ABSTRACT
The B vitamins provide cofactors or prosthetic groups to various enzymatic reactions. Among the B vitamins, vitamin B6 is important in that it is involved in the metabolism of all three macronutrients, proteins, lipids, and carbohydrates. The enzymes involved in the metabolism of amino acids use pyridoxal phosphate as the cofactor. Because of the extensive nature of these reactions, the requirement of this vitamin is related to the protein content of the diet. Through the amino acid decarboxylase reactions that generate monoamine neurotransmitters, vitamin B6 is intimately associated with the function of the nervous system. It also has an obligatory role in immune and endocrine systems. This chapter attempts to review the biological role of vitamin B6 in health and in disease.
