NR (Nicotinamide Riboside)
NR (Nicotinamide Riboside) scored 6.8 / 10 (👍 Worth trying) on the BioHarmony scale as a Substance → Vitamin / Mineral / Nutrient.
What It Is
Nicotinamide riboside (NR) is a form of vitamin B3 that serves as a precursor to NAD+ via the NRK (nicotinamide riboside kinase) pathway. It is two enzymatic steps from NAD+ (NR → NMN → NAD+), compared to NMN's single step. ChromaDex's Niagen is the patented, clinically studied form with FDA GRAS status and accepted NDI notification, giving it the strongest regulatory standing of any NAD+ precursor. Type: NAD+ Precursor (Vitamin B3 Form) Current status: FDA GRAS (GRN 635), NDI accepted. Legally sold as dietary supplement worldwide. Available primarily as Tru Niagen (ChromaDex). 40+ registered human trials makes NR the most clinically studied oral NAD+ precursor.
Dosing & Protocols
Dosing information is summarized from published research and community reports. This is not a prescribing guide. Consult a healthcare provider before starting any protocol.
View 1 route and 3 protocols
Routes & Forms
| Route | Form | Clinical Range | Community Range |
|---|---|---|---|
| oral | capsule (Tru Niagen / Niagen) | 300-2000mg/day (Niagen capsules) 40+ registered human trials; most clinically studied oral NAD+ precursor | 300-600mg/day 300mg standard Tru Niagen dose; 600mg for those seeking more; most healthy adults report no subjective effect |
Protocols
Standard Tru Niagen Clinical (manufacturer recommended)
- Dose
- 300mg/day
- Frequency
- daily, morning
- Duration
- ongoing
Minimum dose with blood NAD+ elevation. Cost-effective entry point.
Clinical high-dose Clinical (Martens 2018)
- Dose
- 1000mg/day
- Frequency
- daily
- Duration
- 6-12 weeks
60% NAD+ increase; trend toward reduced BP/arterial stiffness (underpowered n=24).
Multi-precursor stack Anecdotal
- Dose
- 300mg NR + 250-500mg NMN + TMG 500mg
- Frequency
- daily, morning
- Duration
- ongoing
Nick's preferred approach - multiple NAD precursors for complementary pathway coverage.
Use-Case Specific Dosing
| Use Case | Dose | Notes |
|---|---|---|
| Longevity | 300-1000mg/day | NAD+ repletion via NRK pathway; strongest regulatory confidence (GRAS + NDI) |
| Cardiovascular | 1000mg/day | Martens 2018 trend toward reduced BP/arterial stiffness; NICE PAD improved 6MWT |
| Neuroprotection | 1000mg/day | NADPARK trial promising signals in Parkinson's; brain NAD+ elevation confirmed (Nanga 2024) |
| Metabolic Health | 1000-2000mg/day | Dollerup 2018 found NO insulin sensitivity improvement at 2g/day in obese men |
How this score is calculated →
Upside (1.55 / 5.00)
| Dimension | Weight | Score | Visual | Weighted |
|---|---|---|---|---|
| Efficacy | 25% | 2.5 | 0.625 | |
| Breadth of Benefits | 15% | 2.8 | 0.420 | |
| Evidence Quality | 25% | 3.0 | 0.750 | |
| Speed of Onset | 10% | 3.0 | 0.300 | |
| Durability | 10% | 1.5 | 0.150 | |
| Bioindividuality Upside | 15% | 2.0 | 0.300 | |
| Total | 2.545 |
Upside Rationale
Efficacy (2.5/5.0) Reliably elevates blood and tissue NAD+ (40-142%). But functional clinical outcomes are consistently null or underpowered in healthy adults. Dollerup 2018 found no insulin sensitivity improvement. Elhassan 2019 found no functional mitochondrial benefit despite elevated muscle NAD+. Disease populations (Parkinson's, PAD) show more promise. The "biochemistry works, function doesn't follow" gap is NR's central problem.
Breadth of Benefits (2.8/5.0) Same NAD+ pathways as NMN: sirtuins, PARPs, metabolic, cardiovascular, neurological. Brain NAD+ elevation confirmed (Nanga 2024). Breadth of POTENTIAL is wide, but proven human benefits are narrow.
Evidence Quality (3.0/5.0) 40+ registered trials makes NR the most studied oral NAD+ precursor. Includes Martens, Dollerup, Elhassan from independent academic labs (not just ChromaDex). NR-SAFE tested 3000mg/day safely. But ChromaDex funds most research (-0.5 penalty). Offset by better trial count and some independent work.
Speed of Onset (3.0/5.0) Blood NAD+ within hours. Brain NAD+ within 4 hours (Nanga 2024). Functional outcomes, when they exist, require weeks to months.
Durability (1.5/5.0) NAD+ returns to baseline on cessation. Maintenance required.
Bioindividuality Upside (2.0/5.0) Healthy adults consistently report no subjective effect. Disease populations respond better. Age-related NAD+ decline means older adults have larger deficit to fill, but even there, functional outcomes are elusive.
Downside (0.37 / 5.00)
| Dimension | Weight | Score | Visual | Weighted |
|---|---|---|---|---|
| Safety Risk | 30% | 1.3 | 0.390 | |
| Side Effect Profile | 15% | 1.3 | 0.195 | |
| Financial Cost | 5% | 3.0 | 0.150 | |
| Time/Effort Burden | 5% | 1.2 | 0.060 | |
| Opportunity Cost | 5% | 2.5 | 0.125 | |
| Dependency / Withdrawal | 15% | 1.0 | 0.150 | |
| Reversibility | 25% | 1.0 | 0.250 | |
| Total | 1.320 | |||
| Harm subtotal × 1.4 | 1.379 | |||
| Opportunity subtotal × 1.0 | 0.335 | |||
| Combined downside | 1.714 | |||
| Baseline offset (constant) | −1.340 | |||
| Effective downside penalty | 0.374 |
Downside Rationale
Safety Risk (1.3/5.0) GRAS status. Well-tolerated up to 3000mg/day (NR-SAFE 2023). No methyl depletion at high doses. No SAEs across all trials. Same theoretical cancer concern as NMN but equally undemonstrated.
Side Effect Profile (1.3/5.0) Mild GI, occasional headache. Flushing rare (unlike niacin). Very benign.
Financial Cost (3.0/5.0) Tru Niagen $40-50/mo at 300mg. $70-100 at 600mg. ChromaDex patent means limited generic competition.
Time/Effort Burden (1.2/5.0) Capsule. Minimal.
Opportunity Cost (2.5/5.0) Same as NMN: lifestyle NAD boosters are free alternatives.
Dependency/Withdrawal (1.0/5.0) No dependency.
Reversibility (1.0/5.0) Fully reversible.
Verdict
✅ Best for: Adults seeking NAD+ repletion with the strongest regulatory confidence (GRAS + NDI). Especially suitable for those who prioritize product quality assurance (Tru Niagen) over cost. Disease populations (Parkinson's, peripheral artery disease) have the most promising functional data. Best as part of a multi-precursor strategy.
❌ Avoid if: Price-sensitive (expensive for something most healthy adults don't feel). Expecting dramatic subjective effects (most users report nothing). The evidence gap between "NAD+ goes up" and "you feel/function better" remains NR's Achilles' heel.
Use Case Breakdown
The overall BioHarmony score reflects the intervention's primary evidence profile. These subratings are independent assessments per use case.
| Use Case | Score | Summary |
|---|---|---|
| ⚖️ Mitochondrial | 5.5 | Elhassan 2019 elevated muscle NAD+ but no functional mitochondrial improvement; biochemistry without function |
| ⚖️ Cardiovascular | 5.0 | Martens 2018 trend toward reduced BP/arterial stiffness; NICE PAD improved 6-minute walk in PAD |
| ⚖️ Metabolic Health | 5.0 | NAD+ elevation supports metabolic pathways; Dollerup 2018 null for insulin sensitivity in obese |
| ⚖️ Neuroprotection | 5.0 | NADPARK 2022 promising Parkinson's signals; Nanga 2024 confirmed brain NAD+ elevation (~17%) within 4 hours |
| ⚖️ Longevity / Lifespan | 5.0 | NAD+ decline is established aging hallmark; NRK pathway well-characterized; no human lifespan data |
| ⚖️ Healthspan | 5.0 | Multi-system NAD+ support; disease populations show more promise than healthy adults |
| ⚖️ Geriatric / Aging Population | 5.0 | Older adults have largest NAD+ deficit; disease populations (PD, PAD) show more functional promise |
| ○ Energy / Fatigue | 4.5 | NAD+ essential for cellular energy; most healthy adults report no subjective effect despite biochemical elevation |
| ○ Nerve Regeneration | 3.5 | NAD+ supports neuronal health; NADPARK data suggests neuroprotective potential |
| ○ Endurance / Cardio | 3.5 | Dolopikou 2020 exercise performance data; NICE PAD improved walking distance |
| ○ Anti-Inflammatory | 3.5 | Elhassan 2019 cytokine data; indirect anti-inflammatory pathway |
| ○ Blood Sugar / Glycemic Control | 3.0 | Dollerup 2018 explicitly null for insulin sensitivity in obese men at 2g/day |
| ○ Cognition / Focus | 3.0 | Long-COVID 2025 trial: NAD+ elevated but cognition/fatigue not improved vs placebo |
| ○ Recovery / Repair | 3.0 | NAD+ supports PARP-mediated DNA repair; indirect mechanism |
| ○ Cellular Senescence | 3.0 | NAD+ supports DNA repair pathways; indirect senescence reduction |
How This Score Could Change
BioHarmony scores are living assessments. New research, regulatory changes, or personal context can shift the score up or down. These are the most likely scenarios that would change this intervention's rating.
| Scenario | Dimension changes | New score |
|---|---|---|
| NADPARK Phase 3 confirms Parkinson's benefit | Efficacy 2.5→3.5, Evidence 3.0→3.8 | 7.6 / 10 💪 Strong recommend |
| Large independent RCT shows functional benefit in healthy elderly | Efficacy 2.5→3.2, Bioindividuality 2.0→3.0 | 7.3 / 10 💪 Strong recommend |
| 5-year safety data (clean) | Evidence 3.0→3.5 | 7.0 / 10 💪 Strong recommend |
| Multiple null RCTs continue stacking | Efficacy 2.5→2.0 | 6.5 / 10 👍 Worth trying |
Key Evidence Sources
- Martens CR et al. NR supplementation and vascular function. Nature Communications 2018 — 60% NAD+ increase; trend toward reduced BP/arterial stiffness (n=24, underpowered)
- Dollerup OL et al. NR and insulin sensitivity in obese men. J Physiology 2018 — NO insulin sensitivity improvement at 2g/day in obese men
- Elhassan YS et al. NR augments human skeletal muscle NAD+ metabolome. Cell Reports 2019 — Elevated muscle NAD+ but no functional mitochondrial improvement
- Remie CME et al. NR metabolic effects. Am J Clin Nutr 2020 — Metabolic effects in overweight older adults
- Brakedal B et al. NADPARK: NR in Parkinson's disease. Cell Metabolism 2022 — Promising signals in Parkinson's disease; brain NAD+ and clinical measures
- Lapatto HAK et al. NR-SAFE: Safety at 3000mg/day. 2023 — Safe at 3000mg/day; no methyl depletion
- Nanga RPR et al. Brain NAD+ elevation by 7T MRS after NR. 2024 — First evidence NR elevates brain NAD+ (~17%) within 4 hours
- Conze DB et al. Safety of NR up to 2000mg. 2019 — Safety and pharmacokinetics at high doses
- Dolopikou CF et al. NR and exercise performance. Exp Gerontol 2020 — Exercise performance outcomes
- Dollerup OL et al. Follow-up metabolic analysis. 2020 — Extended metabolic analysis from original obese cohort
- Airhart SE et al. NR pharmacokinetics. PLoS One 2017 — First-in-human pharmacokinetics study
- Brenner C. NR review. Annual Review of Nutrition 2019 — Comprehensive review of NR biology and clinical evidence
Other interventions for Cardiovascular
See all ratings →📊 How BioHarmony scoring works
BioHarmony translates a weighted expected-value calculation into a reader-facing 0–10 score. 5.0 is neutral (benefits and risks balance). Above 5 = benefits outweigh risks; below 5 = risks outweigh benefits.
Harm-type downsides (safety risk, side effects, reversibility, dependency) carry a 1.4× precautionary multiplier. Harm weighs more than benefit. Opportunity-type downsides (financial cost, time/effort, opportunity cost) are subtracted at face value.
Use case subratings are independent assessments of how well the intervention addresses specific health goals. They are not components of the overall score. Each subrating reflects the scorer's judgment based on use-case-specific evidence, safety, and effect sizes.
Every dimension is evaluated on a 1–5 scale, and the baseline (1) is subtracted before weighting. A perfect intervention with zero downsides contributes zero penalty rather than a residual floor, so top-tier scores are actually reachable.
EV = Upside − Downside
EV = 1.545 − 0.374 = 1.171
EV ranges from −5 to +5. Adding 7 shifts to 2–12, dividing by 12 normalizes to 0–1, then ×10 gives the 0–10 score.
Score = ((1.171 + 7) / 12) × 10 = 6.8 / 10
