Vitamin B3 (niacin)

Vitamin B3 (niacin)Vitamin B3 is water-soluble and because it does not get stored in the body we depend on regular intake of the nutrient. Niacin is a common term for nicotinic acid and nicotinamide. The body's metabolism is able to synthesise part of its required niacin from vitamin B6 and tryptophan, an amino acid which is primarily found in meat. Vitamin B3 is destroyed by heating.

Functions and importance for

Deficiencies and poor utilisation may be caused by

Levodopa against Parkinson's disease

Busulfan and mercaptopurine against cancer

Isoniazid against tuberculosis

Deficiency symptoms

Minor deficiency

Major deficiency

Left untreated, pellagra may lead to extreme weight loss, heart failure, and eventually death.

Pellagra is particularly common in countries where the population consumes unbalanced diets (mainly corn) and the body has difficulty with absorbing the vitamin. Lack of the amino acid tryptophan (mainly from animal protein) and poisoning caused by mycotoxins that grow on corn that has not dried properly increase the risk of pellagra.

Sources

Mainly foods that are rich in protein, for instance meat, fish, poultry, nuts, kernels, and sprouts. Other sources are eggs, whole-grain products, and fruit.

Content of vitamin B3 (niacin) in mg per 100 grams

Calf liver 20
Chicken 12
Salmon 10
Pumpkin seeds 9
Oats 3


Recommended daily allowance (RDA)

Adults: 11 years of age and older: 16 mg
Pregnancy and lactation: 17 and 19 mg
Children: 1-10 years of age: 9 mg

Important information

The declaration often lists NE or niacin equivalents instead of mg (milligram). This is because the amino acid tryptophan can also get turned into niacin in the body. The tryptophan content in a product is therefore converted in such a way that 60 mg of tryptophan equals 1 mg of niacin. NE represents the combined amount of niacin and converted tryptophan.

Increased need

Important

Supplements of vitamin B3 should normally be taken together with other B vitamins and not together with antacids.

Precautions

Pregnant women should not ingest large doses of niacin, as it may harm the fetus.

Overdosing - side effect (very large doses)