NMN (nicotinamide mononucleotide) has become one of the most prominent “longevity” molecules in recent years, often presented as superior to nicotinamide riboside (NR). Yet both serve the same purpose: supplying the body with the building blocks to make NAD+, a coenzyme essential to cells. They differ in three often-confused respects: their pathway through the body, the strength of human trials and their legal status in Europe. Hexagon® sells NR, not NMN: all the more reason to stick to studies and official texts.
Key takeaways
- NR and NMN are two NAD+ precursors. To enter cells, much of the NMN is converted back into NR.
- In the EU, NR chloride has been authorised in food supplements since 2020, at a maximum of 300mg per day in adults.
- NMN received a favourable EFSA opinion in May 2026, but remains unauthorised until the Commission makes a decision.
- Both increase blood NAD+. No clinical benefit is firmly established, and a large one-year NR trial was negative.
NMN and NR: what are they?
Nicotinamide riboside (NR) is a form of vitamin B3: a nicotinamide molecule bound to a sugar, ribose. Nicotinamide mononucleotide (NMN) has the same structure, with an additional phosphate group. Both are natural intermediates in NAD+ metabolism and occur in trace amounts in certain foods.
In supplements, NR is offered as a salt, nicotinamide riboside chloride, and NMN in its beta form (β-NMN). The role of NAD+ and its decline with age are detailed in our article on NAD+ and its functions in the body, and its reduced form in our article on the difference between NAD+ and NADH.
How do NR and NMN become NAD+?
Through the same final pathway. Inside the cell, an enzyme called NRK converts NR into NMN, which is then assembled into NAD+. NR therefore has one additional step to complete, but enters cells easily.
NMN, meanwhile, carries a phosphate group that prevents it from crossing membranes efficiently. Cell experiments with labelled molecules showed that it is first converted into NR outside the cell, then absorbed and converted back into NMN inside. Without the NRK1 enzyme, neither NR nor NMN is used to produce NAD+: their effects therefore overlap considerably. An NMN-specific transporter called Slc12a8 was described in the mouse intestine in 2019, but its role in humans is not established.
The oral route further reduces the differences. In mice, NR and NMN injected into the bloodstream reach several organs intact, but when swallowed, they are largely transformed into nicotinamide in the liver. Nicotinamide, another form of vitamin B3, is itself an NAD+ precursor.
- NR: NR → NMN → NAD+, inside the cell.
- NMN: NMN → NR outside, then NR → NMN → NAD+ inside.
- Orally: a substantial proportion of both becomes nicotinamide before reaching tissues (mouse data).
Do NR and NMN really increase NAD+?
Yes, both do, and more so at higher doses. For NR, a 2019 randomised trial compared 100, 300 and 1,000mg per day for 8 weeks in 140 overweight adults aged 40 to 60. Blood NAD+ increased by 10%, 48% and 139% from baseline, with no serious adverse effect. The trial was funded by the ingredient manufacturer: two of the three authors were employees and the third its scientific adviser.
For NMN, a 2023 trial compared 300, 600 or 900mg per day with placebo for 60 days in 80 healthy middle-aged adults. Blood NAD+ increased in all three NMN groups, with the highest values at 600 and 900mg. The trial was entirely funded by the manufacturer of the NMN tested.
These figures do not identify a winner. The trials differ in measurement method, population and duration; to our knowledge, no large trial has directly compared the two molecules in humans. Other ways to act on NAD+ are presented in our article on ways to increase NAD+.
What do clinical trials show about health?
NMN: a notable finding, a neutral meta-analysis
A widely cited trial published in Science in 2021 involved 25 overweight, prediabetic postmenopausal women: 250mg of NMN per day for 10 weeks increased muscle insulin sensitivity by around 25%. Blood glucose, blood pressure, blood lipids and liver fat did not change.
On a larger scale, the picture is less favourable. A 2025 meta-analysis pooled 8 randomised trials (342 adults, 250 to 2,000mg daily for 2 to 12 weeks): no significant effect of NMN on fasting blood glucose, insulin, glycated haemoglobin, insulin resistance or blood lipids.
NR: more trials, often disappointing results
NR has been tested more often and for longer. The NOPARK trial, published in JAMA in October 2026, followed 410 patients with early-stage Parkinson's disease for one year. At 1,000mg per day, NR did not improve symptoms; the clinical score even progressed slightly less favourably than with placebo (a 2.7-point difference on a 236-point scale). Other NR trials deserve a dedicated article of their own.
NMN or NR: comparison table
| Criterion | NR (chloride) | NMN |
|---|---|---|
| Structure | Nicotinamide + ribose | NR + a phosphate |
| Entry into cells | Direct | Mainly after conversion into NR |
| Blood NAD+ | +48% at 300mg/day (8 weeks) | Increase from 300mg/day (60 days) |
| Doses studied | 100 to 3,000mg/day | 250 to 2,000mg/day |
| Established clinical benefit | None | None |
| Dose considered safe by EFSA | 300mg/day in adults | 300mg/day in adults |
| Pregnancy, breastfeeding | 230mg/day maximum | Excluded from the EFSA opinion |
| EU status | Authorised since 2020 | Unauthorised (favourable EFSA opinion in 2026) |
What is the status of NR and NMN in the European Union?
This is the most concrete difference for consumers in France. A molecule without a significant history of consumption in Europe before May 1997 is a “novel food”: it may only be sold, including as a food supplement, after EFSA assessment and European Commission authorisation.
Nicotinamide riboside chloride: authorised since 2020
Implementing Regulation (EU) 2020/16 authorised nicotinamide riboside chloride in food supplements at a maximum of 300mg per day for adults other than pregnant and breastfeeding women, and 230mg per day for those women. EFSA had considered these doses safe in 2019 and concluded that NR releases bioavailable nicotinamide. In 2021, it joined the official list of vitamin B3 forms permitted in supplements. This is the form used in Hexagon® NAD+ Nicotinamide Riboside Chloride 300mg, at one 300mg capsule per day.
NMN: assessed but not yet authorised
NMN follows the same procedure. In May 2026, EFSA published a favourable opinion on synthetic β-NMN: 300mg per day is considered safe for adults, excluding pregnancy and breastfeeding, and this NMN is a bioavailable source of nicotinamide. In the 90-day rat study, effects on reproductive organs were observed at high doses; EFSA considered the safety margin sufficient.
An EFSA opinion is not an authorisation. Until the Commission adds NMN to the Union list, it cannot legally be marketed as a food supplement in the EU, and any eventual authorisation will cover NMN with precise specifications.
How safe are NR and NMN?
In the short term, both are well tolerated. NR has been tested at up to 3,000mg per day for 4 weeks in 10 patients (versus 10 on placebo), with no moderate or severe adverse effects and a slight initial increase in homocysteine. In NOPARK, serious adverse events were less frequent with NR than placebo (8.3% versus 14.1%). For NMN, 300 to 900mg for 60 days raised no safety concerns.
Two limitations remain: the data cover a few weeks to one year, and tested doses often exceed the 300mg adopted in Europe. At 300mg, NMN provides around 110mg of nicotinamide according to EFSA, and NR chloride around 126mg (molar calculation): well above vitamin B3 requirements, but far below the limit of 900mg per day set for nicotinamide.
Frequently asked questions
Why can NMN be bought online?
Because it is legally sold elsewhere, notably in the United States, where the FDA accepted in 2025 that it could be used in food supplements, and foreign websites ship to France. In the EU, selling an unauthorised novel food remains prohibited, online as in pharmacies, and no European specification yet governs its quality.
Are NMN and NR forms of vitamin B3?
NR chloride is: since Regulation (EU) 2021/418, it appears among the forms of niacin authorised in food supplements. For NMN, EFSA concluded in 2026 that it releases bioavailable nicotinamide, but it does not yet have that legal status. No health claim specific to NR or NMN is authorised in the EU.
Can NMN or NR be found in food?
Yes, in very small amounts. A 2025 analysis measured 0.04 to 13mg of NMN and 0.06 to 1.6mg of NR per 100 g of fresh plant foods, with broccoli and green beans among the richest in NMN. These amounts remain far below the 250 to 1,000mg used in trials.
When during the day should NMN or NR be taken?
Trials have used one or two daily doses without comparing timing. No data show that one time of day is preferable. The simplest approach is to follow the label and not exceed the stated daily dose.
Capsule or powder: does the form matter?
What matters is the amount of NR or NMN actually supplied and its purity. For NR chloride, the European specification requires at least 90% nicotinamide riboside chloride. Choosing between a capsule, softgel or other dosage form is mainly a matter of convenience.
Could NMN or NR promote cancer?
The question is theoretical: tumour cells also need NAD+. Published trials have not reported an increase in cancers, but they are short and were not designed to detect one. If you have a history of cancer or are undergoing treatment, ask your doctor for advice.
Can NMN or NR be combined with resveratrol?
The idea comes from animal research: NAD+ supplies enzymes called sirtuins, which resveratrol has been studied to activate. To our knowledge, no large human trial has demonstrated a benefit of this combination. Also see what is really known about resveratrol.
Conclusion
NMN or NR? Biologically, both lead to NAD+ through converging pathways, and much of what is swallowed becomes nicotinamide. Both increase blood NAD+ in humans, but neither has demonstrated a robust clinical benefit, and NOPARK reminds us that increasing NAD+ is not enough to improve health. In Europe, the real difference is regulatory: nicotinamide riboside chloride is authorised at up to 300mg per day in adults, whereas NMN still awaits authorisation. Whichever molecule is considered, examine the dose, declared form and compliance with this framework.
Sources
- European Commission (2020). Implementing Regulation (EU) 2020/16 of 10 January 2020 authorising the placing on the market of nicotinamide riboside chloride as a novel food. Official Journal of the European Union, 13 January 2020. EUR-Lex
- European Commission (2021). Regulation (EU) 2021/418 of 9 March 2021 amending Directive 2002/46/EC as regards nicotinamide riboside chloride and magnesium citrate malate used in the manufacture of food supplements. EUR-Lex
- EFSA NDA Panel, Turck D et al. (2019). Safety of nicotinamide riboside chloride as a novel food pursuant to Regulation (EU) 2015/2283 and bioavailability of nicotinamide from this source, in the context of Directive 2002/46/EC. EFSA Journal, 17(8), 5775. doi:10.2903/j.efsa.2019.5775
- EFSA NDA Panel, Turck D et al. (2026). Safety of beta-nicotinamide mononucleotide (β-NMN) pursuant the regulation (EU) 2015/2283 and the bioavailability of nicotinamide from this source in the context of Directive 2002/46/EC. EFSA Journal, 24(5), e10007. doi:10.2903/j.efsa.2026.10007
- Ratajczak J et al. (2016). NRK1 controls nicotinamide mononucleotide and nicotinamide riboside metabolism in mammalian cells. Nature Communications, 7, 13103. doi:10.1038/ncomms13103
- Grozio A et al. (2019). Slc12a8 is a nicotinamide mononucleotide transporter. Nature Metabolism, 1(1), 47-57. doi:10.1038/s42255-018-0009-4
- Liu L et al. (2018). Quantitative Analysis of NAD Synthesis-Breakdown Fluxes. Cell Metabolism, 27(5), 1067-1080.e5. doi:10.1016/j.cmet.2018.03.018
- Conze D, Brenner C, Kruger CL (2019). Safety and metabolism of nicotinamide riboside chloride taken for 8 weeks: a double-blind randomised placebo-controlled trial in overweight adults (descriptive title). Scientific Reports, 9, 9772. doi:10.1038/s41598-019-46120-z
- Yi L et al. (2023). 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, 45(1), 29-43. doi:10.1007/s11357-022-00705-1
- Yoshino M et al. (2021). Nicotinamide mononucleotide increases muscle insulin sensitivity in prediabetic women. Science, 372(6547), 1224-1229. doi:10.1126/science.abe9985
- Chen F et al. (2025). Effects of Nicotinamide Mononucleotide on Glucose and Lipid Metabolism in Adults: A Systematic Review and Meta-analysis of Randomised Controlled Trials. Current Diabetes Reports, 25(1), 4. doi:10.1007/s11892-024-01557-z
- Brakedal B et al. (2026). Nicotinamide Riboside for Patients With Early-Stage Parkinson Disease: The NOPARK Randomized Clinical Trial. JAMA, published online 8 October 2026. doi:10.1001/jama.2026.18828
- Berven H et al. (2023). NR-SAFE: a randomized, double-blind safety trial of high dose nicotinamide riboside in Parkinson's disease. Nature Communications, 14, 7793. doi:10.1038/s41467-023-43514-6
- Alegre GFS, Pastore GM (2025). Determination of NAD+ precursors nicotinamide mononucleotide (NMN) and nicotinamide riboside (NR) in plant foods: exploring dietary sources. CyTA – Journal of Food, 23(1), 2458753. doi:10.1080/19476337.2025.2458753
Food supplements do not replace a varied, balanced diet or a healthy lifestyle. Ask a healthcare professional for advice if you are taking medication, pregnant or breastfeeding.
