An open-label, non-randomized study of the pharmacokinetics of the nutritional supplement nicotinamide riboside (NR) and its effects on blood NAD+ levels in healthy volunteers.
Level 4 - case-series / case-control
Open-label, non-randomized single-arm pharmacokinetic study without a control group
PubMed 29211728 · doi:10.1371/journal.pone.0186459
What was done
Eight healthy volunteers enrolled in an open-label, non-randomized pharmacokinetic study. Oral nicotinamide riboside (NR) was administered at 250 mg daily on Days 1 and 2, then uptitrated to a peak dose of 1000 mg twice daily on Days 7 and 8. On Day 9, subjects completed a 24-hour pharmacokinetic assessment following a single 1000 mg NR dose. Whole-blood NR levels, clinical chemistry, and whole-blood NAD+ concentrations were analyzed.
What was found
Oral NR was well tolerated with no reported adverse events. Significant increases from baseline to steady-state mean concentrations were observed for both NR (p = 0.03) and NAD+ (p = 0.001), with NAD+ concentrations increasing by 100%. Absolute changes in NR and NAD+ from baseline to Day 9 correlated significantly (R2 = 0.72, p = 0.008).
Why it matters
This study provides human pharmacokinetic data demonstrating that oral NR is bioavailable and substantially raises circulating NAD+ levels, establishing dosing parameters for future clinical trials.
Limits
The study is limited by a very small sample size (n = 8), an open-label design with no control group, and a short duration (9 days). Clinical outcomes and long-term safety were not evaluated.
Cited by
- supports Nicotinamide riboside increases blood NAD levels within 6 to 8 hours after ingestion.