Functions of Vitamin B3
Niacin is a coenzyme involved in the metabolism of proteins, fats, and carbohydrates. Besides its presence in food, the vitamin is manufactured in the body from the essential amino acid tryptophan. It is important for blood circulation and reducing cholesterol levels in the blood. It is essential for growth and hormone synthesis
Deficiency of Vitamin B3 or Niacin
At the present time, niacin deficiency is rarely seen in developed countries, but it is usually apparent in conditions of poverty, malnutrition, and chronic alcoholism.
Symptoms of mild deficiency include indigestion, fatigue, canker sores, vomiting, and depression. Severe deficiency can cause a condition known as pellagra. Pellagra results from combined deficiency of niacin and tryptophan. Long term deficiency leads to central nervous system dysfunction manifested by confusion, apathy, disorientation. Pellagra is characterized by cracked, scaly skin, dementia, and diarrhea. It is generally treated with a nutritionally balanced diet and niacin supplements. Niacin deficiency also results in burning in the mouth and a swollen, bright red tongue. Hartnup’s disease is a hereditary nutritional disorder resulting in niacin deficiency.
Large doses cause a flushing of the skin as a result of the dilation of blood vessels but the effect is not harmful. Large doses can damage the liver and cause depression in some people. High doses of niacin should not be taken during pregnancy, or in cases of ulcers, gout, diabetes, gallbladder or liver diseases, or recent heart attack.