Very Low Human Milk Vitamin D in Breastfeeding Mothers in an environment with abundant Sunlight

IntroductionTheoretically, low human milk vitamin D (vD) could contribute to vD deficiency in breastfeeding infants who lack sunlight exposure and vD supplementation. Although human milk vD concentration seems affected largely by maternal skin exposure to UV light and dietary vD, an assessment of association of both risk factors with human milk vD concentration is very scarce. We evaluated the relationship among maternal vD intake, natural skin sun exposure, serum 25(OH)D, and human milk vD in a population where vD deficiency and rickets in infants are very common. We hypothesized that human milk vD concentrations will be very low in conservatively dressed Arab breastfeeding mothers because of restricted sunlight exposure and inadequate vD intake. MethodsWe measured milk vD in a convenience sample of 59 consecutive Arab breastfeeding mothers in Qatar prior to enrollment in a randomized controlled trial of high-dose vD supplementation to study prevention of vD deficiency in mothers and infants. All samples...