These compounds are precursors of the co-enzymes nicotinamide adenine dinucleotide and nicotinamide adenine dinucleotide phosphate, which is directly or indirectly involved in many metabolic functions including the digestive system, skin, and nerves.
Human bodies also use niacin to convert nutrients into energy, to make fats and cholesterol and to form and repair our genetic material (DNA).
Niacin vitamers are found in both plant and animal foods, and due to the contribution of tryptophan, foods containing balanced protein may also contribute to high niacin equivalent. Niacin can be sourced from a variety of foods but some of the richest sources include: liver, meat and meat products, fish, peanuts, whole grains, fortified foods.
Niacin is present in a wide variety of foods. Many animal-based foods—including poultry, beef, and fish—provide about 5-10 mg niacin per serving, primarily in the highly bioavailable forms of NAD and NADP. Plant-based foods, such as nuts, legumes, and grains, provide about 2-5 mg niacin per serving, mainly as nicotinic acid.
Its deficiency is apparent in conditions of poverty, malnutrition, chronic alcoholism psychosis, and some types of tumor. Mild niacin deficiency can slow metabolism, and cause headaches and other minor symptoms, but severe deficiency causes the disease pellagra, characterized by diarrhea, dermatitis and other skin disorders, dementia, inflammation of the mouth and tongue, and other symptoms which can be fatal if left untreated.
If supplemented at pharmacological level, niacin compounds provide potential health benefits like combating cardiovascular disease, diabetes, osteoarthritis, neurological problems, and skin diseases. Apart from having such benefits, excess doses of niacin could lead to side effects.
Niacin (Vitamin B3)
