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Vitamin B3

Niacin (Nicotinic acid or Nicotinamide) is an essential dietary vitamin that belongs to the B group vitamins.

Vitamin B3 is essential for the activity of many enzymes in the body. Enzymes are special substances that speed up chemical reactions in the body. These enzymes are responsible for the production of energy in the body, the breakdown of dietary fats, the production of certain hormones and cholesterol, the processing of genetic material (DNA) and the growth and maturation of the cells in the body. Vitamin B3 is absorbed rapidly from the gut, transported to all the body tissues and any excess is excreted in the urine. Large doses of Vitamin B3 can cause flushing of the skin and liver abnormalities, although both of these problems disappear when the vitamin is broken down and excreted by the body.


Always consult your Doctor for advice on dosages and drug interactions before taking any dietary supplements.

· The Nicotinic Acid form of Vitamin B3 is used medically to treat and prevent Vitamin B3 deficiency (pellagra) and to lower the blood cholesterol levels of patients with high cholesterol levels.

· Nicotinamide may also be given to people with certain types of cancer, such as bladder cancer, prior to radiotherapy, as it can make cancer cells more sensitive to this treatment.

· There is some evidence to suggest that a high intake of Niacin, particularly from food sources, may help to reduce the risk of Alzheimer's disease.


A deficiency of Vitamin B3 causes a condition called pellagra. Pellagra is most often seen in chronic alcoholism, malnutrition and people with multiple vitamin deficiencies. Pellagra causes dermatitis, diarrhoea and dementia. There is also a bright red rash resembling sunburn, irritation of the mouth, inflammation and ulceration of the tongue, nausea and vomiting, insomnia, depression, headache dizziness, delusions, hallucinations and anaemia.


Good food sources of Vitamin B3 include yeast (e.g. Brewer's yeast), meat (particularly liver), fish, poultry, dairy products, eggs, cereals such as rolled oats porridge, rice or wheat with lesser amounts in corn, legumes (beans and peas), seeds and leafy green vegetables.


The recommended dietary intake (RDI) of Vitamin B3 is 19 mg per day for adult males and 13 mg per day for adult females, although females who are pregnant require 15 mg per day and those that are lactating require 18mg per day. Much larger doses of Vitamin B3 may be given for specific medical conditions under the supervision of a qualified health care professional.

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