What is the recommended daily intake of vitamin D for infants?

The recommended daily intake of vitamin D for infants is 400 IU. This guideline is based on the need to support bone health and proper development, as vitamin D plays a crucial role in calcium absorption and metabolism. The American Academy of Pediatrics (AAP) recommends that infants, especially those who are exclusively breastfed or consuming less than 1 liter of vitamin D-fortified formula daily, receive a supplement of 400 IU per day starting in the first few days of life. This recommendation is aimed at preventing rickets and ensuring that infants achieve optimal growth and bone density.