Nicotinamide riboside (NR) is a NAD+ precursor that increases intracellular NAD+ availability through the salvage pathway, primarily via NRK1-mediated phosphorylation, serving as a substrate for NAD+-dependent enzymes including sirtuins and PARPs. By restoring NAD+ levels—which decline with age—NR modulates multiple aging-related pathways including mitochondrial function, DNA repair, metabolic homeostasis, and cellular stress responses. In preclinical models, NR supplementation has demonstrated improvements in mitochondrial biogenesis, exercise capacity, metabolic flexibility, and lifespan extension in C. elegans and some mammalian models. Human clinical evidence remains limited but phase 2 trials show improvements in muscle insulin sensitivity, arterial stiffness, and cardiometabolic parameters; definitive healthspan or lifespan data in humans is absent, and long-term safety and efficacy require further investigation.
No. NR and NMN are both NAD+ precursors but are chemically distinct compounds, metabolized through different pathways. Both are sold as dietary supplements, not FDA-approved drugs.
Available data (e.g., Martens 2020) has examined surrogate cardiovascular markers such as aortic stiffness rather than hard clinical outcomes. See the full profile for indexed papers and trial status.
Both are currently graded Emerging on Geroevidence, reflecting a similarly early-stage human evidence base built primarily on surrogate endpoints.
Available human trials have not identified major safety signals at studied doses; long-term and high-dose safety data remain limited.
Both target NAD+ repletion through different metabolic pathways and currently hold similar Emerging evidence tiers. See the NMN profile for direct comparison.