Nicotinamide adenine dinucleotide (NAD⁺) is a coenzyme present in all living cells, derived from vitamin B3 (niacin) precursors. It functions as an electron carrier in redox reactions and as a substrate for NAD⁺-consuming enzymes including sirtuins, PARPs, and CD38.

NAD⁺ levels have been observed to decline with age in research models, which has motivated extensive study of NAD⁺ biology in the context of aging, mitochondrial function, DNA repair, and metabolic disease. Research has also examined NAD⁺ precursors such as NMN and NR.

It is used as a reference cofactor in studies of cellular metabolism and aging biology.

For research purposes only. Not for human consumption.