Niacin is the generic name for nicotinic acid and nicotinamide. Niacin is fairlystable in foods. It can withstand reasonable amounts of heat and acid and is not destroyed during food storage.
Functions.Niacin serves as a coenzyme in energy metabolism and con-sequently is essential to every body cell. In addition, niacin is essential for the prevention of pellagra. Pellagra is a disease characterized by sores on the skin and by diarrhea, anxiety, confusion, irritability, poor memory, dizziness, and untimely death if left untreated. Niacin, when used as a cholesterol-lowering agent, must be closely supervised by a physician because of possible adverse side effects such as liver damage and peptic ulcers.
Sources.The best sources of niacin are meats, poultry, and fish. Peanuts andother legumes are also good sources. Enriched breads and cereals also contain some. Milk and eggs do not provide niacin per se, but they are good sources of its precursor, tryptophan (an amino acid). Vegetables and fruits contain little niacin.
Requirements.Niacin is measured in as aniacin equivalent (NE).OneNE equals 1 mg of niacin or 60 mg of tryptophan. The general recommenda-tion is a daily intake of 14 mg/NE for adult women and 16 mg/NE for adult men. Because excessive amounts of niacin have caused flushing due to vascular dilation (expansion of blood vessels), self-prescribed doses of niacin concentrate should be discouraged. Other symptoms include gastrointestinal problems and itching. If excessive amounts of niacin are ingested, liver damage may result.
Deficiency.A deficiency of niacin is apt to appear if there is a deficiency ofriboflavin. Symptoms of niacin deficiency include weakness, anorexia, indiges-tion, anxiety, and irritability. In extreme cases, pellagra may occur.