NMN (nicotinamide mononucleotide): research, side effects and dosage in studies

In short

NMN, or nicotinamide mononucleotide, is an NAD+ precursor and not a peptide. In small trials it raised blood NAD levels and was well tolerated in the short term [1]A, but benefit for ageing has not been shown [5]. In the EU it is an unauthorised novel food [6]regulator.

• NMN is a nucleotide from which the body makes the coenzyme NAD+ [1]A.
• In small randomised trials NMN raised blood NAD levels [2, 3]A, but in a meta-analysis of 15 trials it did not affect blood glucose or blood lipids [4]A.
• Some of the trials were funded by NMN manufacturers or suppliers [2, 3]A.
• In short trials NMN did not increase harms, but long-term safety is unknown [4]A.
• In the EU NMN is listed as a novel food that is not yet authorised, and an unauthorised novel food may not be placed on the market [6, 7]regulator.

What is NMN?

NMN, or nicotinamide mononucleotide, is not a peptide, meaning it is not made of amino acids. It is a nucleotide from which the body makes NAD+, and the availability of NMN limits NAD+ production in mammals [1]A.

NAD+ is a cellular coenzyme whose levels decline with age. This has given rise to products aimed at "boosting" NAD+, such as the precursors NMN and nicotinamide riboside (NR) [5]. In humans NMN has mainly been studied taken by mouth [4]A [5].

NAD+, which is also given as infusions, has its own page: NAD+. All substances: Peptides A-Z.

Evidence at a glance

Each cell gives the kind of study and its source. The letter is the evidence level, not the result.

"-" = no such study is known.

What is NMN studied for?

NMN is studied for ageing and metabolism, and none of these is an approved use: NMN is not a medicine and not an authorised novel food in the EU [6, 8]regulator.

• Insulin sensitivity and blood glucose: a trial in women with prediabetes [1]A and a meta-analysis of 15 trials [4]A.
• Physical function: walking and grip strength in middle-aged and older adults [2, 3]A.
• Ageing and wellness: a systematic review of NAD+ precursors [5].

Claims online. The claim that NMN slows ageing is not based on research: according to the review, raising NAD levels has a clear biological effect, but benefit for ageing or wellness has not been shown [5].

How does NMN work?

NMN is converted into NAD+ in the body [1]A. Taken by mouth, it raised blood NAD levels in several trials [2, 3]A.

A rise in blood NAD does not mean the same happens in tissues or that metabolism improves. In the trial in women with prediabetes, muscle NAD+ content did not change [1]A, and in the meta-analysis NMN did not affect blood glucose or lipids [4]A.

Has NMN been studied in humans?

Yes. There are at least 15 randomised trials, but they are small and short [4]A [5]. The main ones are below.

Human studies

• Insulin sensitivity (2021). A 10-week randomised, double-blind trial included 25 postmenopausal women with prediabetes and overweight or obesity. In the NMN group (13 women), muscle insulin sensitivity was 25% (± 7%) higher at the end than at the start, but in the placebo group (12 women) it did not change. Muscle NAD+ content did not change in either group [1]A.
• Healthy middle-aged adults (2023). In a 60-day trial, 80 healthy middle-aged adults received placebo or one of three NMN doses. Blood NAD rose in all NMN groups, and six-minute walk distance increased more than with placebo. HOMA-IR, a measure of insulin resistance, did not differ from placebo [2]A.
• Older men (2022). A 12-week trial randomised 42 healthy men aged 65 or over. NMN raised blood NAD+. Improvements in walking speed and left-hand grip strength were only nominally significant. NMN had no effect on body composition. Data from some participants had to be excluded, which weakened the comparability of the groups [3]A.
• Meta-analysis (2026). Across 15 randomised trials, NMN had no significant effect on body weight, body mass index, fasting glucose, HbA1c, blood lipids or systolic blood pressure. Diastolic blood pressure fell slightly [4]A.

For NMN given into a vein, the review found only one non-randomised study, which mainly provided short-term safety data [5].

Who studies NMN?

Some key trials were funded by NMN manufacturers or suppliers. The middle-aged trial was fully funded by Aba Chemicals and Abinopharm, the companies that developed the NMN product [2]A. The trial in older men was funded by Mitsubishi Corporation Life Sciences, which supplied the NMN [3]A. According to the disclosures of the insulin sensitivity trial, one author is an inventor on an NMN-related patent application and another receives a share of patent licensing fees [1]A.

Who wrote this page: the editorial team

This page was written by the Molecular Recovery editorial team. The draft was made with the help of AI, and the claims were checked against the sources (AI policy). The page has not been medically reviewed. How we work: About us.

What are the side effects of NMN?

In short trials NMN did not increase harms, but there are no data on long-term safety [4]A.

What users report. In the Reddit accounts we compiled (not research), 36 of 82 people (44%) reported some harm, most often: anxiety or restlessness (10, 12%), insomnia (9, 11%) and rash or acne (5, 6%). People tend to post when something goes wrong, so this share does not tell how common harms are. NMN is not a peptide but an NAD+ precursor sold as a food supplement, and almost everyone took it by mouth. The benefits reported are feelings such as energy and focus. 41 people (50%) used other substances or supplements at the same time. The harms in detail: NMN user experiences.

What the trials found

• In the insulin sensitivity trial no adverse events and no abnormal blood test results were reported [1]A.
• In the middle-aged trial no safety issues were found at doses up to 900 mg a day [2]A, and in older men NMN was well tolerated [3]A.
• According to the meta-analysis, NMN did not increase adverse events, serious adverse events or withdrawals due to adverse events, and it did not raise liver enzymes (ALT, AST) [4]A.

What has not been studied

The individual trials described on this page were small, with 25-80 participants, and the meta-analysis trials lasted 24 weeks at most, so they cannot reveal rare or long-term harms [1, 2, 4]A. The authors say long-term safety needs to be confirmed in larger and longer trials [4]A. More: Side effects and safety.

Interactions and who lacks data

Interactions with other medicines have not been studied. The trials were done in adults [4]A, so there are no data for children, pregnancy or breastfeeding.

What speaks against it and what is unknown

Higher NAD levels have not consistently shown up as health effects [4]A [5].

Contrary evidence

• In the meta-analysis NMN had no significant effect on blood glucose, HbA1c or blood lipids [4]A.
• In the insulin sensitivity trial muscle NAD+ content did not change [1]A.
• In middle-aged adults HOMA-IR did not differ from placebo [2]A.
• The improvements in older men were only nominally significant, and some data were excluded [3]A.

What the evidence does not support

• "NMN is a peptide": it is not. NMN is a nucleotide from which the body makes NAD+ [1]A.
• "NMN slows ageing": this has not been shown [5].
• "When blood NAD rises, metabolism improves": not necessarily [1, 4]A.
• "NMN is an authorised food supplement in the EU": the EU novel food catalogue lists it as a novel food that is not yet authorised [6]regulator.

It is not known whether NMN has clinical benefit: larger and longer randomised trials measuring meaningful health outcomes are needed [5]. According to the authors, the improvements in walking speed and grip strength in older men need to be confirmed in larger trials [3]A.

NMN dosage in studies

NMN has no approved dosage, because it is not a medicine and not an authorised novel food [6, 8]regulator. Below are the oral amounts used in studies. They are not recommendations.

What the numbers do not tell you. Long-term use was not studied in these trials [4]A, and the trials used NMN supplied by manufacturers [1, 2, 3]A. More: NMN doses in studies. The calculator has no NMN preset, because in the trials NMN was taken by mouth.

NMN vs NAD+: what is the difference?

NMN is an NAD+ precursor from which the body makes NAD+ [1]A. In humans NMN has mainly been studied taken by mouth, whereas NAD+ is also offered as infusions [4]A [5].

• Evidence: NMN has several small randomised trials and a meta-analysis [1, 2, 3, 4]A. There is little research on NAD+ or NMN given into a vein [5].
• Another precursor: nicotinamide riboside (NR) is also an NAD+ precursor [5].

More: NAD+: research and side effects.

Is NMN legal in Finland?

NMN may not be sold in the EU as a food or food supplement, because it has no novel food authorisation [6, 7]regulator. The ban concerns placing the product on the market, that is, selling it. The site's law page covers medicines (Peptides and the law in Finland); for ordering a food supplement online, the Finnish Food Authority's advice is summarised below [9]regulator.

• Novel food. A novel food is a food or ingredient that was not used for human consumption to a significant degree in the EU before 15 May 1997, and placing it on the market requires an authorisation [7]regulator.
• Status of NMN. The EU novel food catalogue lists NMN (purity 95-99%) as a novel food that is not yet authorised. The entry is based on the conclusion of the Czech authority in the EU consultation procedure [6]regulator.
• Food control. According to the Finnish Food Authority, an unauthorised novel food found in food control leads to a request for clarification and usually to removal of the product from the market [7]regulator.
• Applications under review. In May 2026 the European Food Safety Authority (EFSA) assessed one manufacturer's NMN as safe as a food supplement for adults at up to 300 mg a day (not for pregnant or breastfeeding women). The opinion is not an authorisation: the European Commission and the Member States decide on that [10]regulator.
• Medicine. There is no centrally authorised medicine containing NMN in the EU [8]regulator.

This is not legal advice. Disclaimer.

How is an NMN product assessed?

Trial results do not tell what a product on the market contains or how pure it is, because the trials used NMN supplied by manufacturers [1, 2, 3]A.

According to the Finnish Food Authority, buying a food supplement online from an unknown seller can be a risk, and when ordering online you should check whether the product may be regarded as a medicine in Finland [9]regulator. Reading a certificate of analysis (COA): How to read a COA and check a test result.

FAQ

Read the research yourself: sources

Every source opens the original publication or the regulator's page. The level shows what the source itself reports.

1. Yoshino M, Yoshino J, Kayser BD, et al. Nicotinamide mononucleotide increases muscle insulin sensitivity in prediabetic women. Science. 2021;372(6547):1224-1229. PMID 33888596 A
2. Yi L, Maier AB, Tao R, et al. The efficacy and safety of beta-nicotinamide mononucleotide (NMN) supplementation in healthy middle-aged adults: a randomized, multicenter, double-blind, placebo-controlled, parallel-group, dose-dependent clinical trial. GeroScience. 2023;45(1):29-43. PMID 36482258 A
3. Igarashi M, Nakagawa-Nagahama Y, Miura M, et al. Chronic nicotinamide mononucleotide supplementation elevates blood nicotinamide adenine dinucleotide levels and alters muscle function in healthy older men. NPJ Aging. 2022;8(1):5. PMID 35927255 A
4. Yang W, Huang J, Tang Z, et al. Safety and Metabolism-Related Outcomes of Oral Nicotinamide Mononucleotide Supplementation in Adults: A Systematic Review and Meta-Analysis. Nutrients. 2026;18(14):2251. PMID 42514320 A
5. Gallagher C, Emmanuel OO. NAD+ supplementation for anti-aging and wellness: A PRISMA-guided systematic review of preclinical and clinical evidence. Ageing Res Rev. 2026;116:103057. PMID 41655607 (review)
6. European Commission. EU Novel Food status catalogue, entry "Nicotinamide mononucleotide (purity is 95-99 %)" (POL-NF-00540), status as of 12 Oct 2026: not yet authorised novel food. European Commission regulator
7. Ruokavirasto (Finnish Food Authority). Uuselintarvikkeet ja uudet prosessit (novel foods and new processes). Ruokavirasto regulator
8. European Medicines Agency. Medicine data (centrally authorised medicines, data set of 15 Sep 2026): no product with NAD+, nicotinamide riboside or nicotinamide mononucleotide as active substance. EMA regulator
9. Ruokavirasto (Finnish Food Authority). Ravintolisät: neuvoja kuluttajille (food supplements: advice for consumers). Ruokavirasto regulator
10. EFSA Panel on Nutrition, Novel Foods and Food Allergens (NDA). Safety of beta-nicotinamide mononucleotide (β-NMN) pursuant to Regulation (EU) 2015/2283 and the bioavailability of nicotinamide from this source in the context of Directive 2002/46/EC. EFSA Journal. 2026;24(5):e10007 (11 May 2026). EFSA Journal regulator

Research sources checked 12 Oct 2026. Regulator and registry sources checked 15 Sep to 13 Oct 2026.

Evidence levels: A = randomised human trial or meta-analysis · B = observational human study or case series · C = animal study · D = cell or laboratory study · E = not peer-reviewed · regulator = a regulator's assessment or decision, not research evidence. The marker official means official product information (summary of product characteristics or label); it is not research evidence. For a review, the level shows what kind of research the statement rests on. No level: statements that something has not been studied, reviews' interpretations, named hypotheses and the general rules in our certificate-of-analysis guide.

Content is general information about research, not medical advice. If you have symptoms, contact a healthcare professional.