Nicotinamide mononucleotide (NMN)
Mechanism, regulatory status, and an honest, tiered evidence map.
What it is
Class: NAD⁺ precursor
Also known as: NMN, β-nicotinamide mononucleotide
Relationship to mitochondrial health: Nicotinamide mononucleotide is an NAD+ precursor one step downstream of NR. Like NR, its rationale is restoring age-related NAD+ decline; downstream sirtuin/mitochondrial signalling overlaps mtorix.com.
Regulatory status
Sold as a dietary supplement in several markets; US regulatory status has been contested (FDA has questioned its dietary-supplement eligibility). Not an approved drug and not approved for any anti-aging indication.
Mechanism
Human RCTs show it raises NAD+ and is generally well tolerated; effects on endurance, sleep, arterial stiffness, and lipids are mixed, and a meta-analysis found no glucose/lipid benefit. See /nad-metabolism.
Evidence — Human (randomized, placebo-controlled)
| Species / population | Middle-aged and older adults across several RCTs (e.g. an arterial-stiffness RCT, Sci Rep 2023) and a systematic-review/meta-analysis of RCTs. |
| Exposure, route, schedule | Oral NMN (commonly 250-1000 mg/day) for weeks to months. |
| Comparator / duration | Placebo-controlled, randomized in the individual trials; the meta-analysis pooled RCTs. |
| Endpoint / numeric result | Raises NAD+ metabolites and is well tolerated; an arterial-stiffness signal in one RCT; the meta-analysis found NO significant benefit on glucose or lipid metabolism. |
| What it did NOT establish | Biomarker-grade and mixed; no functional-outcome consistency, no hard clinical outcome, and no lifespan evidence. |
Negative or null findings
- A systematic review/meta-analysis of RCTs found no significant effect of NMN on glucose or lipid metabolism.
- Downstream functional effects (endurance, sleep) are inconsistent across trials; no lifespan endpoint.