There is no established dose of NMN, in the sense that word has for a medicine. A dosing recommendation comes from trials that worked out what amount produces what effect at what risk, and the NMN literature has not done the second half of that — the trials established that blood NAD⁺ rises, and mostly did not establish an outcome to titrate against.
What does exist is a complete, checkable list of the doses researchers administered. That is what this page is. Every figure below is read from the trial’s own abstract, with the population and the duration attached, because a milligram number without those is not information. None of it is a recommendation, and the decision belongs to a clinician who knows your history — the same position we take on injectable NAD⁺ dosing, where the evidence is thinner still.
The doses, trial by trial
100, 250 and 500 mg, single doses. The first human safety study gave single oral doses of 100, 250 and 500 mg of NMN to 10 healthy Japanese men and followed them for five hours. No significant clinical symptoms and no meaningful changes in heart rate, blood pressure, oxygen saturation or body temperature; plasma concentrations of two nicotinamide metabolites rose significantly and dose-dependently [1]. A single dose, in ten people, over five hours.
250 mg daily, 6 to 12 weeks. A placebo-controlled, randomized, double-blind, parallel-group trial gave 250 mg per day to older men for 6 or 12 weeks. It was well tolerated with no significant deleterious effect, raised blood NAD⁺ and its metabolites significantly, and produced what the authors called nominally significant improvements in gait speed and left grip that should be validated in larger studies. Body composition did not change[2].
250 mg daily, 12 weeks. A second trial at the same dose randomized 60 older adults. Its primary outcome, a stepping test, showed no significant difference from placebo at 4 or 12 weeks; blood NAD⁺ rose, and a shorter 4-meter walking time and improved sleep quality scores appeared as secondary outcomes [3].
300, 600 and 900 mg daily, 60 days. The largest dose-ranging trial randomized 80 healthy middle-aged adults to placebo or one of those three doses once daily. Blood NAD rose significantly in every NMN group at day 30 and day 60 against both placebo and baseline (all p ≤ 0.001), with the highest concentrations in the 600 and 900 mg groups, and no safety issues on adverse event monitoring, laboratory or clinical measures [4].
300, 600 and 1,200 mg daily, 6 weeks. A four-arm trial in 48 amateur runners training five or six times a week. Oxygen uptake and power at both ventilatory thresholds increased more than placebo in the medium and high dose groups; VO₂max, oxygen pulse and peak power did not differ in any group [5].
1,250 mg once daily, up to 4 weeks. A randomized, double-blind, placebo-controlled safety study in 31 healthy adults aged 20 to 65. No changes exceeding normal physiological variation across anthropometry, hematology, biochemistry, urine and body composition analyses, and no severe adverse events [6].
1,000 mg twice daily, 28 days. The highest administration in this list. Thirty overweight or obese adults aged 45 and over were randomized 2:1 to two tablets each containing 500 mg of microcrystalline β-NMN, twice daily, or placebo. Adverse events were similar between groups, circulating NAD and its metabolites rose substantially, and body weight, diastolic blood pressure, total cholesterol and LDL cholesterol fell significantly more than placebo — while muscle strength, aerobic capacity, insulin sensitivity and intra-abdominal fat did not differ [7].
The published range, pooled. A 2026 systematic review of 15 randomized trials records doses from 250 to 2,000 mg per day and durations from 14 days to 24 weeks, and found no increase in overall, serious or system-specific adverse events, and no elevation of ALT or AST, across them [8].
What the list tells you, and what it does not
It tells you the studied territory: roughly 250 to 2,000 mg a day, for two weeks to six months, in healthy or overweight adults, with a short-term safety record that holds across the range. Anything outside that has not been tested in people at all, which is worth knowing before you take a product that stacks two servings.
It does not tell you a best dose. Blood NAD⁺ rises more at 600 and 900 mg than at 300 — that much is dose-dependent and consistent. But since the outcomes people actually want were largely absent when measured, there is nothing to optimize the dose against. Higher NAD⁺ is the target only if you accept the biomarker as the goal, and the whole argument of this site is that you should not.
What we will not publish
A milligram-per-kilogram chart, a dose by age or body weight, or a titration schedule. None of those can be derived from the literature above, so producing one would mean inventing it, and invented dosing guidance dressed up as research is the specific failure this category is full of.
Take the list above to a clinician if you want a number that applies to you. Before that, two things are worth settling: whether you want NMN or NR — the NR trials used different doses and have a longer record — and what your chosen product costs per gram, which the cost calculator and price comparison turn into a figure you can line up across sellers. And read what is known about safety before starting anything, at any dose.