NMN
Raises NAD+ levels to support cellular energy, DNA repair, and longevity pathways.
What is NMN?
NMN (nicotinamide mononucleotide) is a precursor to NAD+ (nicotinamide adenine dinucleotide), a coenzyme involved in energy metabolism and DNA repair. NAD+ levels decline significantly with age: by age 50, most people have roughly half the NAD+ levels of a 20-year-old. Sirtuins, the longevity proteins studied extensively by David Sinclair at Harvard, depend on NAD+ to function.
What does the evidence say?
Animal research has been compelling: studies in mice show NMN supplementation improves insulin sensitivity, energy metabolism, and lifespan markers. Human data is now emerging. A 2021 randomised controlled trial by Yoshino et al. in Science found NMN at 250mg/day for 10 weeks improved muscle insulin sensitivity and NAD+ levels in postmenopausal women. A 2022 study by Yi et al. found improvements in physical performance in older adults. Human trials are still early-stage.
Promising early research, but larger independent trials are needed before drawing firm conclusions.
Dosage guide
| Effective dose | 250–500mg per day |
| Maximum dose | 1,000mg/day (used in human studies without significant adverse effects) |
| Timing | Morning. NAD+ supports circadian rhythm function. |
Best form to buy
Stabilised NMN powder or sublingual NMN for faster absorption. NMN degrades in heat and light: buy from reputable suppliers who test purity and maintain cold storage.
Who benefits most
Men over 40 interested in longevity optimisation, those with notable fatigue or metabolic concerns, and anyone following Sinclair's longevity protocol.
Side effects and safety
Generally well tolerated in human trials to date. Some users report mild nausea at high doses. Long-term safety data in humans is still accumulating.
“This is the most genuinely exciting emerging longevity supplement. The mouse data is extraordinary, the human data is early but promising, and the mechanism is well understood. Expensive and not yet proven in long-term human trials, but the risk-benefit makes it worth considering for serious longevity-focused men over 45.”