Nicotinamide Riboside (NR) Supplementation Dosing
For generally healthy adults, the recommended dose of nicotinamide riboside is 250-1000 mg per day, taken once or twice daily with or without food, based on FDA-approved labeling and clinical trial data. 1
Standard Dosing Regimens
The FDA-approved dosing for NR is one or two tablets (typically 250-500 mg per tablet) taken once or twice daily, which translates to a daily range of 250-2000 mg. 1 However, clinical evidence supports more specific recommendations:
Evidence-Based Dose Ranges
Low dose (100-300 mg/day): Increases whole blood NAD+ by 22-51% within 2 weeks and is well-tolerated with no significant adverse events 2
Moderate dose (500-1000 mg/day): Most commonly studied in clinical trials for cardiovascular benefits, taken as 500 mg twice daily (total 1000 mg/day) 3, 4
High dose (1000 mg/day): Increases NAD+ levels by 142% and remains safe without flushing or adverse metabolic effects 2
Practical Administration
NR can be taken with or without food, and the dose can be split into once or twice daily administration based on convenience. 1 The twice-daily regimen (e.g., 500 mg morning and evening) has been most extensively studied in clinical trials 3, 4, though once-daily dosing is also FDA-approved 1.
Safety Profile and Upper Limits
NR supplementation up to 1000 mg/day for 8 weeks has demonstrated excellent safety with no flushing, no elevation of LDL cholesterol, and no dysregulation of 1-carbon metabolism. 2 This distinguishes NR from nicotinic acid, which causes flushing at doses as low as 30 mg 5, 6.
- Animal toxicity studies established a no-observed-adverse-effect-level (NOAEL) of 300-500 mg/kg/day in rats 7, 8
- Human trials up to 2000 mg/day (1000 mg twice daily) for 6-8 weeks showed no significant adverse events compared to placebo 2, 4
- The European Food Safety Authority's upper limit for nicotinamide (a related compound) is approximately 900 mg/day for adults, though NR has shown safety at higher doses 5
Duration of Treatment
Clinical trials have demonstrated sustained NAD+ elevation with continuous supplementation for 6-12 weeks, with benefits maintained throughout the treatment period. 3, 2, 4 The increases in NAD+ metabolites occur within 2 weeks and are sustained with ongoing supplementation 2.
Important Clinical Considerations
Unlike nicotinic acid (niacin), NR does not cause flushing and has a more favorable safety profile at therapeutic doses. 5, 6 This is a critical distinction when counseling patients who may have experienced flushing with other forms of vitamin B3.
- No hepatotoxicity has been observed at doses up to 1000 mg/day in humans, unlike high-dose nicotinic acid (3 g/day) which can cause liver injury 5, 2
- No monitoring of liver function tests is required for standard NR supplementation 2, 4
- NR does not require the extensive monitoring needed for high-dose nicotinic acid therapy 5
Population-Specific Guidance
For middle-aged and older adults (≥50 years) with cardiovascular risk factors, the evidence supports 500 mg twice daily (1000 mg/day total) as the optimal dose for reducing blood pressure and arterial stiffness. 3, 4 This population experiences age-related NAD+ decline and may benefit most from supplementation 5.