NAD+ (Nicotinamide Adenine Dinucleotide) is a coenzyme found in every living cell, central to redox reactions, mitochondrial energy production, and DNA repair pathways. It cycles between oxidized (NAD+) and reduced (NADH) states as part of core metabolic processes, making it essential to how cells generate usable energy from nutrients. Beyond energy metabolism, NAD+ also acts as a substrate for sirtuins and PARP enzymes, two enzyme families closely tied to cellular ageing, DNA damage response, and gene expression regulation. NAD+ levels are known to decline steadily with age across multiple tissue types, a pattern that has made it one of the most widely studied compounds in longevity and mitochondrial function research. Current research interest spans cellular energy production, oxidative stress response, and the broader biology of age-related metabolic decline.

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