Vitamin D Supplementation Guidelines for Infants

Introduction to Vitamin D Supplementation

The American Academy of Pediatrics recommends vitamin D supplementation at 400 IU daily for breastfed infants throughout the entire breastfeeding period, and for formula-fed infants until they consistently consume at least 28 ounces of vitamin D-fortified formula per day 1, 2

Breastfed infants should begin 400 IU daily vitamin D supplementation at hospital discharge and continue throughout the entire duration of breastfeeding, regardless of whether breastfeeding is exclusive or partial, as breast milk contains insufficient vitamin D to meet infant requirements 1, 2, 3
There is no specified upper age limit for discontinuation of vitamin D supplementation in breastfed infants—the key determinant is continuation of breastfeeding, not the infant's age 1

Formula-fed infants should continue 400 IU daily vitamin D supplementation until they reliably consume at least 28 ounces of vitamin D-fortified formula per day 2, 3
Once the 28-ounce threshold is consistently met, supplementation can be discontinued as the formula provides adequate vitamin D 2

Preterm infants require 200-1,000 IU/day (or 80-400 IU/kg/day) of vitamin D supplementation along with multivitamin preparations, and should continue supplementation until consuming a completely mixed diet with normalized growth and hematologic status 1, 4
Infants on long-term parenteral nutrition require periodic monitoring for vitamin D deficiency, with a target 25(OH)D level >50 nmol/L or 20 ng/mL, and additional supplementation is needed if levels fall below target 1, 5

Lactating mothers can take 6,400 IU daily instead of direct infant supplementation, providing adequate vitamin D through breast milk, and this approach should continue throughout the breastfeeding period 1, 2, 3

Supplementation should not be discontinued at an arbitrary age, but rather based on feeding method and volume, to ensure adequate vitamin D levels in infants 1, 2