Niacinamide (nicotinamide) is a form of vitamin B3. Niacinamide is a water-soluble vitamin. Your body needs it to create energy, and your cells need it to function correctly. Water-soluble vitamins are not stored in the body and must be regularly consumed through food or supplements. To make things even more interesting, the umbrella “vitamin B3” includes nicotinic acid and nicotinamide. Niacinamide and nicotinic acid (aka “niacin”) are common forms of vitamin B3 found in supplements. Your body can convert tryptophan from food into niacinamide as needed, and it may be able to make niacinamide from niacin to an extent when there's enough of it.