NAD+

NAD+, or nicotinamide adenine dinucleotide, is not a peptide but a central coenzyme involved in cellular energy metabolism, redox balance, mitochondrial function, DNA repair, and sirtuin signaling. Researchers study NAD+ because its levels and related pathways are connected with aging, metabolic stress, inflammation, and cellular resilience. It plays a key role in converting nutrients into usable cellular energy and supporting enzymatic processes that regulate repair and stress response. NAD+ research spans mitochondrial biology, longevity science, neurobiology, metabolic function, and cellular recovery. It is best categorized as a foundational cellular-energy compound.