Description
Niacin (nicotinic acid and nicotinamide) is used by the body to form coenzymes such as nicotinamide adenine dinucleotide (NAD+) and nicotinamide adenine dinucleotide phospate (NADP+). As many as 200 enzymes require the two coenzymes, NAD+and NADP+, mainly to accept or donate electrons for redox reactions. NAD+ functions most often in reactions involving the degradation (catabolism) of carbohydrates, fats, proteins, and alcohol to produce energy. NADP+ functions more often in biosynthetic (anabolic) reactions, such as in the synthesis of fatty acids and cholesterol. Since almost every metabolic pathway uses either NAD+ or NADP+, it is not surprising to find signs and symptoms of niacin deficiency in severe metabolic disorders. One of the most severe diseases is know as pellagra, which is characterized by the four Ds: dermatitis, diarrhea, dementia and death.
