NAD+
Nicotinamide adenine dinucleotide
Essential coenzyme (not a peptide) that declines with age; human benefit of supplementation remains unproven.
Not FDA-approved. Not approved as a drug. Precursors sold as supplements; FDA has disputed NMN's supplement status (2022; later revisited). This page describes research and public discussion; it is not a recommendation to use.
Overview
NAD+ powers hundreds of redox reactions and is a substrate for sirtuins and PARPs. Levels fall with age in tissues. Oral precursors (NR, NMN) raise blood NAD+ in trials but clinical outcome benefits are small or absent so far. IV/injected NAD+ has very limited published data.
Mechanism of action
Electron carrier in metabolism; cofactor for sirtuins, PARPs, and CD38.
Benefits & evidence ratings
Dosing
Doses show what has been studied or discussed — not guidance. Always follow your prescriber.
| Source | Dose | Frequency | Duration | Route |
|---|---|---|---|---|
NR trials B Human clinical data | 250–2,000 mg/day | Daily | 6–12 weeks | Oral |
IV/IM clinic protocols D Anecdotal / community | 250–1,000 mg | Weekly or series | Varies | IV / subcutaneous |
Clinical trials & studies
- RCT2018Chronic nicotinamide riboside supplementation in healthy adults (Nat Commun)
Raised NAD+; no major physiological changes.
- RCT2021NMN increases muscle insulin sensitivity in prediabetic women (Science)
n=25 RCT, 10 weeks.
Safety
Side effects
- IV: chest tightness, nausea, flushing if infused fast
- Oral precursors: generally well tolerated
Contraindications
- Pregnancy (insufficient data)
- Active cancer (theoretical concern about fueling tumors)
Interactions
- Unknown clinically
Long-term safety
Limited data beyond months.
Regulatory status
Unapproved / research
Not approved as a drug. Precursors sold as supplements; FDA has disputed NMN's supplement status (2022; later revisited).
FAQ
Commonly discussed alongside
Listing a combination does not mean it has been studied or is safe.