Vitamin B3 (niacin, nicotinic acid, nicotinamide, niacinamide)

Vitamin B3 is also known as niacin, nicotinic acid, nicotinamide, niacinamide and antipellagra vitamin or PP factor. Niacin is a water-soluble vitamin whose derivatives such as NADH play essential roles in energy metabolism in the living cell. Niacin works closely with vitamin B1, vitamin B2, vitamin B6, pantothenic acid, and biotin to break the carbohydrates, fats, and proteins in food
down into energy. Vitamin B3 is essential in the metabolism of carbohydrates (to produce energy), fats, and proteins. It also aids in the production of hydrochloric acid, needed for proper digestion. Additionally, vitamin B3 facilitates the body's ability to eliminate toxins. The name niacin derives from nicotinic acid + in. When the properties of niacin were discovered, it was thought prudent to choose a common name other than nicotinic acid, for fear that it might be confused with nicotine, leading to the ideas that either smoking provided vitamins or that wholesome food contained a poison.

Niacin plays an important role in ridding the body of toxic and harmful chemicals. It also helps the body make various sex and stress-related hormones in the adrenal glands and other parts of the body. Vitamin B3 is essential for the activity of many enzymes in the body. Enzymes are special substances that speed up chemical reactions in the body. These enzymes are responsible for the production of energy in the body, the breakdown of dietary fats, the production of certain hormones and cholesterol, the processing of genetic material (DNA) and the growth and maturation of the cells in the body. Niacin is effective in improving circulation and reducing cholesterol levels in the blood. Niacin needs can be partially met by eating foods containing protein because the human body is able to convert tryptophan, an amino acid, into niacin. Niacin, via its metabolites, is involved in a wide range of biological processes, including the production of energy, the synthesis of fatty acids, cholesterol and steroids, signal transduction, the regulation of gene expression and the maintenance of genomic integrity. Nicotinic acid, in pharmacological doses, is used as an antihyperlipidemic agent. Niacinamide is used to treat osteoarthritis, rheumatoid arthritis, insomnia, migraine headaches, and insulin-dependent diabetes. Vitamin B3 (Niacin) increases good cholesterol (HDL) and lowers bad cholesterol (LDL). Niacin may enhance the effectiveness of some medications prescribed to lower cholesterol.

Vitamin B3 comes in two basic forms - niacin (also called nicotinic acid) and niacinamide (also called nicotinamide). A variation on niacin, called inositol hexaniacinate, is also available in supplements. Niacin can be found in nuts, dairy products, lean meats, poultry, fish, and eggs. Some niacin is also supplied by legumes and enriched breads and cereals. The best dietary sources of vitamin B3 are found in beets, brewer's yeast, beef liver, beef kidney, pork, turkey, chicken, veal, fish, salmon, swordfish, tuna, sunflower seeds, and peanuts. The body can synthesize niacin from the essential amino acid tryptophan, but the synthesis is extremely slow; 60 mg of tryptophan are required to make one milligram of niacin. For this reason, eating lots of tryptophan is not an adequate substitute for consuming niacin. As serotonin synthesis is reliant on tryptophan availability, inadequate dietary intake of vitamin B3 may also therefore lead to depression. The liver is the main storage area for this vitamin and absorption of vitamin B3 takes place in the intestines. Vitamin B3 is required by the body for digestive processes, activating enzymes which nourish the brain, regulating blood pressure and regulating cholesterol levels.
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