NMN (nicotinamide mononucleotide)
Summary
NMN raised blood NAD in a 60-day trial, and at 250–2,000 mg/day for up to 24 weeks it was well tolerated. Pooled trials found no clear benefit for blood sugar or cholesterol; gait speed and walking distance improved modestly in some small trials. FDA confirmed in 2025 that NMN can be sold as a supplement.
Key facts
- Beta-NMN capsules, tablets and powders[1]
- No head-to-head human data between NMN products in our sources[2]
- Blood NAD ↑ (C); fasting glucose, insulin, HbA1c and lipids: no significant effect (C); gait speed ↑ and ALT ↓ in middle-aged and older adults (C); six-minute walk ↑ in one 60-day trial (C)[4][2][3]
- A 2026 meta-analysis of 15 trials found no increase in adverse events or liver enzymes with short-term use; long-term safety is unknown[5]
- FDA said NMN was excluded from supplements in 2022, then reversed this on September 29, 2025, concluding NMN is not excluded from the dietary-supplement definition[1]
- 3 graded human outcomes on this page
- October 8, 2026
How it works
ProposedNMN availability is a rate-limiting factor in NAD+ synthesis in mammals, and in rodents obesity and aging impair NAD+ biosynthesis (animal data; proposed relevance to humans). Oral NMN at 300–900 mg/day raised blood NAD in people (established).[6][4]
What the human research says
Human trials only, one row per outcome. The form column shows what each trial actually tested. Grades follow our evidence-grading policy.
At a glance: strongest evidence per outcome
| Outcome | Grade | Effect | Strongest evidence | Rows |
|---|---|---|---|---|
| Healthy aging | Grade C | Improved | Meta-analysis · n = 412 · 2025 | 2 rows |
| Metabolic | Grade C | No effect | Meta-analysis · n = 342 · 2024 | 1 row |
Every graded row
| Outcome | Effect | Grade | Best evidence | PMID |
|---|---|---|---|---|
| Gait speed and liver enzymes in middle-aged and older adults | Improved | Grade C | Meta-analysis · n = 412 · 2025 Middle-aged and older adults in 9 randomized controlled trials Form: NMN · Dose: Varied; small doses had the largest effect on HOMA-IR in subgroups · Duration: Varied across trials NMN improved gait speed (SMD 0.34) and lowered ALT (SMD -0.29). | 39185644 (opens PubMed)Source [3] |
| Fasting glucose, insulin, HbA1c and lipids | No effect | Grade C | Meta-analysis · n = 342 · 2024 Middle-aged and older adults (49% women, mainly without diabetes) in 8 randomized controlled trials Form: NMN · Dose: 250–2,000 mg/day · Duration: 14 days to 12 weeks NMN showed no significant benefit on fasting glucose, fasting insulin, HbA1c, HOMA-IR or the lipid profile. | 39531138 (opens PubMed)Source [2] |
| Blood NAD and six-minute walking distance | Improved | Grade C | RCT · n = 80 · 2023 Healthy middle-aged adults Form: NMN vs placebo · Dose: 300, 600 or 900 mg/day · Duration: 60 days Blood NAD rose in all NMN groups versus placebo. Six-minute walking distance increased more with all doses than placebo, most with 600 and 900 mg. HOMA-IR did not differ from placebo, and NMN was well tolerated. | 36482258 (opens PubMed)Source [4] |
Forms
| Form | Elemental % | Absorption (human data) | GI tolerance | Studied for |
|---|---|---|---|---|
| Beta-NMN capsules, tablets or powder | 100%[1] | Raised blood NAD at 300–900 mg/day over 60 days.[4] | No increase in adverse events or liver enzymes versus placebo across short-term trials.[5] | Metabolic markers, physical function, NAD levels |
Compound weight → elemental active
500 mg beta-nmn capsules, tablets or powder ≈ 500 mg elemental active
Studied doses
Doses studied in human trials ranged from 250 to 2,000 mg of NMN a day for 14 days to 24 weeks. One manufacturer's notification to FDA set its intended amount at no more than 400 mg a day.[5][1]
Interactions
Published interactions only: each row cites a source. No row means none was found in our sources, not that a combination is safe.
None found in our sources.
Who should be careful
- Long-term use
- Trials lasted 24 weeks at most; long-term safety has not been established.[5]
- Regulatory note
- FDA's acknowledgement of an NMN notification is procedural and is not a finding that NMN or products containing it are safe.[1]
- Before you start
- Talk to your pharmacist or clinician before adding this supplement, especially if you take prescription medicines, are pregnant or breastfeeding, or have a chronic health condition.[5]
Talk to your pharmacist or clinician before starting a supplement, especially if you take prescription medicines.
Articles about NMN (nicotinamide mononucleotide)
Plain-English answers to common questions, built on the evidence above.
Frequently asked questions
Does NMN raise NAD+ levels?
Yes. In a 60-day trial of 80 middle-aged adults, 300, 600 and 900 mg/day all raised blood NAD versus placebo.[4]
Does NMN help blood sugar?
A 2024 meta-analysis of 8 trials (342 adults) found no significant effect on fasting glucose, insulin, HbA1c or lipids. One 10-week trial in postmenopausal women with prediabetes found better muscle insulin sensitivity.[2][6]
Is NMN legal to sell as a supplement?
FDA took the position in 2022 that NMN was excluded from supplements because it had been investigated as a drug. On September 29, 2025, FDA reversed this and concluded NMN is not excluded from the dietary-supplement definition.[1]
Is NMN safe?
Across 15 trials using 250–2,000 mg/day for up to 24 weeks, NMN did not increase adverse events or liver enzymes. Longer-term safety data are lacking.[5]
Sources
- [1]Letter on NDIN 1259 (beta-nicotinamide mononucleotide), December 2, 2025. U.S. Food and Drug Administration, 2025. guideline
- [2]Effects of Nicotinamide Mononucleotide on Glucose and Lipid Metabolism in Adults: A Systematic Review and Meta-analysis of Randomised Controlled Trials.. Curr Diab Rep, 2024. meta-analysis
- [3]Effects of Nicotinamide Mononucleotide Supplementation on Muscle and Liver Functions Among the Middle-aged and Elderly: A Systematic Review and Meta-analysis of Randomized Controlled Trials.. Curr Pharm Biotechnol, 2025. meta-analysis
- [4]The efficacy and safety of β-nicotinamide mononucleotide (NMN) supplementation in healthy middle-aged adults: a randomized, multicenter, double-blind, placebo-controlled, parallel-group, dose-dependent clinical trial.. Geroscience, 2023. RCT
- [5]Safety and Metabolism-Related Outcomes of Oral Nicotinamide Mononucleotide Supplementation in Adults: A Systematic Review and Meta-Analysis.. Nutrients, 2026. meta-analysis
- [6]Nicotinamide mononucleotide increases muscle insulin sensitivity in prediabetic women.. Science, 2021. RCT
What changed
- First draft. Every evidence-row PMID checked with NCBI E-utilities (esummary + efetch abstract) and re-read in an independent adversarial pass.