Studies about vitamin D and breastfeeding:
Conclusion: Vitamin D-deficient mothers have vitamin d-deficient breast milk, putting their newborns at a high risk of vitamin D deficiency.
Vitamin D Requirements During Lactation: High-Dose Maternal Supplementation as Therapy to Prevent Hypovitaminosis D for Both the Mother and the Nursing Infant (2004)
Conclusion: This randomized control trial found that breastfeeding mothers need at least 4,000 IU of vitamin D daily to ensure their breastfeeding infants are getting enough vitamin D.
Conclusion: Infants who are being breastfed by vitamin D-deficient mothers and not getting any supplementary vitamin D are guaranteed to develop an even worse vitamin D-deficiency than their mothers. Severe vitamin D-deficiency in young children can cause seizures, rickets, autoimmune disorders, mental disorders, and stunted physical and mental development. It is crucially important for lactating mothers to have optimal vitamin D levels.
Conclusion: 30 cases of infant and childhood nutritional rickets in North Carolina were analyzed. 100% of the patients were dark-skinned, had been breast-fed an average of 12 months, and did not receive vitamin D supplements prior to their rickets diagnoses. Dark-skinned people tend to have disproportionately lower vitamin D levels due to the melanin in their skin blocking UVB solar radiation necessary for vitamin D synthesis. Babies who are breastfed by vitamin D-deficient mothers without receiving vitamin D supplements tend to develop even more severe vitamin D deficiencies than their mothers.
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