Abstract

Vitamin D-deficiency rickets continues to be reported in infants fed human milk, and the importance of human milk as a source of vitamin D for infants is controversial. Furthermore, effects of race and of normally consumed maternal vitamin D intake on human-milk vitamin D have not been reported. Milk, serum, and three-day-diet diaries were obtained from 25 mother-infant pairs. Human-milk vitamins D3 and D2 and 25-hydroxyvitamin D3 were lower in blacks vs whites, whereas 25-hydroxyvitamin D2 did not differ. Total-milk vitamin D, but not 25-hydroxyvitamin D, correlated with vitamin D intake. Milk vitamin D2 specifically was correlated with vitamin D intake even after controlling for race. Infant serum 25-hydroxyvitamin D did not correlate with milk vitamin D or 25-hydroxyvitamin D; we speculate that the contribution of vitamin D from human milk in these infants is insignificant relative to the contribution from sunshine exposure.