Another name for vitamin B3 is niacin or nicotinic acid. It is one of the eight vitamins that make up the vitamin B complex group. Like the other vitamins in this group, it is water soluble and hence the likelihood of toxicity due to over-consumption of the vitamin is unlikely. This is because instead of an accumulation of the excess niacin in the body, it is excreted in urine. For the same reason, a steady supply of the vitamin is needed for optimal health.

It is important to note that the term nicotinic acid has nothing to do with the nicotine found in tobacco.

Functions of niacin in the body

The main function is in the production of energy, the fuel the body needs to run all other functions. The vitamin is needed as a co-enzyme by more than 200 enzymes for their chemical reactions in the body. Under certain circumstances, the body can synthesize its own niacin from the amino acid called tryptophan.

It plays a role in signaling mechanisms that regulates the activities of body cells. Research indicates that the vitamin also protects the DNA against damage and also plays a role in its repair.

Signs and symptoms of vitamin B3 deficiency

In the U.S and other developed world countries, niacin deficiency is very rare. However, low grade or even obvious deficiency can be observed in some groups of people. According to CDC’s Second Nutrition Report, this can happen to different people as determined by:

  • Age
  • Gender
  • Race
  • Economic status can also determine the state of niacin in a person.

Common signs and symptoms of mild vitamin B3 deficiency include:

  • Digestion problems
  • Generalized tiredness
  • Nausea with or without vomiting
  • Depression
  • Mouth sores (canker sores)
  • Poor circulation

Severe niacin deficiency leads to a serious health condition called pellagra.

Signs and symptoms of pellagra

This is a disease associated with severe poverty and hence has been called a disease of poverty. In addition to the mild niacin deficiency symptoms listed above, the others include:

  • The classic 3 Ds. These are dementia, diarrhea and dermatitis (skin problems). Without treatment, a fourth D (Death) is inevitable.
  • Hair-loss
  • Tongue inflammation
  • Vaginal inflammation
  • Esophagus inflammation
  • Neurological symptoms that include irritability, aggression, depression and seizures. Impaired sensations are also likely to occur.
  • The skin problems include pigmentation of areas exposed to the sun and a characteristic ring-like skin changes on the neck (referred to as Casal’s necklace)

Although severe pellagra can easily cause death, giving vitamin B3 supplements orally leads to noticeable improvement of skin lesions in as short as 24 to 48 hours.

Who is at risk of vitamin B3 deficiency?

  1. Extremely poor people
  2. Mainly corn-based diet
  3. Low tryptophan diet
  4. Alcoholics
  5. Anorexics
  6. Disease conditions such as the genetically determined poor nutrient absorption disease, Hartnup’s disease and the Carcinoid syndrome.
  7. Fad diets. The desire to lose weight fast without much physical activity (using diet alone) is making pellagra gradually creep back into the U.S as discussed in a study published in the American Journal of Therapeutics of March-April 2008
  8. Prolonged use of the drug Isoniazid
  9. Dialysis patients
  10. Immune-suppressed people such as those suffering from HIV/AIDS

Sources of vitamin B3

There are animal and plant-based sources of vitamin B3. Here we list plant sources of the vitamin. They include:

  • Peanuts peanut butter
  • Mushrooms
  • Avocado
  • Sunflower seeds
  • Green peas
  • Yeast extract
  • Rice bran
  • Grounded pepper
  • Tomatoes (sun-dried)
  • Paprika

Vitamin B3 is also available in form of nutritional supplements and as a pharmacological product.

How vitamin B3 keeps you healthy

  1. Glucose metabolism
    It has been found that vitamin B3 (as nicotinamide) helps to protect the beta cells in the pancreas against free radicals damage. The damage to these cells is what leads to insulin-dependent diabetes mellitus (IDDM). Identifying high risk groups for IDDM and putting them on niacin supplements may help to prevent the development of diabetes.
  2. Has antioxidant properties
    Supports the control of free radicals in the body and therefore reduces the risk of many degenerative health conditions such as osteoarthritis, rheumatoid arthritis and cancer.
  3. Reduces the risk of cancer
    The vitamin has protective properties against DNA and chromosomes damage.
  4. Supports healthy bone marrow proliferation
    This has been observed in patients on chemotherapy where the anti-cancer drugs used usually suppress the bone marrow. This means it can be an adjunct part of cancer treatment. One study concludes that niacin may hold the ability to prevent secondary cancers associated with certain chemotherapy medications.
  5. May be useful in the management of psychiatric disorders such as schizophrenia.
    Pellagra can manifest with psychiatry signs and symptoms. Researchers theorize that since pellagra mental symptoms do improve with niacin administration; then it may be possible to use it in schizophrenia. Research along this line is however, in its early stages.
  6. Helps in HIV/AIDS management
    Early studies indicate that vitamin B3 slows the progression of HIV to full-blown AIDS. It has also been observed that the plasma tryptophan increases with the vitamins supplementation. HIV usually leads to low tryptophan level. It has also been shown to improve heart health in the same group of patients. According to the Oregon State University’s Linus Pauling Institute, heart disease is the second commonest cause of death in HIV?AIDS patients. This is partly due to the effects of medications used in the treatment.
  7. Supports cardiovascular health
    Vitamin B3 has cholesterol regulation properties. It lowers the bad type and increases the good type. It also lowers triglycerides (a type of fat). All these work together to reduce the risk of cardiovascular disease (CVD)

Other benefits of vitamin B3

  • Supports skin health
  • Reduces arthritis pain
  • Supports brain functions
  • Lowers risk of cataract development

Safety and precautions:

Vitamin B3 when used as recommended is safe. Taking high doses may cause ‘niacin flush’. This is a condition that presents with transient dose-related skin symptoms. People with impaired liver functions are advised to consult their doctor before using niacin. This vitamin may interact with certain medications and so it is advisable to consult your doctor if you are on medication for any health condition.


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