Vitamin B3 – niacin

Why do you need it?

Vitamin B3 (niacin) helps to release energy from your food and is essential for many basic reactions in the body. It also helps to maintain your nervous system and keep your skin healthy. There are two forms of niacin: nicotinic acid and nicotinamide, both of which are found in food. The amino acid tryptophan (a component of some proteins) is also converted by our bodies to nicotinamide.


Deficiency can lead to lesions on skin exposed to sunlight and/or pressure, diarrhoea and in extreme cases, loss of mental capacity. The disease caused by severe niacin deficiency and characterised by these symptoms is called pellagra – a chronic wasting disease.

How much do you need?

The World Health Organisation recommends 14 milligrams of niacin (vitamin B3) a day for women and 16 milligrams a day for men. The recommended intakes for infants, children and adolescents, as well as pregnant and lactating women are given below.

Recommended nutrient intakes for niacin. Click to read more…
Age groupRecommended nutrient intake mg/day
Infants and children
0-6 months2
7-12 months4
1-3 years6
4-6 years8
7-9 years12
Females 10-18 years16
Males 10-18 years16
Females, 19+ years14
Males, 19+ years16
Pregnant women18
Lactating women17
Source: WHO, FAO. 2004. Vitamin and mineral requirements in human nutrition. 2nd ed. Geneva: WHO.

NB The numbers given are for NE = niacin equivalents (niacin or niacinamide), a 60-to-1 conversion factor is required for tryptophan to niacin.

Where to find vitamin B3 (niacin)

The best plant sources of niacin include peanuts, avocados, wholegrain foods, mushrooms, green leafy vegetables, sweet potatoes, bananas and seeds. 

  • Peanuts (groundnuts): Widely grown in Uganda, peanuts can be roasted and eaten as a snack or used in sauces and spreads. They are a great source of niacin with one small handful (28 grams) of peanuts providing 4.2 milligrams of niacin.
  • Avocados: Another great source of niacin, one medium avocado (201 grams) can provide 3.5 milligrams of niacin.  Use in salads, sandwiches or chop and serve as a side dish with beans. 
  • Wholegrains: Brown rice, quinoa and barley contain niacin. One cup (195 grams) of cooked brown rice contains five milligrams – around one-third of your daily needs.  
  • Mushrooms: Although not widely available in Uganda, mushrooms are a good source of niacin. They can be added to soups, stews or stir-fries.
  • Green leafy vegetables: Vegetables like spinach, kale, and collard greens are good sources of niacin. They can be eaten raw in salads or cooked in various dishes.
  • Pulses: Popular varieties include yellow, green and split peas, red kidney beans, black beans, mung beans, cowpeas (black-eyed peas) and red ‘masoor’ lentils. They are a versatile staple in Uganda and are used in curries, soups, stews, salads or simply boiled and served as a side dish. They are good sources of niacin and one cup (198 grams) of cooked lentil contains 2.1 milligrams of niacin.
  • Seeds: Sunflower and pumpkin seeds are a great source of niacin and can be eaten as a snack or sprinkled on dishes such as soup or salad. A small handful (28 grams) of sunflower or pumpkin seeds contains 2.0 and 1.3 milligrams of niacin respectively. 
  • Sweet potatoes: Sweet potatoes are a moderate source of niacin and can be baked or used in soups, stews or roasted as a side dish. A medium sweet potato (130 grams) contains 0.7 milligrams of niacin. 
  • Bananas: Bananas are a good source of niacin and can be eaten on their own or added to smoothies or porridge. One medium banana (126 grams) contains 0.8 milligrams of niacin.

Corn (maize) contains good levels of niacin but can’t be relied on because it is tightly bound to starches in the grain – making it hard to absorb in the body. In some countries, corn is soaked in limewater overnight (alkaline treatment) before milling. This process, called nixtamalization, softens the corn and releases its niacin. This method is used to cook tortillas in Central America where pellagra is rare. Unless the maize flour is fortified or the corn has been nixtamalized, maize cannot be relied on as a source of niacin, a varied diet is best.