Not approved for human useHuman evidence

NAD+ and precursors

Also referred to as Nicotinamide adenine dinucleotide, NMN, NR, Nicotinamide riboside

Included because it appears constantly alongside peptides. Oral precursors reliably raise blood NAD+. Downstream functional benefits have been inconsistent.

Molecule class: Coenzyme and its biosynthetic precursors (not a peptide)
Category: Longevity
Last evidence review: 2026-08-23

Compare this compound Check interactions Solution calculator

Human studies

Animal / in vitro

Graded claims

—

Participants

Mechanism

What is being studied

NAD+ is a redox coenzyme and a substrate for sirtuins and PARPs. Precursors raise circulating NAD+ concentrations.

Evidence

Claims, graded individually

Each statement below carries its own evidence level, its own confidence rating, and its own account of what remains unestablished. A compound does not have a single grade.

Aging & Longevity Research

BModerateHigh confidenceHuman evidence

Oral NAD+ precursors reliably raise blood NAD+ concentration in randomised human trials.

What is not established

Raising a biomarker is not the same as improving an outcome.

Supporting sources (1)

Randomised controlled trialHumanIdentifier pending verification

NAD+ precursor supplementation in human trials

Multiple · Various metabolism and ageing journals · 2022

Population: Healthy middle-aged and older adults across several small trials
Endpoint: Blood NAD+ concentration, physical function, metabolic markers
Route: Oral in most trials; intravenous NAD+ is far less studied
Quantity as reported: Reported per trial
Frequency: Daily
Duration: 12 weeks

Result. Trials consistently show that oral precursors raise blood NAD+ concentration. Downstream functional and clinical benefits have been inconsistent.

Adverse events. Generally well tolerated in the oral trials at studied quantities.

Limitations. Raising a biomarker is not the same as improving an outcome. Intravenous NAD+ is much less studied than oral precursors, and the two should not be treated as interchangeable.

Search PubMed for this literature →

Last evidence review: 2026-08-23

Aging & Longevity Research

XInsufficient / conflictingLow confidenceHuman evidence

Whether raising NAD+ produces functional or clinical benefit in healthy adults is not established.

What is not established

Functional endpoints have been inconsistent across small, short trials.

Supporting sources (1)

Randomised controlled trialHumanIdentifier pending verification

NAD+ precursor supplementation in human trials

Multiple · Various metabolism and ageing journals · 2022

Population: Healthy middle-aged and older adults across several small trials
Endpoint: Blood NAD+ concentration, physical function, metabolic markers
Route: Oral in most trials; intravenous NAD+ is far less studied
Quantity as reported: Reported per trial
Frequency: Daily
Duration: 12 weeks

Result. Trials consistently show that oral precursors raise blood NAD+ concentration. Downstream functional and clinical benefits have been inconsistent.

Adverse events. Generally well tolerated in the oral trials at studied quantities.

Limitations. Raising a biomarker is not the same as improving an outcome. Intravenous NAD+ is much less studied than oral precursors, and the two should not be treated as interchangeable.

Search PubMed for this literature →

Last evidence review: 2026-08-23

Human evidence

1 human study catalogued

Human and non-human evidence are kept strictly separate. They are never pooled, averaged, or presented as a single body of support.

Randomised controlled trialHumanIdentifier pending verification

NAD+ precursor supplementation in human trials

Multiple · Various metabolism and ageing journals · 2022

Population: Healthy middle-aged and older adults across several small trials
Endpoint: Blood NAD+ concentration, physical function, metabolic markers
Route: Oral in most trials; intravenous NAD+ is far less studied
Quantity as reported: Reported per trial
Frequency: Daily
Duration: 12 weeks

Result. Trials consistently show that oral precursors raise blood NAD+ concentration. Downstream functional and clinical benefits have been inconsistent.

Adverse events. Generally well tolerated in the oral trials at studied quantities.

Limitations. Raising a biomarker is not the same as improving an outcome. Intravenous NAD+ is much less studied than oral precursors, and the two should not be treated as interchangeable.

Search PubMed for this literature →

Pharmacology

Reported parameters

Half-life

Not characterised

Varies substantially by precursor and route.

Routes studied

Oral
Intravenous
Subcutaneous

Evidence from one route does not transfer to another. Topical, oral, and injected administration can produce entirely different exposure from the same quantity.

Regulatory status

Oral precursors are marketed as dietary supplements. Intravenous NAD+ preparations are not approved and are far less studied. The regulatory status of NMN specifically has been contested.

Storage as documented

Per the individual supplement or preparation.

Safety

Signals reported in the literature

This lists what has been reported. It is not a complete safety profile, and for several compounds in this catalogue no systematic safety surveillance exists at all.

Oral precursors generally well tolerated at studied quantities
Intravenous administration is associated with infusion reactions and is much less studied

Interactions

Register entries involving this compound

nad-plus ↔ semaglutide

No interaction meeting our evidence criteria is currently documented between these compounds.

Limitations. Absence of evidence is not evidence of safety. This pair has not been the subject of a dedicated interaction study.

Open the full interaction explorer →

Limitations

What the evidence cannot tell you

Given as much prominence as the findings, because for most compounds in this category it is the more important half.

Raising a biomarker is not the same as improving an outcome
Oral precursors and intravenous NAD+ are not interchangeable
Trials are small and short relative to the claims made

Reference

Evidence grading key

AStrong

Multiple high-quality human trials, or strong systematic-review or meta-analytic evidence.

BModerate

Human controlled evidence exists, but replication or sample size is limited.

CPreliminary

Small human studies, observational evidence, or early-phase clinical work.

DPreclinical

Predominantly animal or in-vitro evidence. No adequate human outcome data.

EMechanistic

Biological plausibility or mechanistic reasoning without adequate outcome evidence.

XInsufficient / conflicting

Evidence is absent, irreconcilable, or too weak to support any directional statement.

Other compounds studied in the same research areas

Epitalon

Widely marketed for longevity. The evidence originates almost entirely from a single research programme and has not been independently replicated.

MOTS-c

An interesting endogenous signalling peptide with genuine mechanistic literature and essentially no human outcome evidence.

Elamipretide (SS-31)

A genuinely investigational compound with registered clinical trials and a development history that includes missed primary endpoints. A useful case study in conflicting evidence.