Niacin, also known as vitamin B3 or nicotinic acid, is a water-soluble B vitamin that plays a crucial role in various bodily processes, including energy metabolism and DNA repair. As a food additive, niacin is often used to enrich and fortify foods with essential nutrients that may be lost during processing. It’s commonly added to foods like breakfast cereals, bread, and other processed foods to ensure that consumers receive adequate amounts of it from their diet. Niacin can be produced through chemical synthesis or extracted from natural sources, such as yeast, and then purified for use in food products.