Niacin, also known as vitamin B3, the third water-soluble vitamin discovered. Niacin is the generic term for nicotinic acid (pyridine 3-carboxylic acid) and nicotinamide (nicotinic acid amide). Both are used to form the coenzymes nicotinamide adenine dinucleotide (NAD) and nicotinamide adenine dinucleotide phosphate (NADP) which play essential roles for the development and function of living cells in human body.
Niacin is found naturally in many foods, and is added to some foods.
• Poultry, beef, pork, anchovies and fish
• Some types of peanuts, nuts, legumes, and grains
• Enriched and fortified foods, such as many breads and cereals
• Whole grains and whole meal wheat flour
In general, food rich in protein, with the exception of tryptophan-poor grains (e.g., corn, wheat), can satisfy some of the requirement for niacin. Important food sources of tryptophan are meat, milk and eggs.
The amino acid tryptophan contributes as much as two thirds of the niacin activity required by adults in typical diets.
Peanut butter is an excellent source of niacin. Fruits and vegetables provide useful amounts, depending upon the dietary intake. Other useful sources are whole grain cereals, bread, tea, and coffee.
Human milk contains a higher concentration of niacin than cow’s milk. In plants, especially in mature cereal grains like corn and wheat, niacin may be bound to sugar molecules in the form of glycosides, thus significantly reducing niacin bioavailability.
B3 (niacin) is important as it helps the body to
• convert food into glucose, used to produce energy
• produce macromolecules, including fatty acids and cholesterol
• DNA repair and stress responses.
Most people in the United States get enough niacin from the foods they eat. Niacin deficiency is very rare in the United States.
Food sources of vitamin B3