There are contraindications to the use of cosmetics during breastfeeding, and the harmful substances of some cosmetics can be absorbed by the mother’s skin and then enter the baby’s body through breast milk, or jeopardize the health of the baby through direct skin contact between the mother and the baby. 1. Breastfeeding is an important stage in the growth and development of infants, and breast milk can affect the health of infants. Cosmetics contain many chemicals that can be absorbed into breast milk through mom’s skin and harm the baby’s health. Therefore, mothers should avoid using some items that affect the safety of breast milk. 2. Some cosmetics contain ingredients that are not safe for babies, such as salicylic acid, vitamin A, fruit acids, etc. Some cosmetics even contain lead, mercury and other heavy metals, which are not conducive to healthy growth when absorbed by babies. It should be noted that if you need to use cosmetics, you should buy them from regular channels and try to choose cosmetics that are not harmful to babies. In addition, during the breastfeeding period, mothers should avoid smoking, stay away from second-hand smoke, pay attention to balanced nutrition and eat a light diet. If the mother and the baby are not feeling well, they should seek medical advice promptly.