. About 60-70% of breastfeeding women will lose weight. If the quality of breast milk is not particularly good, the milk is thin, and the amount is relatively small plus the amount of food is very high, this situation will easily cause weight gain. If a breastfeeding woman’s weight loss is particularly serious within a short period of time, for example, if she loses 20-30 pounds a month or more, she should pay attention to checking her blood glucose and thyroid function indicators, as breastfeeding women’s work and rest schedules are disturbed during breastfeeding and are prone to autoimmune diseases such as hyperthyroidism.