NMN (Nicotinamide Mononucleotide)
NMN (Nicotinamide Mononucleotide) scored 6.8 / 10 (👍 Worth trying) on the BioHarmony scale as a Substance → Vitamin / Mineral / Nutrient.
What It Is
Nicotinamide mononucleotide (NMN) is the direct precursor to NAD+ (nicotinamide adenine dinucleotide) in the mammalian salvage pathway. NAD+ is essential for sirtuin activation, PARP-mediated DNA repair, and over 500 enzymatic reactions. Tissue NAD+ levels decline approximately 50% between ages 40-60, driving interest in precursor supplementation. NMN bypasses the rate-limiting NAMPT enzyme, directly feeding the final conversion step to NAD+. Type: NAD+ Precursor (Vitamin B3 Derivative) Current status: FDA NDI dispute (technically not legal as a US supplement since 2022, but widely sold). Legal in Japan, EU, and most other markets. David Sinclair conflict of interest: co-founded Metro Biotech, holds patents, prominent advocate.
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 2 routes and 3 protocols
Routes & Forms
| Route | Form | Clinical Range | Community Range |
|---|---|---|---|
| oral | capsule / powder | 250-1000mg/day 10+ RCTs at 250-1000mg/day; Yoshino 2021 used 250mg | 250-1000mg/day (500mg most common) Community consensus on 500mg/day morning dosing; 20-30% feel nothing |
| sublingual | sublingual tablet | No RCT comparing sublingual vs oral; theoretical advantage unvalidated | 250-500mg sublingual tablets Theoretical faster absorption; no clinical comparison data |
Protocols
Standard oral Clinical + anecdotal
- Dose
- 500mg/day
- Frequency
- daily, morning
- Duration
- ongoing
Most common community dose. Blood NAD+ elevation within hours, steady-state at ~2 weeks.
Clinical dose Clinical (Yoshino 2021)
- Dose
- 250mg/day
- Frequency
- daily
- Duration
- minimum 10 weeks
Lowest clinically validated dose; +25% muscle insulin sensitivity in prediabetic women.
Multi-precursor stack Anecdotal
- Dose
- 250-500mg NMN + 300mg NR + TMG 500mg
- Frequency
- daily, morning
- Duration
- ongoing
Nick's preferred approach - multiple NAD precursors plus TMG for methyl donor preservation.
Use-Case Specific Dosing
| Use Case | Dose | Notes |
|---|---|---|
| Metabolic Health | 250-500mg/day | +25% muscle insulin sensitivity (Yoshino 2021); modest glucose/insulin improvements per meta-analysis |
| Energy | 500mg/day | NAD+ elevation supports mitochondrial function; subjective energy improvement in ~70% of respondents |
| Longevity | 500-1000mg/day | Sirtuin activation, PARP-mediated DNA repair via NAD+ elevation; no hard clinical endpoints yet |
| Mitochondrial | 500mg/day | NAD+ is essential cofactor for mitochondrial electron transport chain |
How this score is calculated →
Upside (1.68 / 5.00)
| Dimension | Weight | Score | Visual | Weighted |
|---|---|---|---|---|
| Efficacy | 25% | 2.8 | 0.700 | |
| Breadth of Benefits | 15% | 3.0 | 0.450 | |
| Evidence Quality | 25% | 2.8 | 0.700 | |
| Speed of Onset | 10% | 3.0 | 0.300 | |
| Durability | 10% | 1.5 | 0.150 | |
| Bioindividuality Upside | 15% | 2.5 | 0.375 | |
| Total | 2.675 |
Upside Rationale
Efficacy (2.8/5.0) Reliable NAD+ elevation of 38-100% across studies. One well-designed clamp study shows +25% muscle insulin sensitivity (Yoshino 2021). Gait speed improvement in elderly (Igarashi 2022). But no hard clinical endpoints (mortality, CV events, cancer). Most outcomes are surrogate markers.
Breadth of Benefits (3.0/5.0) NAD+ affects sirtuins, PARPs, CD38 across metabolic, cardiovascular, neurological, and cellular repair systems. Human evidence currently limited to metabolic and physical function endpoints.
Evidence Quality (2.8/5.0) 10+ published RCTs and growing rapidly. But small samples (20-50 per arm), short durations (10-12 weeks max), surrogate endpoints only. Sinclair/Metro Biotech conflicts of interest. Some independent replication emerging. Industry funding penalty offset by growing trial count.
Speed of Onset (3.0/5.0) Blood NAD+ elevation within hours. Steady-state at ~2 weeks. Functional outcomes require 8-12 weeks.
Durability (1.5/5.0) NAD+ returns to baseline within days to weeks of cessation. Maintenance supplementation required.
Bioindividuality Upside (2.5/5.0) Older and metabolically unhealthy individuals benefit most (greater NAD+ deficit). Yoshino 2021 found stronger effects in higher BMI/insulin resistance. 20-30% of community report feeling nothing.
Downside (0.50 / 5.00)
| Dimension | Weight | Score | Visual | Weighted |
|---|---|---|---|---|
| Safety Risk | 30% | 1.5 | 0.450 | |
| Side Effect Profile | 15% | 1.5 | 0.225 | |
| 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 | 1.410 | |||
| Harm subtotal × 1.4 | 1.505 | |||
| Opportunity subtotal × 1.0 | 0.335 | |||
| Combined downside | 1.840 | |||
| Baseline offset (constant) | −1.340 | |||
| Effective downside penalty | 0.500 |
Downside Rationale
Safety Risk (1.5/5.0) Well-tolerated up to 1250mg/day in trials. No SAEs. Theoretical cancer concern (NAD+ fueling cancer cells) is mechanistically plausible but undemonstrated in humans. Avoid during active cancer or PARP inhibitor therapy.
Side Effect Profile (1.5/5.0) Minor GI, insomnia if taken late. Generally very mild.
Financial Cost (3.0/5.0) $30-80/mo. Expensive for something 20-30% of users don't feel.
Time/Effort Burden (1.2/5.0) Capsule or powder. Minimal.
Opportunity Cost (2.5/5.0) Lifestyle NAD boosters (exercise, fasting, sauna, cold exposure) are free and proven. NMN supplements on top of these may offer diminishing returns.
Dependency/Withdrawal (1.0/5.0) No withdrawal. NAD+ returns to baseline.
Reversibility (1.0/5.0) Fully reversible.
Verdict
✅ Best for: Adults over 40 with declining NAD+ levels, particularly those with metabolic dysfunction, insulin resistance, or age-related physical decline. Best used as part of a multi-precursor NAD strategy (NMN + NR + niacin) alongside lifestyle fundamentals (exercise, fasting, sauna). Co-supplement with TMG for methyl donor preservation.
❌ Avoid if: Active cancer (theoretical NAD+ fueling concern). On PARP inhibitors. Price-sensitive (may not justify cost without subjective benefit). Already optimizing NAD+ through lifestyle practices alone.
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 |
|---|---|---|
| 👍 Metabolic Health | 6.5 | +25% muscle insulin sensitivity (Yoshino 2021 clamp study); meta-analysis confirms modest glucose improvements |
| 👍 Mitochondrial | 6.0 | NAD+ is essential cofactor for mitochondrial electron transport; 38-100% elevation demonstrated |
| ⚖️ Longevity / Lifespan | 5.5 | Mills 2016 mouse lifespan data; NAD+ decline is established aging hallmark; no human lifespan data |
| ⚖️ Healthspan | 5.5 | Multi-system NAD+ decline with age; sirtuin activation pathway; human functional data emerging |
| ⚖️ Energy / Fatigue | 5.5 | NAD+ is essential for cellular energy metabolism; ~70% of users report subjective improvement |
| ⚖️ Geriatric / Aging Population | 5.5 | Older adults have largest NAD+ deficit (~50% decline by age 60); Igarashi 2022 gait speed improvement in elderly |
| ⚖️ Blood Sugar / Glycemic Control | 5.0 | Yoshino 2021 insulin sensitivity improvement; Zhong 2024 meta-analysis confirms modest glycemic benefit |
| ○ Cardiovascular | 4.0 | Preclinical vascular dysfunction reversal (de Picciotto 2016); no human cardiovascular RCTs |
| ○ Endurance / Cardio | 4.0 | Liao 2021: aerobic capacity improvement in runners |
| ○ Skin / Beauty | 3.5 | Nouri 2023 skin aging trial; limited data |
| ○ Neuroprotection | 3.5 | NAD+ supports neuronal health via sirtuin/PARP pathways; preclinical only |
| ○ Strength / Power | 3.5 | Indirect via mitochondrial support; no direct strength RCT |
| ○ Recovery / Repair | 3.5 | NAD+ supports PARP-mediated DNA repair; indirect mechanism |
| ○ Anti-Inflammatory | 3.5 | NAD+ supports anti-inflammatory pathways; indirect mechanism |
| ○ Cellular Senescence | 3.5 | NAD+ supports DNA repair via PARPs, potentially reducing senescent cell accumulation; indirect |
| ○ Cognition / Focus | 3.0 | Preclinical neuroprotection only; no completed human cognitive data |
| ○ Sleep Quality | 3.0 | Anecdotal reports of improved sleep; insomnia if taken late; no RCT data |
| ○ Body Composition / Fat Loss | 3.0 | Indirect metabolic effects; no direct body composition RCT |
| ○ Muscle Growth / Hypertrophy | 3.0 | Indirect via mitochondrial and metabolic support; no direct evidence |
| ○ Antioxidant / Oxidative Stress | 3.0 | NAD+ supports cellular redox balance; not a direct antioxidant |
| ○ Telomere / DNA Repair | 3.0 | PARP-mediated DNA repair; indirect telomere maintenance; no direct evidence |
| ○ Autophagy | 3.0 | NAD+-sirtuin axis involved in autophagy signaling; indirect |
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 |
|---|---|---|
| Large independent RCT confirms insulin sensitivity + aging biomarkers | Evidence 2.8→3.8, Efficacy 2.8→3.5 | 7.7 / 10 💪 Strong recommend |
| 5-year safety study with cancer incidence data (clear) | Safety 1.5→1.2, Evidence 2.8→3.5 | 7.4 / 10 💪 Strong recommend |
| FDA resolves NDI dispute, NMN legal as supplement | (Legal only, doesn't change score) | 6.8 / 10 (unchanged) |
| Cancer case series in long-term users emerges | Safety 1.5→3.0 | 5.9 / 10 👍 Worth trying |
Key Evidence Sources
- Yoshino J et al. NMN improves muscle insulin sensitivity. Science 2021 — +25% muscle insulin sensitivity (clamp-measured) in prediabetic women at 250mg/day
- Yi L et al. Multi-dose NMN efficacy and safety. 2023 — Dose-dependent NAD+ elevation; walking endurance improvement at 600mg+
- Igarashi M et al. NMN and gait speed in older men. 2022 — Gait speed improvement in elderly men
- Liao B et al. NMN and aerobic capacity in runners. 2021 — Aerobic capacity improvement in amateur runners
- Pencina KM et al. MIB-626 NAD+ elevation. 2023 — 1000mg MIB-626, ~2x NAD+ at 14 days
- Katayoshi T et al. NAD+ elevation in middle-aged adults. 2023 — NAD+ elevation confirmed in middle-aged adults
- Zhong O et al. Meta-analysis of NMN RCTs. 2024 — Confirmed NAD+ elevation; modest glucose/insulin improvements across trials
- Grozio A et al. Slc12a8 NMN transporter. 2019 — Discovery of direct NMN transporter in mammalian cells
- Mills KF et al. Long-term NMN in mice. Cell Metabolism 2016 — Anti-aging effects of long-term NMN administration in mice
- de Picciotto NE et al. NMN reverses vascular dysfunction. Aging Cell 2016 — Vascular dysfunction reversal in aged mice
- Massudi H et al. Age-related NAD+ decline. PLoS One 2012 — Characterized ~50% NAD+ decline between ages 40-60
- Nouri M et al. NMN and skin aging. 2023 — NMN effects on skin aging parameters
Other interventions for Energy / Fatigue
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 = 1.675 − 0.500 = 1.175
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 = ((1.175 + 7) / 12) × 10 = 6.8 / 10
