Niacin, also known as vitamin B3, is a water-soluble vitamin involved in numerous aspects of metabolism. It aids in the conversion of food into usable energy, and helps keep the skin, hair, eyes, and liver healthy.
Sources of niacin include meat, poultry, fish, fortified cereals, and peanuts. Adults generally need about 14-16 milligrams of niacin per day. Severe deficiency in niacin can lead to pellagra, characterized by diarrhea, dermatitis, dementia, and even death if not treated.