Guide
How much nicotinamide riboside (NR) should you take a day?
There's no official recommended dose for nicotinamide riboside. Human trials have tested single doses of 100 mg up to daily doses of 2,000 mg, and researchers have proposed — but not finalized — an upper intake level based on that data.
There's no official recommended dose of nicotinamide riboside, unlike vitamins with a government-set intake range. What exists instead is a spread of amounts used in research — from single 100 mg doses up to a sustained 2,000 mg a day in the longest trial — and a proposed, but not finalized, upper intake level based on that data.
What trials have actually tested
The first human trial tested single doses of 100 mg, 300 mg and 1,000 mg and found the blood NAD+ rise was dose-dependent — more NR meant more of a rise, at least within that range, in 12 healthy adults (PMID 27721479). For sustained daily dosing, most trials converged on 1,000 mg a day: an 8-week, placebo-controlled trial of 140 adults tested 100, 300 and 1,000 mg/day and found all three doses safe (PMID 31278280); a 6-week crossover trial gave 30 adults 500 mg twice daily, also 1,000 mg/day total, with no serious adverse events (PMID 29599478). The highest sustained dose in the research reviewed here was 2,000 mg a day — 1,000 mg twice daily — given to 40 obese men for 12 weeks; it was safe, but no more effective than placebo on any outcome the trial measured, including insulin sensitivity and body composition (PMID 29992272). See nicotinamide riboside (NR) benefits: what the research does and doesn't show for what each of these trials actually found beyond safety.
Is there an upper limit?
No regulatory body has finalized an upper intake level (UL) specifically for nicotinamide riboside. The researchers behind the 140-person, 8-week safety trial argue their data — no rise in LDL cholesterol or homocysteine at doses up to 1,000 mg/day — support setting NR's UL at least as high as niacinamide's, which is currently set at 900 mg/day. For comparison, niacin's UL is set much lower, at just 10 mg/day, because of the flushing it causes at that level (PMID 31278280). That's a proposal made by researchers studying NR, not an adopted regulatory limit — treat it as informed reasoning, not an official ceiling.
What's sold vs. what's tested
Commercial nicotinamide riboside products are sold across a wide range, commonly from around 100 mg to 900 mg or more per serving, based on the amounts people search for and the products on shelves. That range overlaps meaningfully with what's actually been tested in trials — unlike some other supplement ingredients, where commercial doses run far outside anything studied. Even so, a bigger number on a label isn't backed by more evidence: the 2,000 mg/day trial, the highest dose tested, didn't outperform lower doses on any outcome it measured (PMID 29992272).
Questions people ask
How much nicotinamide riboside per day?
There's no single research-backed answer. Trials have used daily doses from 100 mg to 2,000 mg; most chronic trials settled on 1,000 mg a day. Following the directions on whatever product you're using, and checking with a pharmacist if you're unsure, is more reliable than picking a number from this research.
How much nicotinamide riboside should I take?
The most commonly studied sustained dose across the trials reviewed here is 1,000 mg a day. That's the amount with the most research behind it for safety, not a dose shown to produce a specific benefit — see nicotinamide riboside (NR) benefits: what the research does and doesn't show for what those trials did and didn't find.
How much nicotinamide riboside is too much?
No official upper limit has been set. The highest dose tested in a controlled trial was 2,000 mg a day for 12 weeks, found safe in that trial (PMID 29992272). That's not the same as a proven ceiling — going meaningfully above what's been tested isn't backed by safety data either way.
Related reading: what is nicotinamide riboside (NR)? A plain guide, when is the best time to take nicotinamide riboside (NR)?, and nicotinamide riboside (NR) side effects.
Sources
- Nicotinamide riboside is uniquely and orally bioavailable in mice and humans The first published human trial of nicotinamide riboside (2016) found single oral doses of 100–1,000 mg produced a dose-dependent rise in blood NAD+ in 12 healthy adults, and that NR behaves differently in the body than the other two forms of vitamin B3.
- Safety and Metabolism of Long-term Administration of NIAGEN (Nicotinamide Riboside Chloride) in a Randomized, Double-Blind, Placebo-controlled Clinical Trial of Healthy Overweight Adults A 2019 randomized, placebo-controlled trial of 140 adults found nicotinamide riboside raised blood NAD+ dose-dependently at 100-1,000 mg/day over 8 weeks with no reports of flushing and no rise in LDL cholesterol or homocysteine, unlike the other forms of vitamin B3.
- Chronic nicotinamide riboside supplementation is well-tolerated and elevates NAD(+) in healthy middle-aged and older adults A 2018 crossover trial's discussion explains that niacin's flushing reaction comes from binding a specific skin receptor (GPR109A) that nicotinamide riboside isn't expected to activate, and found flushing reports were, if anything, more common on placebo than on NR.
- A randomized placebo-controlled clinical trial of nicotinamide riboside in obese men: safety, insulin-sensitivity, and lipid-mobilizing effects A 2018 trial of 40 obese men given 2,000 mg/day of NR for 12 weeks found no improvement in insulin sensitivity, glucose metabolism, or body composition compared with placebo, though it was safe and well tolerated.
- Repeat dose NRPT (nicotinamide riboside and pterostilbene) increases NAD(+) levels in humans safely and sustainably: a randomized, double-blind, placebo-controlled study A 2017 trial of a nicotinamide-riboside-and-pterostilbene combination product in 120 older adults found dose-dependent NAD+ increases (about 40% and 90% at two doses) over 8 weeks with no serious adverse events — a combination-product result, not one isolating NR alone, and no clinical outcome beyond NAD+ was measured.
*These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease.