Short-term beta-carotene supplementation of lactating mothers consuming diets low in vitamin A

We have previously shown that beta-carotene supplementation of the diets of healthy U.S. mothers increases serum and milk beta-carotene concentrations . Building on these results, we investigated the possibility that beta-caro tene supplementation could enhance the vitamin A status of mothers and thei r nursing infants. Three 30-mg doses of beta-carotene were administered an 3 consecutive days to 44 lactating mothers who had vitamin-A-poor diets. Co ncentrations of maternal serum and milk carotenoids and retinol were evalua ted at baseline and after 2 and 3 days of supplementation. Infant serum car otenoids and retinol were measured at baseline and 2 days following materna l supplementation. beta-carotene supplementation markedly elevated maternal serum and milk beta-carotene concentrations (nine- and sevenfold, respecti vely) and resulted in smaller,transient increases of alpha-carotene, lycope ne, and beta-cryptoxanthin concentrations in maternal serum. Maternal serum and milk retinol were unchanged in response to the treatment. In contrast, maternal beta-carotene supplementation significantly increased infant seru m retinol (P less than or equal to 0.001) and beta-carotene concentrations remained unchanged. These results imply that breast milk beta-carotene can supply retinal for the nursing infant Further research is needed to identif y the site of bioconversion of milk-derived beta-carotene to retinol and to describe the factors that regulate this process. (J. Nutr. Biochem. 10:532 -538, 1999) (C) Elsevier Science Inc 1999. All rights reserved.