Babies need nutrients during their growth and development, but the nutrients needed in each period are somewhat different. 1. Infancy: from birth to 1 year old for infancy, from 14 days after birth, daily supplementation of vitamin D400IU, can prevent rickets and other diseases, 6 months after the timely addition of iron-containing complementary foods, such as fish and egg yolk foods are rich in iron, can prevent iron deficiency anemia. 2. Early childhood: 1~3 years old is the early childhood, continue to supplement vitamin D until two years old, supplement iron and high quality protein moderate amount of fish, eggs, lean meat, etc., to develop good eating habits. 3. Preschool period: from the age of 3 weeks to 6-7 years old before entering elementary school for the preschool period, children should pay attention to calcium, to high-quality protein diet, such as milk, fish, shrimp, eggs, etc., to ensure balanced nutrition. 4. School-age: from the age of 6-7 years old before entering elementary school to puberty for the school-age period, pay attention to meat and vegetables, to ensure that the intake of high-quality protein, you can eat more calcium-rich foods such as milk, black fungus, sea cucumbers, shrimp, etc., and vitamin A supplement. 5. Adolescence: generally 10-18 years old, to strengthen the nutrition, rich in high-quality protein, trace elements, vitamins and other foods, such as milk, shrimp, nuts and so on. Pay attention to reasonable collocation, balanced nutrition, if there is discomfort, go to the hospital in time.