Vitamin B3, colloquially referred to as niacin , is a vitamin family that includes three forms, or vitamers: nicotinic acid ( niacin ), nicotinamide (niacinamide), and nicotinamide riboside. [1][2] All three forms of vitamin B 3 are converted within the body to nicotinamide adenine dinucleotide (NAD). [1][3] NAD is required for human life and people are unable to make it within their bodies without either vitamin B 3 or tryptophan. [1] Nicotinamide riboside was identified as a form of vitamin B ... Vitamin B3 is also known as niacin . Having enough niacin in the body is important for general good health because your body uses it to turn food into energy. B3 is also essential for the health... Niacin is a drug used to treat high cholesterol and high triglycerides. Learn about side effects, drug interactions, dosages, warnings, and more.