Vitamin B6

Vitamin B6 is a water-soluble vitamin that is naturally present in many foods, added to others, and available as a dietary supplement. It serves as a coenzyme for more than 100 enzymes involved in metabolism, primarily protein metabolism, but also carbohydrate and fat metabolism. It also plays a role in cognitive development through the biosynthesis of neurotransmitters, and in the maintenance of normal homocysteine levels, a factor in cardiovascular health. The term 'Vitamin B6' refers to six related compounds: pyridoxine (an alcohol), pyridoxal (an aldehyde), and pyridoxamine (a nitrogen-containing group), and their phosphorylated forms pyridoxine 5'-phosphate, pyridoxal 5'-phosphate (PLP), and pyridoxamine 5'-phosphate. PLP is the active form of the vitamin and is the coenzyme for many metabolic reactions. The body converts all other forms of Vitamin B6 into PLP. Good dietary sources of Vitamin B6 include poultry, fish, organ meats like beef liver, potatoes, and non-citrus fruits. Fortified cereals also contribute to dietary intake. Deficiency is uncommon in healthy individuals but can occur in those with impaired renal function, autoimmune diseases, chronic alcohol dependence, or malabsorption syndromes (NIH ODS).