Infancy from 0-6 months is the first growth spurt in life, and the need for energy and nutrients is higher than any other period. However, the digestive and excretory organs of infants are not yet mature and functionally incomplete, and their ability to digest and absorb food and excrete metabolic waste is still low. Breast milk can provide high quality, comprehensive, adequate and structurally appropriate nutrients to meet the needs of growth and development, and it can perfectly adapt to the immature digestive ability of infants and promote their organ development and functional maturity. In addition, infants from 0 to 6 months of age need to complete the transition from intrauterine dependence on maternal nutrition to extrauterine dependence on food nutrition, and milk from the mother is the best food to complete this transition, based on any other food feeding methods can not be comparable to breastfeeding. Exclusive breastfeeding can meet all the liquid, energy and nutrient needs of infants up to 6 months of age. The nutrients and many bioactive substances in breast milk constitute a special biological system that provides all-round care for infants, helping them to adapt to the ecological environment of nature and grow up healthily even after leaving the protection of the mother’s womb. From 0 to 6 months of age, infants are in the second stage of the 1000-day window of opportunity, where nutrition, as the primary environmental factor, has a crucial impact on their growth, development and subsequent health. The appropriate amount of nutrition in breast milk provides infants with adequate and appropriate amounts of energy while avoiding overfeeding, allowing infants to achieve optimal and healthy growth rates and laying the foundation for a lifetime of health. Therefore, exclusive breastfeeding should be given to infants from 0 to 6 months of age. In view of the feeding needs and possible problems of infants from 0 to 6 months of age in China, based on the sufficient evidence available and with reference to the relevant recommendations of the World Health Organization (WHO), the United Nations Children’s Fund (UNICEF) and other international organizations, we propose guidelines for feeding infants from 0 to 6 months of age. 1. Open milk as early as possible after delivery and insist that the first food for newborns is breast milk Colostrum is rich in nutrients and immunologically active substances that help the development of intestinal function and provide immune protection. After delivery, the mother should start breastfeeding as soon as possible so that the baby can start sucking on the nipple to obtain colostrum and further stimulate lactation and increase milk secretion. The infant’s first food after birth should be breast milk to help prevent infant allergies and to reduce the incidence of neonatal jaundice, weight loss and hypoglycemia. In addition, allowing the infant to suckle the nipple repeatedly as early as possible is the key to ensure successful exclusive breastfeeding. When babies are born, they have certain energy reserves in their bodies to meet their metabolic needs for at least three days, so there is no need to worry about newborns’ hunger during the process of breastfeeding. Ancillary factors such as warm environment, pleasant mood, spiritual encouragement and breast massage can help smooth and successful initiation of breastfeeding. Preparation for breastfeeding should begin during pregnancy. 2. Insist on exclusive breastfeeding within 6 months of age Breast milk is the most ideal food for infants, and exclusive breastfeeding can meet all the fluids, energy and nutrients needed by infants within 6 months of age. In addition, breast milk is conducive to the establishment of a healthy intestinal micro-ecological environment and maturation of intestinal functions, reducing the risk of infectious diseases and allergies. Breastfeeding creates an environment of emotional communication between mother and child, giving infants the greatest sense of security and facilitating their psycho-behavioral and emotional development, and breastfed babies are the smartest. Breastfeeding is economical, safe and convenient, and helps to avoid maternal postpartum weight retention and reduces the risk of maternal breast cancer, ovarian cancer and type 2 diabetes. Exclusive breastfeeding should be adhered to for 6 months. Breastfeeding requires the efforts of the whole society, technical guidance from professionals, and active support from families, communities and workplaces. Make full use of policies and laws to protect breastfeeding. 3, compliant feeding, develop good habits Breastfeeding should be compliant with the maturation of the infant’s gastrointestinal tract and the growth and development process, from on-demand feeding pattern to regular feeding pattern progression. Infant hunger is the basis of on-demand feeding. Infants should be fed promptly when hunger causes crying, generally 6~8 times a day or more. Parents should clearly perceive the time information of their infants’ feeding pattern. As the age of the baby increases, the volume of the baby’s stomach gradually increases, the amount of milk intake increases, the feeding interval is extended, and the number of feedings decreases, gradually forming good eating habits with regular feeding. If the infant’s crying is obviously not in line with the usual feeding pattern, you should first rule out non-hunger causes, such as gastrointestinal discomfort. If the baby is crying for non-hunger reasons, increasing the number of feedings can only relieve the baby’s anxiety, but cannot solve the fundamental problem. 4, a few days after birth to start supplementing vitamin D, do not need to supplement calcium. The vitamin D content in human milk is low, and breastfed children do not get sufficient vitamin D through breast milk. suitable sunlight exposure will promote the synthesis of vitamin D in the skin, but given the limitations of parenting, sunlight exposure may not be the most convenient way for infants to get vitamin D within 6 months of age. Daily vitamin D supplementation of 10 μg (400 IU) should be initiated within days of birth. Exclusive breastfeeding can meet the infant’s calcium requirements for bone growth without additional calcium supplementation. Vitamin K supplementation is recommended for newborns after birth, especially for newborns born by cesarean section. 5.Infant formula is a helpless choice when exclusive breastfeeding is not possible. When infants cannot be fed with exclusive breast milk due to certain metabolic diseases, mothers suffering from certain infectious or mental diseases, insufficient milk secretion or no milk secretion, etc., it is recommended that formula feeding suitable for infants from 0 to 6 months of age is preferred, and it is not advisable to feed infants directly with ordinary liquid milk, adult milk powder, protein powder, soy milk powder, etc. No infant formula is comparable to breast milk, and should only be used as a reluctant alternative after exclusive breastfeeding has failed, or as a supplement to breast milk after 6 months of age. giving up breastfeeding before 6 months of age in favor of infant formula is detrimental to the health of the infant. No infant formula is comparable to breast milk and should only be used as a last resort after breastfeeding failure or as a supplement to breast milk when breast milk is insufficient. Formula is recommended for infants 0-6 months of age in the following cases: (1) Infants with galactosemia, phenylketonuria, or severe breast milk hyperbilirubinemia. (2) The mother has HIV and human T-lymphotropic virus infection, tuberculosis, varicella-zoster virus, herpes simplex virus, cytomegalovirus, hepatitis B and hepatitis C virus infection, as well as drug abuse, heavy consumption of alcoholic beverages and smoking, use of certain drugs, cancer treatment, and close exposure to radioactive materials. (3) Insufficient milk production despite professional guidance and various efforts. It is not advisable to feed infants from 0 to 6 months of age directly with ordinary liquid milk, adult milk powder, protein powder, soy milk powder, etc. 6. Monitor physical indicators to maintain healthy growth Body length and weight are visual indicators reflecting the feeding and nutritional status of infants. Infants should be measured for length and weight once every six months before 6 months of age, and the number of measurements can be increased during the recovery period after illness to ensure reasonable feeding. Infant growth has its own rules, too fast or too slow growth is not conducive to the long-term health of children. Infants have individual differences in growth and fluctuate in stages, so there is no need to compare growth indicators with each other. Breastfed children may have lower weight gain than formula-fed children, but as long as they are on a normal growth trajectory, they are in a healthy growth state.