Discovery

Nicotinic acid was first discovered from the oxidation of nicotine. When the properties of nicotinic acid were discovered, it was thought prudent to choose a name to dissociate it from nicotine and to avoid the idea that either smoking provided vitamins or that wholesome food contained a poison. The resulting name 'niacin' was derived from nicotinic acid + vitamin. Vitamin B3 is also referred to as "vitamin PP", a name derived from the obsolete term "pellagra-preventing factor."

Industrial use

Nicotinic acid reacts with hemoglobin and myoglobin in meat to form a brightly coloured complex, and thus has been used as a food additive, typically to improve the colour of minced (ground) meat. Niacin is licensed as a food colouring agent in some, non-European, countries.

Bioavailability

The liver can synthesize niacin from the essential amino acid tryptophan (see below), but the synthesis is extremely slow and requires vitamin B6; 60 mg of tryptophan are required to make one milligram of niacin. Bacteria in the gut may also perform the conversion but are inefficient. For this reason, eating lots of tryptophan is not an adequate substitute for consuming niacin. However, this explains why pellagra requires a deficiency of protein as well as niacin.

Other uses

Biosynthesis

The 5-membered aromatic heterocycle of the essential amino acid, tryptophan, is cleaved and rearranged with the alpha amino group of tryptophan into the 6-membered aromatic heterocycle of niacin. By the following reaction:

Food Sources

• liver, heart and kidney
• chicken
• fish: tuna, salmon
• milk
• eggs

Fruits and vegetables:

• Northwestern University Nutrition
• Jane Higdon, "Niacin", Micronutrient Information Center, Linus Pauling Institute
• Postgraduate Medicine

Bibliography

• Parsons, William B.. Cholesterol Control Without Diet! The Niacin Solution. Lilac Press; 2nd edition, updated 2003, Buena Vista, CO. ISBN 0-9662568-7-5.
• Kowalski, Robert E.. The New 8-Week Cholesterol Cure : The Ultimate Program for Preventing Heart Disease. HarperCollins; 1st Quill edition 2003, New York, NY. ISBN 0-06-103176-3.
• Hoffer A (1962). Niacin therapy in psychiatry (American lecture series). Thomas. ASIN B0007E5ZNQ.
• Hoffer A (1992 (1966, 1978)). How to Live With Schizophrenia, 2nd ed., revised, Citadel Press. ISBN 0-8065-1382-9.
• Hoffer A (1966). New Hope for Alcoholics. University Books.
• Hoffer A; Pauling L (2004). Healing Cancer: Complementary Vitamin & Drug Treatments. CCNM Press. ISBN 1-897025-11-4.