EXCERPTED FROM: Vitamin and Mineral Safety 3rd Edition (2013) Council for Responsible Nutrition (CRN) www.crnusa.org

Niacin: Nicotinic Acid, Nicotinamide, and Inositol Hexanicotinate Introduction Niacin is the vitamin B3 and has fundamental roles as part of reduction/oxidation coenzymes involved in energy metabolism, amino acid metabolism, and detoxification reactions for drugs and other substances. Niacin comes from in several forms: (1) nicotinic acid (pyridine-3carboxylic acid) (Burgeois et al. 2006), (2) nicotinamide (nicotinic acid amide), and (3) other derivatives (e.g., inositol hexanicotinate) “that exhibit the biological activity of nicotinamide” (Institute of Medicine [IOM] 1998). Other derivatives may be converted to nicotinic acid or may contain nicotinic acid, nicotinamide, or their releasable moieties; whether these compounds should be referred to as niacin depends on the biological effects that are attributed to them, the interpretation of the evidence for the rates of uptake and metabolism, and the release of the chemical components (apparent bioavailability) that produce biological effects similar to the primary forms of niacin.