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NMN (nicotinamide mononucleotide)

Vitamins

What nmn (nicotinamide mononucleotide) may help with

Ranked by how strong the human evidence is — best supported first.

Best supportedCognitive ageingNot enough evidence· 4 sources

Then, in order

About NMN (nicotinamide mononucleotide)

A nucleotide precursor of NAD, one step closer to NAD than nicotinamide riboside. It became a mass-market supplement almost entirely on the strength of mouse studies from a small number of laboratories.

NMN is the clearest example in this catalogue of a supplement whose popularity ran far ahead of its evidence and then collided with regulation. Human trials are few, small and short: they show blood NAD rises, and report scattered findings on walking speed, aerobic capacity and insulin sensitivity that have not been independently replicated. Meanwhile the US FDA concluded in 2022 that NMN is excluded from the dietary supplement definition because it was authorised for investigation as a new drug — a regulatory position that has left the product in limbo and driven much of the market offshore or into grey channels. Anyone buying it should know that both the evidence and the legal status are unsettled.

Sold as
Capsule, Sublingual tablet, Powder, Liposomal preparation
Also known as
Nicotinamide mononucleotide, β-NMN, NAD precursor

Regulation: The US FDA has stated that NMN is excluded from the dietary supplement definition because it was authorised for investigation as a new drug, and has issued warning letters on that basis. Australia has restricted it to prescription status at higher doses. No Tolerable Upper Intake Level exists for NMN, and the 35 mg/day vitamin B3 limit was set for other forms entirely. Availability and legality vary by country and are changing.

What the research used

The amounts, forms and durations published trials of NMN (nicotinamide mononucleotide) actually administered.

These are the amounts published trials administered — not a recommendation, and not a dose to copy. Trial participants were screened, supervised and given a characterised preparation. What is in a retail bottle is frequently not what was studied, and the amount that suits one person is not general advice.

  • Studied for Human trials

    250–1250 mg

    Limited

    Oral capsule, daily · 6–12 weeks

    Small trials, mostly in Japan and China, with fewer than 100 participants each. Blood NAD rises; the clinical findings reported — walking distance, aerobic measures — are isolated and unreplicated.

  • Studied for Typical retail supplement

    250–500 mg

    Not enough

    Capsule or sublingual tablet

    Independent testing of NMN products has repeatedly found actual content far below label, including products containing essentially none. This is one of the worst-characterised categories on the market.

This is general information about food, not medical advice. It cannot diagnose, treat or replace guidance from a clinician who knows your history.

When it was taken

Each window says whether a trial compared it against an alternative, or whether it is convention and pharmacology. Most timing advice is the second kind.

None of the timings below were directly compared in a trial. They reflect how the research happened to dose, or what the pharmacology implies — which is not the same as a timing being better.

  • Morning

    Not enough

    Morning dosing is conventional, on the argument that NAD levels follow a daily rhythm. Untested in humans.

    Timing was not directly compared. This reflects convention or how the compound behaves in the body, not a trial showing this window works better.

The evidence in depth

Best supported: Not enough

What each association actually rests on, and the papers behind it. A rating describes the state of the research, not how promising the supplement sounds. How we rate evidence.

Cognitive ageing

Brain & Cognitive Health
Not enough evidence

There is no dependable human evidence that NMN affects cognitive ageing. The longevity claims attached to it are extrapolated from mouse experiments, and mice are not a good model for human ageing interventions.

Not enough evidence. Not enough human research to say anything useful yet.

View the 4 sources

Deep research mode adds each paper’s own conclusion and stated limitations.

Energy metabolism

Energy & Metabolism
Not enough evidence

NMN raises blood NAD in small human trials. Whether that changes energy, fatigue or physical capacity is unresolved: the handful of positive findings come from small unreplicated studies, and no trial has measured a hard outcome.

What may be going on: NMN is converted to NAD by nicotinamide mononucleotide adenylyltransferase. How much intact NMN is absorbed in humans, and whether it must first be converted to nicotinamide riboside in the gut, is still debated.

Not enough evidence. Not enough human research to say anything useful yet.

View the 4 sources

Deep research mode adds each paper’s own conclusion and stated limitations.

Things to know

Interactions, contraindications and dose limits, most serious first. Concentrated extracts interact with medication in ways the whole plant does not, so this section carries more weight here than it does on a food page.

  • Worth knowing

    Regulatory status is unsettled

    The FDA has taken the position that NMN cannot legally be sold as a dietary supplement in the US because it was investigated first as a drug. Products remain widely available online. Buying into that gap means buying from suppliers operating outside the (already minimal) US supplement framework.

  • Worth knowing

    Label accuracy has been repeatedly poor

    Independent analyses have found NMN products containing a fraction of the stated amount, and in some cases none at all. Without third-party certificates of analysis there is no way to know what is in the bottle.

  • Worth knowing

    Unknown long-term safety and unresolved questions about cell proliferation

    Human exposure data run to a few months. As with other NAD precursors, preclinical work raises unresolved questions about whether raising NAD could support the growth of existing tumours. That is a reason for caution in anyone with a cancer history, not a demonstrated harm.

  • Avoid

    Not established in pregnancy or breastfeeding

    There is no safety data in pregnancy or breastfeeding.

Evidence ratings on this page: 2 not enough evidence.

Supplements are sold in the US without pre-market review of efficacy or safety. Nothing on this page is a recommendation to take NMN (nicotinamide mononucleotide), or a dose to follow.