Some links on this site are affiliate links. If you purchase through them, we may earn a small commission at no extra cost to you. We only recommend products we believe in.
90 days of 500mg NMN gave me a moderate HRV bump and a measurable but small HbA1c drop. Not the lifespan-changing experience the Sinclair marketing implies, but enough mechanism for me to keep running it as a stack with resveratrol and TMG. Manage expectations.
NMN - nicotinamide mononucleotide - has been the most discussed longevity molecule in research circles for the past five years. It's the precursor to NAD+ (nicotinamide adenine dinucleotide), a coenzyme involved in essentially every energy-producing reaction in the body.
David Sinclair at Harvard has been publicly taking NMN for years. The mouse studies are extraordinary. The human trials are catching up. But does any of this translate to meaningful, noticeable results for a 40-year-old man who trains, sleeps adequately, and eats reasonably well?
I spent 90 days taking Charava NMN to find out.
Why NAD+ Declines With Age
NAD+ is required for the function of sirtuins - proteins that regulate cellular stress responses, DNA repair, mitochondrial function, and metabolic efficiency. Sirtuins are essentially cellular maintenance workers, and they need NAD+ as their fuel.
The problem: NAD+ levels decline substantially with age. Research suggests NAD+ concentrations in human tissue fall by roughly 50% between young adulthood and middle age. This decline is accelerated by chronic inflammation, alcohol, poor sleep, UV exposure, and obesity.
With less NAD+, sirtuins slow down. DNA repair becomes less efficient. Mitochondria - the cellular energy factories - start to decline in function. Metabolic rate slows. The cascade of effects that we associate with "ageing" is partly a downstream consequence of this NAD+ depletion.
NMN is an immediate precursor to NAD+. It enters cells and is converted to NAD+ directly. The question is whether oral NMN supplementation actually raises NAD+ levels in human tissue - and whether that matters.
The Evidence Base
Does oral NMN raise NAD+?
Yes. A 2020 double-blind randomised controlled trial by Yoshino et al. at Washington University School of Medicine found that 250mg of NMN daily for 10 weeks significantly increased NAD+ levels in skeletal muscle in post-menopausal women with pre-diabetes. This was the first human trial to directly measure NMN's effects in tissue (rather than just blood).
A 2022 trial published in Frontiers in Aging found that 600mg of NMN daily for 60 days significantly increased whole-blood NAD+ levels in healthy adults and improved measures of fatigue.
Does higher NAD+ translate to longevity benefits in humans?
This is where the evidence is still emerging. Mouse data is extraordinary - NMN has reversed aspects of vascular ageing, improved muscle endurance in aged mice, and extended lifespan in some models. Human trials are shorter and smaller by necessity. Current evidence points toward improvements in energy, muscle function, sleep quality, and metabolic markers, but the long-term longevity effect in humans is not yet established.
Why Charava
I chose Charava for a few reasons.
Dosage. Charava's NMN comes in 500mg capsules. Most positive human trials have used 250โ1,000mg daily. Many cheaper NMN supplements on Amazon provide 150โ200mg - doses likely below the threshold for meaningful NAD+ elevation.
Third-party testing. Charava provides Certificates of Analysis from independent labs confirming NMN purity and concentration. The NMN market has a contamination and underdosing problem. A 2022 analysis of commercially available NMN supplements found that several contained significantly less NMN than labelled. Third-party testing is non-negotiable.
Formulation. Charava uses pure ฮฒ-NMN (the biologically active form). Some cheaper products use a mixture of NMN isomers with lower bioavailability.
UK brand. Charava is a British longevity supplement company, which matters for quality control and customer service.
The Protocol I Used
- Dose: 500mg NMN daily (one Charava capsule)
- Timing: First thing in the morning, on an empty stomach - based on research suggesting NMN absorption is better in a fasted state
- Combined with: Resveratrol 500mg (Charava also makes this - resveratrol activates SIRT1, a sirtuin that NAD+ supports), and TMG (trimethylglycine) 500mg to support methylation
- Duration: 90 days
I did blood work at baseline and at 90 days. I was primarily looking for changes in metabolic markers, inflammatory markers, and energy.
What Changed
Energy and recovery: This was the most noticeable change, and it showed up within the first 3โ4 weeks. My usual mid-afternoon energy dip - consistent for years - significantly reduced. Not eliminated, but noticeably better. I was also recovering faster from training sessions.
Sleep quality: My HRV (tracked via Oura ring) improved moderately over the 90-day period. Average resting HRV went from 44ms to 51ms. Sleep stages data showed slightly more deep sleep in weeks 8โ12 compared to baseline. This is consistent with research showing NMN's effects on circadian rhythm regulation.
Metabolic markers: My HbA1c dropped from 37 mmol/mol to 34 mmol/mol (both within normal range but moving in the right direction). Fasting insulin also improved slightly. These are modest changes but directionally consistent with the NAD+/sirtuin pathway's role in insulin sensitivity.
Mental clarity: Harder to quantify, but subjectively I noticed improved focus during sustained work periods. This aligns with what I'd expected from the literature on NAD+ and neurological function.
What didn't change: Total testosterone didn't move significantly. Inflammatory markers (hsCRP) were unchanged. Lipids were unchanged. NMN isn't a testosterone booster - don't expect it to function like one.
What to Realistically Expect
NMN is not a drug with an acute, obvious effect. It doesn't give you a jolt of energy like caffeine. The mechanism is cellular - you're slowly restoring a coenzyme that supports hundreds of enzymatic processes. The effects accrue gradually over weeks and months.
Men who typically report the most noticeable effects from NMN are over 40 (where baseline NAD+ decline is most relevant), already optimising sleep and training (so the marginal gains from NMN are clearer against a clean background), and consistent in their supplementation.
If you're 35, sleeping 6 hours, eating poorly, and not exercising - NMN is not where to start. Address the fundamentals first. If you're already doing most things right and want to address the cellular ageing aspect, NMN at a meaningful dose is a legitimate addition.
Cost and Long-Term Use
NMN is not cheap at therapeutic doses. The 500mg daily dose from Charava runs to approximately ยฃ60โ80 per month. This is the main limiting factor for most people.
For those who want to stack the longevity protocol properly: NMN + resveratrol + TMG is the combination used in the most relevant human research. Charava makes all three, which simplifies the stack.
Check Charava's NMN and longevity range โ
500mg of properly tested NMN daily with TMG cofactor for 90 days, judged on HRV, HbA1c and energy rather than acute feel. Expect modest, slow, mechanism-led shifts โ not a lifespan miracle.
This review is based on personal experience and does not constitute medical advice. NMN supplements are not intended to diagnose, treat, or cure any disease. Individual results will vary.
