Vitamin B3 (Niacin)

By Dietitian Juliette Kellow BSc RD

How much you need each day:

  • 13mg for adult women up to 50 years; 12mg for adult women over 50 years
  • 17mg for adult men up to 50 years; 16mg for adult men over 50 years

Why you need it:

Like B1 and B2, vitamin B3 releases the energy from carbohydrates, fats and proteins so they can be used by the body.

This vitamin is also involved in controlling blood sugar levels, keeping skin healthy and maintaining the proper functioning of the nervous and digestive systems.

Good food sources:

Vitamin B3 tends to be found in foods that are good sources of protein such as red meat, poultry, fish and nuts, although potatoes, pasta and yeast extract also contain this vitamin.

Some foods such as bread and breakfast cereals are also fortified with niacin.

The body is also able to make niacin from an amino acid (protein building block) called tryptophan. This means foods that are a good source of tryptophan such as eggs, milk, cheese and yoghurt, can contribute to recommended intakes for niacin.

Too little:

A deficiency of this vitamin is rare but causes skin problems, weakness, fatigue and a loss of appetite.

In extreme cases, a condition called pellagra develops, which is mainly seen in third world countries. This is characterised by weight loss, skin problems, diarrhoea, depression and in severe cases, dementia.

Top tip:

If you eat a balanced, varied diet containing foods from the four main food groups, it’s unlikely you’ll be short on vitamin B3 as it’s found in lots of different foods.

How to get enough:

Food Vitamin B3 Content (mg)*
150g grilled skinless chicken breast 33
100g steamed salmon steak 10.8
220g jacket potato 4.4
150g cooked wholewheat pasta 3.5
100g cottage cheese 3.3
1 Weetabix 2.7

* This includes the niacin that’s made from the amino acid tryptophan.

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