What you've heard
NAD+ boosters and other longevity supplements slow aging
Verdict
Unsupported so far
Do NAD+ boosters and longevity supplements slow aging?
Unsupported so far.
Supplements called NR and NMN reliably raise blood levels of NAD+, a molecule cells use to handle energy. The trouble is what happens next. One pooled analysis of the small NMN trials found blood levels rising but "most of the clinically relevant outcomes were not significantly different," and others found no clear gain in blood sugar, cholesterol, muscle or walking speed, and perhaps a small drop in the lower blood pressure number. No human trial has measured lifespan or age-related disease. Senolytics, drugs meant to clear worn-out cells, are further from the shelf than their marketing suggests: the first human test gave dasatinib, a leukemia drug, with quercetin, a supplement-aisle compound, to a handful of people for three days, with no comparison group, and counted cells rather than health.38 Dasatinib has real toxicity. That is not a supplement decision.
Where the book tests it
Sources
- 38.Martens, C.R., Denman, B.A., Mazzo, M.R., Armstrong, M.L., et al. (2018). "Chronic nicotinamide riboside supplementation is well-tolerated and elevates NAD+ in healthy middle-aged and older adults." Nature Communications, 9(1), 1286. https://doi.org/10.1038/s41467-018-03421-7; Zhang, J., Poon, E.T., and Wong, S.H. (2025). "Efficacy of oral nicotinamide mononucleotide supplementation on glucose and lipid metabolism for adults: a systematic review with meta-analysis on randomized controlled trials." Critical Reviews in Food Science and Nutrition, 65(22), 4382-4400. https://doi.org/10.1080/10408398.2024.2387324; Prokopidis, K., Moriarty, F., Bahat, G., McLean, J., et al. (2025). "The effect of nicotinamide mononucleotide and riboside on skeletal muscle mass and function: a systematic review and meta-analysis." Journal of Cachexia, Sarcopenia and Muscle, 16(3), e13799. https://doi.org/10.1002/jcsm.13799; Chen, F., Zhou, D., Kong, A.P., Yim, N.T., et al. (2024). "Effects of nicotinamide mononucleotide on glucose and lipid metabolism in adults: a systematic review and meta-analysis of randomised controlled trials." Current Diabetes Reports, 25(1), 4. https://doi.org/10.1007/s11892-024-01557-z; Zhang, M., Chen, Y., Jiang, N., Zeng, J., et al. (2026). "Effects of nicotinamide mononucleotide supplementation on blood pressure: a systematic review and meta-analysis of randomized controlled trials." Nutrients, 18(6), 890. https://doi.org/10.3390/nu18060890; Hickson, L.J., Langhi Prata, L.G.P., Bobart, S.A., Evans, T.K., et al. (2019). "Senolytics decrease senescent cells in humans: preliminary report from a clinical trial of Dasatinib plus Quercetin in individuals with diabetic kidney disease." EBioMedicine, 47, 446-456. https://doi.org/10.1016/j.ebiom.2019.08.069 (Zhang 2025 pooled 12 studies and 513 people; the senolytic study treated nine people.)
Note numbers are those of Chapter 16, Aging Well.
This verdict is one of the "What you've heard" boxes in Chapter 16, Aging Well, where the book tests the claims people repeat against the studies behind them.
Educational content, not medical advice. Disclaimer.