Vitamin B12 (known as cobalamin) is a water-soluble vitamin closely related to folic acid. Each relies on the other for the body to be able to use them. Vitamin B12 is essential for maintaining the protective cover around the nerves and promotes their growth, making it an essential vitamin to have on a daily basis during pregnancy and when breastfeeding.
Vitamin B12 is only available in meat and dairy foods, therefore women who do not eat these are at risk of vitamin B12 deficiency. Vitamin B12 absorption is also inhibited by the drug metformin (taken for type 2 diabetes and insulin resistance), making B12 levels unusually low. Babies born to mothers who are vitamin B12 deficient are at risk of spinal cord damage and possibly a severe inability to move well. If the mother is vitamin B12 deficient while breastfeeding, her baby can also exhibit limited movement. Your
paediatrician may prescribe vitamin B12 supplements to help reverse the majority of these signs, but there can be permanent learning and language delays.
Pregnant and breastfeeding women who have a vegan diet usually need to have a daily vitamin B12 supplement (about 4ug per day). However, there are now foods fortified with Vitamin B12 such as some brands of soymilk, yeast extracts, veggie burgers and some cereals. Babies also rely on obtaining adequate vitamin B12 from their mothers through breast milk when breastfeeding. Fortified foods and/or supplements need to continue during this time. Women who have problems absorbing vitamin B12 from their bowel, may require prescribed vitamin B12 injections every 3 months.
NOTE: Contrary to popular belief yeast, miso (soybean paste), mushrooms and sea algae (spirulina) do not contain active vitamin B12. They may be present in these foods in small amounts, but they are unable to be absorbed by the body.
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