noun \ˈnī-ə-sən\

: a type of natural substance (called a vitamin) that is found in certain foods and that helps your body to be healthy

Full Definition of NIACIN

:  an acid C6H5NO2 of the vitamin B complex found widely in animals and plants and used especially against pellagra; also :  nicotinamide —called also nicotinic acid

Origin of NIACIN

nicotinic acid + 1-in
First Known Use: 1942


noun \ˈnī-ə-sən\   (Medical Dictionary)

Medical Definition of NIACIN

: a crystalline acid C6H5NO2 that is a member of the vitamin B complex occurring usually in the form of a complex of niacinamide in various animal and plant parts (as blood, liver, yeast, bran, and legumes) and is effective in preventing and treating human pellagra and blacktongue of dogs—called also nicotinic acid


noun    (Concise Encyclopedia)

Water-soluble vitamin of the vitamin B complex, essential to growth and health in animals, including humans. It is found in the body only in combined form as a coenzyme, nicotinamide adenine dinucleotide (NAD), which is involved in the metabolism of carbohydrates and the oxidation of sugar derivatives and other substances. One of the most stable vitamins, it survives most cooking and most preserving processes. It is widely found in dietary sources, especially lean meat. Deficiency causes pellagra. It is used as a drug to reduce high cholesterol levels in the blood.

Variants of NIACIN

niacin or nicotinic acid or vitamin B3


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