Niacin

Niacin, also known as vitamin B3 or nicotinic acid, is a water-soluble vitamin that is used by the body to convert carbohydrates into sugar (glucose), which the body then uses for energy. Niacin also helps keep the nervous system, digestive system, skin, hair and eyes healthy. That's why niacin is often a part of a daily multivitamin, though most people get enough niacin from the food they eat.

Niacin is found in many foods, including dairy products, lean meats, poultry, fish, nuts and eggs. In addition, many breads and cereals have niacin added to them. Niacin is used to treat and prevent a lack of natural niacin in the body, and to lower cholesterol and triglycerides in the blood. It is also used to lower the risk of heart attack in people with high cholesterol who have already had a heart attack.

Severe deficiency of niacin in the diet causes the disease pellagra, whereas mild deficiency slows the metabolism, causing decreased tolerance to cold. Dietary niacin deficiency tends to occur only in areas where people eat corn (maize, the only grain low in niacin) as a staple food without lime added during meal/flour production.