NAD+ Precursor
NMNNicotinamide Mononucleotide
The direct precursor with dedicated intestinal transport.
Nicotinamide mononucleotide (NMN) is a nucleotide derivative of nicotinamide that sits one enzymatic step upstream of NAD+. Human trials published between 2019 and 2023 demonstrate reliable elevation of whole-blood NAD+ concentrations at doses between 250 mg and 900 mg daily, with a favorable short-term safety profile.
What are the pharmacokinetics of NMN?
- Half-life
- ~35 minutes (plasma)
- Time to peak (Tmax)
- 15 min (sublingual), 30-60 min (oral)
- Clearance
- Rapid hepatic uptake and conversion to NAD+
NMN is converted to nicotinamide riboside in the gut lumen, then reassembled intracellularly — the Slc12a8 direct transport pathway supplements this route.
What doses of NMN have been studied?
Typical use
250-500 mg/day
Clinically studied
100 mg – 900 mg/day in published human trials
Safety ceiling
900 mg/day sustained over 60 days (Yamaguchi et al. 2022)
How can NMN be delivered?
Which mechanisms does NMN affect?
What does the research on NMN show?
Nature Metabolism · 2019 · PMID 30725698
Slc12a8 is a nicotinamide mononucleotide transporter
Grozio A, et al.
Identified Slc12a8 as a dedicated NMN transporter in the small intestine — established the pharmacological basis for oral NMN bioavailability.
Read summaryScience · 2021 · PMID 33888596
Safety and metabolism of long-term administration of NMN in healthy adults
Yoshino M, et al.
10-week, 250 mg/day NMN supplementation in postmenopausal women improved muscle insulin sensitivity — one of the first mechanistic human trials.
Read summary
Frequently asked questions
- Is NR or NMN better for raising NAD+?
- Both reliably raise blood NAD+ at studied doses. NMN has a dedicated intestinal transporter (Slc12a8) and higher sublingual bioavailability, while NR has the longer human safety record and the most published placebo-controlled trials. Neither has been shown superior in head-to-head human data.
- What is the optimal NMN or NR dosage?
- Published human trials use 250-1,000 mg/day for both NMN and NR. The dose-response for NAD+ elevation plateaus around 500-600 mg/day in most studies — higher doses raise blood NAD+ further but with diminishing tissue-level returns. There is no established clinical dose for longevity outcomes.
- Is long-term NAD+ supplementation safe?
- Short-term (up to 12 weeks) NMN and NR supplementation at studied doses shows a favorable safety profile with no serious adverse events in published trials. Long-term (multi-year) human safety data does not yet exist. Known considerations include methyl donor depletion, potential sirtuin inhibition at very high nicotinamide doses, and unclear interactions with some chemotherapies.
- Should NMN be taken sublingually or orally?
- Sublingual NMN bypasses gut degradation and first-pass liver metabolism, producing faster and higher peak plasma concentrations than oral capsules in the available human pharmacokinetic data. For most users, sublingual routes deliver more NMN to tissues per milligram dosed — though oral remains cheaper and more convenient.
- Is IV NAD+ worth it?
- IV NAD+ rapidly raises plasma NAD+ to supraphysiological levels, but the available research shows most of this is cleared or degraded before reaching intracellular compartments. Clinics report subjective benefits for fatigue and recovery; controlled efficacy trials are sparse. Cost ($300-800 per session) is significantly higher than oral precursor protocols.