Nutrient glossary

What is vitamin B3 (Niacin)?

Niacin runs the redox reactions that release energy in every cell; meat, fish and peanuts are dense in it.

Reviewed 20 July 2026. General information, not medical advice.

The short version

Niacin forms NAD, the molecule at the centre of turning food into energy and repairing DNA. Meat, fish, peanuts and wholegrains carry it directly, and the body can also make some from the amino acid tryptophan.

True deficiency (pellagra) is rare where diets contain protein, so for most people niacin quietly takes care of itself.

Daily reference

16.5 mg a day

The reference is 16.5 mg a day for men and 13.2 mg for women. High-dose supplements cause flushing and belong under medical advice.

This is the fixed adult reference used across these pages. In the app, your amount adjusts to your body and way of eating.

Best food sources of vitamin B3 (Niacin)

Full ranking
FoodPer servingPer 100g
Tuna Steak28.7 mg22.1 mg
Chicken Breast23.3 mg13.7 mg
Beef Liver14.9 mg17.5 mg
Duck Breast14.6 mg10.4 mg
Turkey Breast14.2 mg11.8 mg
Tuna (canned)14 mg11.7 mg
Salmon Fillet12.9 mg8.6 mg
Roast Chicken12.8 mg9.2 mg

Common questions

What is a niacin flush?
Doses of nicotinic acid well above food levels dilate skin blood vessels, causing hot red tingling for an hour or so. Food never does this.
Which foods are highest in niacin?
Chicken breast, tuna, turkey, peanuts and fortified cereals top the everyday list.