NMN is a direct precursor to NAD+ — the coenzyme required by ALL living cells for energy metabolism, DNA repair, and sirtuin activation. NAD+ levels decline ~50% by age 60, and this decline is increasingly recognized as a driver of aging. David Sinclair's lab showed NMN reversed age-related muscle decline, improved insulin sensitivity, and extended healthspan in mice. The first human RCTs are now confirming NAD+ elevation: a 2022 study found 250mg/day increased blood NAD+ by 38% in 12 weeks. NMN competes with NR (nicotinamide riboside) as the preferred NAD+ precursor — the debate is ongoing, but NMN was FDA-cleared for GRAS status in 2023 and has more recent clinical trials.
NMN → NAD+ via the enzyme NMNAT (nicotinamide mononucleotide adenylyltransferase) in a single enzymatic step. This is the most direct precursor pathway to NAD+. Once NAD+ is restored: (1) sirtuins (SIRT1-7) are activated — deacetylases that regulate gene expression, mitochondrial function, and DNA repair; (2) PARPs (DNA repair enzymes) function more efficiently; (3) CD38 (NAD+ consumer that increases with age and inflammation) is counteracted; (4) mitochondrial electron transport chain efficiency improves (NAD+/NADH ratio). The age-related NAD+ decline is driven by: increasing CD38 expression (inflammatory NAD+ consumption), decreasing NAMPT expression (NAD+ synthesis enzyme), and accumulating DNA damage (PARP consumption).
No critical interactions identified.
Reviewed by the Scan Dose Research Team and Clinical Advisory Board | Last updated:
Not medical advice. Based on published clinical research and systematic reviews.