Evidence File 034 · NMN · Method v0.14 of 4 claims researched

NMNNicotinamide mononucleotide · 4 claims

The biomarker moves reliably. Almost nothing downstream of it does, and the trials are far too short to speak to ageing at all.

4Claims scored

5Sources

150–1200 mgStudied dose

Jul 26Reviewed

Claim 01

Raises blood NAD+ levels

6.2/10

Moderate·Reliable · but this is the marker, not the goal

Random-effects meta-analysis across 12 studies and 513 participants found an overall significant effect of NMN in elevating blood NAD levels. This part of the story is solid and consistently replicated.

It is also the entire mechanistic premise of the category. Whether raising the marker produces anything a person would notice is the subject of every claim below.

The working

6Quantity

6Quality

8Consistency

4Directness

(6 × 0.25) + (6 × 0.35) + (8 × 0.25) + (4 × 0.15) = 6.2
Directness scores 4. Nobody takes NMN because they want a number in a blood tube to change.

MetaEfficacy of oral nicotinamide mononucleotide supplementation on glucose and lipid metabolism for adults: systematic review with meta-analysis 12 studies, 513 participants, from 4,049 records · doi 10.1080/10408398.2024.2387324

Claim 02

Improves glucose and lipid metabolism

4.0/10

Weak·Marker up, outcomes flat

The same meta-analysis that confirmed NAD elevation reported the rest plainly: “most of the clinically relevant outcomes were not significantly different between NMN supplementation and control group.” That covers fasting glucose, triglycerides, total cholesterol, LDL-C and HDL-C.

This is the cleanest biomarker-outcome dissociation on the site. The mechanism works exactly as advertised and the consequences do not follow.

The working

2Quantity

5Quality

2Consistency

8Directness

(2 × 0.25) + (5 × 0.35) + (2 × 0.25) + (8 × 0.15) = 4.0
Scored as support for the claim. The trials were adequate; the clinically relevant outcomes did not move.

MetaNMN metabolic outcomes meta-analysis Fasting glucose, triglycerides, total cholesterol, LDL-C, HDL-C

Claim 03

Improves physical performance

4.6/10

Emerging·10 studies · 437 patients · short follow-up

A PRISMA-guided systematic review identified 10 randomised trials covering 437 patients, mean age 58, with a mean follow-up of 9.6 weeks and doses from 150 to 1,200 mg/day.

A separate meta-analysis of NMN and nicotinamide riboside against skeletal muscle index, handgrip strength and gait speed in adults over 60 concluded that evidence on their effects in older adults remains inconclusive.

The working

4Quantity

4Quality

4Consistency

8Directness

(4 × 0.25) + (4 × 0.35) + (4 × 0.25) + (8 × 0.15) = 4.6
A small, short, heterogeneous evidence base. Enough to justify further trials, not enough to justify the marketing.

RevImproved physical performance parameters in patients taking nicotinamide mononucleotide: a systematic review of randomized control trials 10 studies, 437 patients, mean follow-up 9.6 weeks
MetaThe effect of nicotinamide mononucleotide and riboside on skeletal muscle mass and function: systematic review and meta-analysis Adults 60+ · conclusion: inconclusive

Claim 04

Slows biological ageing

2.1/10

Evidence against·No trial has run long enough to test it

The longest NMN trials run twelve weeks. The claim is about decades. There is no human trial in existence with the duration or the endpoints to test it, and the score reflects the absence of evidence rather than evidence of absence.

The mechanistic case rests substantially on rodent work. The next page, on nicotinamide riboside, deals with how well that has translated.

The working

1Quantity

3Quality

2Consistency

2Directness

(1 × 0.25) + (3 × 0.35) + (2 × 0.25) + (2 × 0.15) = 2.1
Directness scores 2. A 4-to-12-week trial measuring handgrip strength cannot address a claim about the rate of ageing, whatever it finds.

RevTrial duration data: mean 9.6 weeks, range 4 to 12 weeks No human trial addresses ageing endpoints

Dosage as studied

Most-studied regimen

150–1200 mg per day in trials

Trial durations ranged from 4 to 12 weeks — a window that cannot address claims about ageing.

Studied range: 150 to 1,200 mg/day across randomised trials.
Trial duration: Mean follow-up 9.6 weeks, range 4 to 12 weeks, in the physical performance review.
Population: Mean age 58 years, range 35 to 81, across 437 participants.
Regulatory note: NMN’s status as a permissible dietary supplement ingredient has been contested in the US. Check current status in your market before relying on availability.