NAD is the abbreviation of Nicotinamide Adenine Dinucleotide. NAD is white powder, easily soluble in water, in soluble in organic solvents. NAD exists in two forms: oxidized form NAD+ and reduced form NADH. In metabolism, NAD is a cofactor, involved in redox reactions, by carrying electrons from one reaction to another. NAD powder is extracted from yeast. NAD powder is helpful for improving metabolism. It can potentially prolong the lifespan of cells, thus it may have anti-aging effect. NAD powder can be used in supplements, and it is also be added to pharmaceuticals for treatment of various diseases.