Niacin is a water-soluble vitamin, also known as vitamin B-3. The term niacin refers to both nicotinic acid and nicotinamide, both of which are used by the body to form the coenzymes nicotine adenine dinucleotide (NAD) and nicotine adenine dinucleotide phospate (NADP).

As many as 200 enzymes require the niacin coenzymes, NAD and NADP. NAD functions most often in reactions involving the degradation (catabolism) of carbohydrates, fats, proteins, and alcohol to produce energy. NADP functions more often in biosynthetic (anabolic) reactions, such as in the synthesis of fatty acids and cholesterol.

Niacin is necessary for the release of energy from carbohydrates and for alcohol processing. Niacin also has role to play in the regulation of cholesterol in the blood.

References

Colletti RB, Neufeld EJ, Roff NK, et al. Niacin treatment of hypercholesterolemia in children. Pediatrics. 1993; 92:78-82.Dietary Reference Intakes for Thiamin, Riboflavin, Niacin, Vitamin B6, Folate, Vitamin B12, Pantothenic Acid, Biotin, and Choline. Washington, DC: National Academy Press; 1998.Elam MB, Hunninghake DB, Davis KB, et al. Effect of niacin on lipid and lipoprotein levels and glycemic control in patients with diabetes and peripheral arterial disease: The ADMIT Study: A randomized trial. JAMA. 2000; 284:1263-1270.Goldberg A, Alagona P Jr, Capuzzi DM, et al. Multiple-dose efficacy and safety of an extended-release form of niacin in the management of hyperlipidemia. Am J Cardiol. 2000; 85:1100-1105.