Vitamin
Vitamin B3
Vitamin B3 (niacin) helps release energy from food and keeps the nervous system and skin healthy. It is found in meat, fish, and fortified foods.
What it is
Niacin is a water-soluble B vitamin. The body can also make some niacin from the amino acid tryptophan found in protein foods.
What it does
It helps the body release energy from food and keeps the nervous system and skin healthy.
Good sources
Meat, fish, wheat flour, eggs and milk, and fortified breakfast cereals.
Deficiency and who is at risk
Deficiency is rare in the UK. Severe lack causes a condition called pellagra, with skin, digestive and mental changes. People with very poor diets or certain conditions are more at risk.
Balance
Can you have too much?
High doses of niacin from supplements can cause skin flushing and, in large amounts over time, liver problems, so it should not be taken in high doses without medical advice.
Education and reference only. This is general nutrition information, not personal advice, and does not give doses. Ask a pharmacist, GP or registered dietitian before starting supplements, especially with a health condition or in pregnancy.
Answers
Vitamin B3: frequently asked questions
Can niacin cause flushing?
Yes. High doses, particularly of one form of niacin used in supplements, can cause temporary skin flushing, warmth and tingling. This is one reason high-dose niacin should only be taken on medical advice.
Do I need a niacin supplement?
Most people get enough niacin from a normal diet containing meat, fish, eggs, dairy or fortified cereals, and do not need a supplement.
Related
More on vitamins and nutrition
Sources
Where this is drawn from
- NHS — Vitamins and minerals
- British Dietetic Association (BDA)
- UK Scientific Advisory Committee on Nutrition (SACN)
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