Emerging therapy
NAD+ (direct supplementation)
Beyond the precursor supplements (NMN, NR), a market has grown for taking NAD+ itself — orally, and as intravenous drips sold by wellness clinics at hundreds of pounds a session. The molecule's biology is central to ageing research; the evidence for administering it directly is far thinner than the clinic menus imply.
Quick verdict
A small pilot study shows a six-hour NAD+ infusion changes the plasma NAD+ metabolome — pharmacology, not benefit. No controlled trial shows any health outcome from oral or intravenous NAD+, and IV drips are an unregulated wellness service, not a licensed therapy.
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 |
|---|---|---|
| Intravenous NAD+ increases NAD+ availability in the body | Surrogate biomarker | Early |
| Extends human lifespan or slows ageing | Lifespan | Insufficient |
Intravenous NAD+ increases NAD+ availability in the body
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.
An 11-person pilot study infused NAD+ over six hours and tracked the plasma and urine metabolome, showing the molecule is taken up and metabolised — with most of the change appearing only after two hours. That is a pharmacokinetic observation, several steps removed from any benefit.
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. Non-randomised trial with 11 participants.
- Human research volume. 1 human study, 11 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. Eleven participants, no control arm for outcomes, no health endpoint of any kind.
| Study | Design | Population | Finding |
|---|---|---|---|
| [1]A Pilot Study Investigating Changes in the Human Plasma and Urine NAD+ Metabolom…Frontiers in aging neuroscience · 2019 · PMID 31572171 | Non-randomised trialHuman | 11 participantsHealthy participants | Supports the claimPilot: 6-hour IV NAD+ infusion altered plasma/urine NAD+ metabolome in 11 healthy men. |
Extends human lifespan or slows ageing
Insufficient evidenceOutcome measured: Lifespan — Death from any cause was measured.
No trial of direct NAD+ administration has measured any ageing-related outcome. The clinic marketing extrapolates from the biology of NAD+ decline, not from tests of the drip being sold.
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. Entirely untested.
Human evidence
1 study in people.
- [1]Non-randomised trial · 11 participants
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
Rapid NAD+ infusions commonly cause flushing, nausea and chest pressure, which clinics manage by slowing the drip. No controlled long-term safety data exist for repeated administration.
Regulatory and availability. IV NAD+ is offered as a wellness service outside medicines licensing; no regulator has assessed the treatment claims made for it.
The ledger
Grade history
22 August 2026
First published appraisal of this claim. Study links added: PMID 31572171.
22 August 2026
First published appraisal of this claim.
Falsifiability
What would change our view
Any randomised trial of oral or IV NAD+ against a health endpoint — none has been published.
Check everything
Sources
Every citation links to its PubMed record. Bibliographic details are retrieved from PubMed, not written by us.
- [1]A Pilot Study Investigating Changes in the Human Plasma and Urine NAD+ Metabolome During a 6 Hour Intravenous Infusion of NAD Grant R et al.. Frontiers in aging neuroscience. 2019. PMID 31572171 · doi:10.3389/fnagi.2019.00257