Evidence File 035 · Nicotinamide Riboside · Method v0.14 of 4 claims researched

Nicotinamide RibosideNR chloride · 4 claims

Better pharmacokinetic evidence than NMN, the same problem downstream: the levels rise and the outcomes do not follow.

4Claims scored

6Sources

100–1000 mgStudied dose

Jul 26Reviewed

Claim 01

Raises NAD+ levels in a dose-dependent way

6.0/10

Moderate·Clear pharmacokinetics · measured in tissue

A single 1,000 mg oral dose of NR raised peripheral blood mononuclear cell NAD+ 2.7-fold in a healthy adult. Daily 1,000 mg over seven days produced sustained elevations of 2 to 15-fold versus baseline, measurable within roughly four hours of the first dose.

Given to 12 healthy men and women at 100, 300 and 1,000 mg with seven-day washouts, increases were dose-dependent, appeared within 8 hours and were still elevated 23 hours later. No adverse events at the highest dose.

Orally administered NR does what it says on the tin at the level of pharmacokinetics. That is not in dispute.

The working

5Quantity

6Quality

8Consistency

4Directness

(5 × 0.25) + (6 × 0.35) + (8 × 0.25) + (4 × 0.15) = 6.0
The strongest part of the NAD precursor case, and again a marker rather than an outcome.

PKTrammell SAJ, et al. NR bioavailability data, as summarised in the NCT03743636 trial protocol Single-dose and 7-day dosing in peripheral blood mononuclear cells

Claim 02

Improves muscle mass and strength in older adults

4.7/10

Emerging·Reviewers’ own word: inconclusive

A systematic review and random-effects meta-analysis of randomised trials in adults aged 60 and over examined NR and NMN against skeletal muscle index, handgrip strength and gait speed. The conclusion was that evidence on their effects in older adults remains inconclusive.

The preclinical case is strong — NR activates SIRT1 in skeletal muscle in animal models and increases expression of genes governing mitochondrial activity. The human sarcopenia outcomes have not followed.

The working

4Quantity

5Quality

3Consistency

8Directness

(4 × 0.25) + (5 × 0.35) + (3 × 0.25) + (8 × 0.15) = 4.7
Scored on the reviewers’ explicit conclusion rather than on any individual positive trial.

MetaThe effect of nicotinamide mononucleotide and riboside on skeletal muscle mass and function: systematic review and meta-analysis Adults 60+, SMI, handgrip strength, gait speed

Claim 03

Is well tolerated at supplemental doses

5.7/10

Emerging·No adverse events at 1,000 mg · short exposure

No adverse events were associated with the 1,000 mg dose in the dose-ranging study. Trials in heart failure have escalated to 1,000 mg twice daily without reported safety stops.

The honest caveat is that most NR safety data comes from studies lasting days to a few months, in small numbers of people, for a product marketed for indefinite daily use.

The working

4Quantity

5Quality

7Consistency

8Directness

(4 × 0.25) + (5 × 0.35) + (7 × 0.25) + (8 × 0.15) = 5.7
Consistent across the dosing studies, but exposure durations are short and populations small.

PKNR dose-ranging safety data No adverse events at 1,000 mg
RCTMechanistic studies of nicotinamide riboside in human heart failure NCT04528004 · dose escalation to 1,000 mg twice daily

Claim 04

The human results match the animal literature

2.8/10

Evidence against·Strong preclinical case · weak translation

In mice, NAD precursor and resveratrol work produced larger and more abundant mitochondria in non-oxidative muscle fibres after 15 weeks, increased mitochondrial enzyme activity, and animals that ran further on treadmills.

In humans, NAD levels rise reliably, metabolic outcomes largely do not move, and sarcopenia outcomes are inconclusive. This is the standard pattern for longevity compounds and it is the single most useful thing to know before buying any of them.

The working

1Quantity

3Quality

1Consistency

8Directness

(1 × 0.25) + (3 × 0.35) + (1 × 0.25) + (8 × 0.15) = 2.8
Scored as support for the claim. The gap between the rodent findings and the human outcomes is the defining feature of this category.

RevPreclinical rationale as stated in NCT03743636 protocol background SIRT1 activation, mitochondrial gene expression, murine treadmill performance
MetaHuman metabolic outcomes meta-analysis Most clinically relevant outcomes not significantly different

Dosage as studied

Most-studied regimen

100–1000 mg per day

Dose-dependent NAD+ elevation demonstrated across 100, 300 and 1,000 mg. No adverse events at 1,000 mg in the dosing study.

Pharmacokinetics: A single 1,000 mg oral dose raised peripheral blood mononuclear cell NAD+ 2.7-fold. Daily 1,000 mg for seven days gave sustained 2 to 15-fold elevations.
Dose-response: Tested at 100, 300 and 1,000 mg in 12 healthy adults, each separated by seven days. Increases were dose-dependent and measurable within 8 hours.
Safety: No adverse events reported at the 1,000 mg dose in the dose-ranging study.
Under investigation: Randomised trials are running in heart failure and peripheral artery disease, some combining NR with resveratrol.