Nutritional Biochemistry
Folate
Folate, also known as vitamin B9, is a water‑soluble B vitamin essential for one‑carbon metabolism, nucleotide biosynthesis, and remethylation of homocysteine. Naturally occurring in foods as polyglutamates and added to foods or supplements as folic acid, adequate folate status is critical for cell division and early embryonic neural tube closure and is a cornerstone of public health fortification and periconceptional supplementation policies.
Vitamin B12
Vitamin B12, or cobalamin, is a water‑soluble vitamin essential for neurologic function, red blood cell formation, and DNA synthesis. It is naturally present in animal-derived foods and certain fortified products, absorbed in the ileum via an intrinsic factor–mediated process, and functions as a cofactor for methionine synthase and methylmalonyl‑CoA mutase. Deficiency can cause megaloblastic anemia and neuropathy and is most common in older adults, people with malabsorption, and individuals following strict vegan diets.