Supplement
Nicotinamide mononucleotide (NMN)
NMN is a precursor the body converts into NAD+, a coenzyme central to energy metabolism whose levels decline with age. The commercial case rests on that decline. The scientific question is whether raising NAD+ with an oral supplement produces any measurable health benefit in people — a different question, and one with much less evidence behind it.
Quick verdict
Human trials indicate NMN raises blood NAD+ and is generally well tolerated over the periods studied. Evidence that this translates into meaningful health benefits is early and inconsistent, and no human study has examined lifespan.
The assessment
Claim by claim
Each claim is graded on its own evidence. A grade for one claim says nothing about the others.
| Claim | What was measured | Evidence |
|---|---|---|
| Raises NAD+ levels in blood | Surrogate biomarker | Early |
| Extends human lifespan | Lifespan | Insufficient |
| Improves blood pressure | Surrogate biomarker | Insufficient |
Raises NAD+ levels in blood
Early human evidenceOutcome measured: Surrogate biomarker — A laboratory marker measured as a stand-in for health. A change here does not by itself demonstrate a health benefit.
Human trials have measured increases in blood NAD+ concentration following oral NMN. This is the best-supported claim about NMN — and it is a claim about a laboratory measurement, not about health.
Why this grade — the appraisal in full
One or a small number of small, short or preliminary human studies. Directionally interesting, not yet dependable.
- Strongest study design. Meta-analysis of RCTs.
- Human research volume. 1 human study, 0 participants in total.
- What was measured. Human studies measured surrogate biomarkers only. A change in a marker is not by itself a demonstrated health benefit.
- Replication. The supporting result has not been independently replicated in humans.
Limitations. A rise in circulating NAD+ does not establish that tissue NAD+ rises where it matters, nor that any health outcome improves. This is the distinction the supplement market most often blurs.
| Study | Design | Population | Finding |
|---|---|---|---|
| [1]Safety and Metabolism-Related Outcomes of Oral Nicotinamide Mononucleotide Suppl…Nutrients · 2026 · PMID 42514320 | Meta-analysis of RCTsHuman | Size not recordedMixed population | Supports the claimSystematic review of safety and metabolism-related outcomes of oral NMN in adults. |
Extends human lifespan
Insufficient evidenceOutcome measured: Lifespan — Death from any cause was measured.
No human study has tested whether NMN affects lifespan. Claims of this kind extrapolate from rodent work, where results have themselves been inconsistent.
Why this grade — the appraisal in full
Too little credible research exists to judge the claim either way.
- Available research. No usable studies are linked to this claim.
Limitations. Mouse lifespan findings do not transfer to humans. A supplement that raises a biomarker in people has not thereby been shown to extend their lives.
Improves blood pressure
Insufficient evidenceOutcome measured: Surrogate biomarker — A laboratory marker measured as a stand-in for health. A change here does not by itself demonstrate a health benefit.
A meta-analysis has examined NMN's effect on blood pressure across the available randomised trials.
Why this grade — the appraisal in full
Too little credible research exists to judge the claim either way.
- Strongest study design. Meta-analysis of RCTs.
- Human research volume. 1 human study, 0 participants in total.
- What was measured. Human studies measured surrogate biomarkers only. A change in a marker is not by itself a demonstrated health benefit.
- Replication. The supporting result has not been independently replicated in humans.
Limitations. The underlying trials are small and short. Blood pressure is a well-validated risk marker, but changes measured over weeks in small samples do not establish long-term cardiovascular benefit.
| Study | Design | Population | Finding |
|---|---|---|---|
| [2]Effects of Nicotinamide Mononucleotide Supplementation on Blood Pressure: A Syst…Nutrients · 2026 · PMID 41901064 | Meta-analysis of RCTsHuman | Size not recorded | Direction not yet appraisedSystematic review and meta-analysis of NMN supplementation and blood pressure. |
Human evidence
2 studies in people.
- [1]Meta-analysis of RCTs
- [2]Meta-analysis of RCTs
Animal and laboratory evidence
Shown separately, and never used to support a human claim.
No preclinical study is currently linked on this page.
Before anything else
Safety and interactions
Trials to date report NMN as generally well tolerated at the doses and durations studied, which are mostly weeks to a few months. Long-term safety data in healthy adults is not yet available.
Regulatory and availability. Regulatory status differs by country and has changed in recent years. Check the current position for your jurisdiction before purchase.
The ledger
Grade history
No grade on this page has changed since tracking began. When one moves — a new trial, a retraction, a corrected appraisal — the change is detected automatically and recorded on the public ledger.
Falsifiability
What would change our view
Adequately powered trials measuring clinical or functional outcomes — not NAD+ concentration — over 12 months or more would move this from a mechanistic story to a health claim. Replication of any functional benefit by an independent group would matter most.
Check everything
Sources
Every citation links to its PubMed record. Bibliographic details are retrieved from PubMed, not written by us.
- [1]Safety and Metabolism-Related Outcomes of Oral Nicotinamide Mononucleotide Supplementation in Adults: A Systematic Review and Meta-Analysis Yang W et al.. Nutrients. 2026. PMID 42514320 · doi:10.3390/nu18142251
- [2]Effects of Nicotinamide Mononucleotide Supplementation on Blood Pressure: A Systematic Review and Meta-Analysis of Randomized Controlled Trials Zhang M et al.. Nutrients. 2026. PMID 41901064 · doi:10.3390/nu18060890