Vitamin B3 is also known as niacin, nicotinic acid and vitamin PP.
It is one of the group of B vitamins.
See also an overview of the main vitamins.
Active Forms of Vitamin B3:
There are two active forms of vitamin B3:
- Nicotinamide adenine dinucleotide (NAD), and
- Nicotinamide adenine dinucleotide phosphate (NADP)
Functions of Vitamin B3:
The main functions of vitamin B3 include:
- In common with vitamin B1 (thiamin) and vitamin B2 (riboflavin), vitamin B3 helps with the release of energy from foods and the use of oxygen in the cells of the body. - NAD+ and NADP+ are coenzymes for several dehydrogenases in redox reactions (this information is useful to people who also need to understand the chemical reactions within the body, i.e. details about metabolism)
- Promotion of healthy growth and development (in children) and to maintain healthy skin, digestive function and nervous system.
- Supports heart health and circulation.
- Production of steroid hormones in the adrenal glands.
- Supports balanced mental and emotional outlook.
- DNA repair. Specifically, NAD is needed to repair DNA in exposes areas of skin that have been damaged by UV light e.g. due to sunburn.
Sources of Vitamin B3:
There are many different types of foods that include some vitamin B3.
Examples of sources of vitamin B3 include:
Fruits, nuts/seeds and vegetables:
- Brewer's yeast
- Wholegrain cereals
- Breakfast cereals fortified with vitamin B3
- Wholemeal bread
- Fish e.g. tuna, salmon
- Lean meat e.g. beef
- the amino acid tryptophan (but synthesis of vitamin B3 from tryptophan is inefficient, requires vitamins B1, B2 and B6 as cofactors and only after protein synthesis requirements have been met)
- some nuts e.g. peanuts
- some seeds e.g. sunflower seeds
- green leafy vegetables e.g. cabbage
Vitamin B3 is also included in some dietary supplements e.g. multi-vitamin tablets or capsules.
The vitamin B3 content of foods is depleted by food processing, incl. preserving and cooking.
Problems due to insufficient or too much Vitamin B3:
Possible consequences of deficiency of Vitamin B3 include:
Possible consequences of excessive intake of Vitamin B3 include:
See also what is a balanced diet? .