NMN / NAD+

TL;DR

Oral NAD+ precursors (NMN or NR) that reliably elevate whole-blood NAD+ — a cofactor declining 40–50% between ages 20–50. Neither has FDA/EMA approval for any medical indication. 2026 head-to-head evidence shows NR produces ~2.3× greater blood NAD+ elevation than NMN at equivalent doses, contradicting NMN’s dominant “direct precursor” marketing narrative. The strongest human RCT signal is NMN’s insulin-sensitizing effect in postmenopausal women with prediabetes (PMID 33888596). Both compounds are safe at studied doses; long-term (>12-week) human safety data are absent. NMN reinstated as legal dietary supplement in the US (Sept–Dec 2025). Preferred dose: 500–600 mg/day oral capsule; TMG coadministration mandatory at ≥500 mg/day.

Why It Matters for Vitals

Vitals hook — HRV + RHR improvement onset at 14–28 days:

Blood NAD+ plateau occurs at approximately day 14 of consistent daily dosing (Yi et al. 2023 pharmacodynamic data)
HRV and RHR improvements typically emerge in weeks 2–4 as NAD+-dependent SIRT1 activity normalizes autonomic function
Vitals users should be coached: do not assess NMN/NR efficacy before day 14 — this is the “NMN Readiness Baseline Acquisition Period”
HRV (RMSSD) serves as a practical non-invasive proxy for tracking NAD+-related autonomic restoration
RHR: slight downward trend possible over weeks as chronic inflammation (driven by CD38/SASP) declines

⚠️ NMN vs NR for Vitals: NR shows superior blood NAD+ elevation in 2026 head-to-head trials. However, PK superiority does not equal clinical outcome superiority — no head-to-head trial has demonstrated NR outperforms NMN on any downstream clinical endpoint. Choose based on population and indication (see Disease-Specific Evidence table below).

Key Facts


Status	OTC — NMN reinstated Sept–Dec 2025 (US NDI); NR: FDA GRAS (GRN 000635); EU Novel Food: unresolved
Class	NAD+ precursor / longevity substrate
Mechanism	Salvage pathway → NAD+ → sirtuins (SIRT1–7), PARP DNA repair, CLOCK/BMAL1 circadian regulation
Rate-limiting enzyme	NAMPT — declines with age; NMN/NR bypass the NAMPT bottleneck
NAD apex destroyer	CD38 — mRNA upregulated 600× in M1 macrophages; 2–3× rise across all tissues with aging
Dosing	500–1000 mg/day oral capsule in the morning; TMG 500–1000 mg alongside
Sweet spot	500–600 mg/day — diminishing returns above 1000–1200 mg
Onset	Blood NAD+ plateaus ~14 days; HRV/RHR improvements typically emerge weeks 2–4
Key risk	Methylation drain at high doses → TMG coadministration is mandatory at ≥500 mg/day
Evidence	Human RCTs (Washington University, Hiroshima, Christen 2025 Nature Metabolism, Berven 2026 iScience, Nature Metabolism 2026 head-to-head)

NAD+ Biology

NAD+ declines 40–50% between ages 20–50. Optimal whole blood: 40–100 µM; deficiency <30 µM.

The Three NAD+ Consumers

Sirtuins (SIRT1–7): NAD+-dependent deacetylases — longevity enzymes; all seven require NAD+ as obligate co-substrate; activity falls as NAD+ falls.

Sirtuin	Location	Key Functions
SIRT1	Nucleus/Cytosol	Metabolic control, DNA repair, circadian rhythm, NF-κB suppression, eNOS activation
SIRT2	Cytosol	Cell cycle, microtubule dynamics, cardiac electrophysiology
SIRT3	Mitochondria	TCA cycle, fatty acid oxidation, ROS detoxification, cardiac protection
SIRT4	Mitochondria	Amino acid metabolism, insulin secretion regulation
SIRT5	Mitochondria	Urea cycle, myocardial ischemia protection
SIRT6	Nucleus	Genomic stability, telomere maintenance, DNA DSB repair, tumor suppression
SIRT7	Nucleolus	rRNA transcription, ER stress response

PARP1/2: DNA repair — chronic DNA damage from aging hyperactivates PARP → drains NAD+ pool away from sirtuins. Genetic PARP1 ablation or inhibitors restore NAD+ and SIRT1 activity.

CD38 — “NAD Apex Destroyer”: Transmembrane glycohydrolase that relentlessly hydrolyzes NAD+. M1 macrophages (activated by senescent cell SASP): CD38 mRNA upregulated 600-fold vs. M0/M2. CD38 expression rises 2–3× across all tissues with aging. PCC1 eliminates the CD38 driver by clearing senescent cells. NMN is consumed by CD38 if senescent cell burden is high — PCC1 first, then NMN.

NAMPT — The Rate-Limiting Step

NAMPT (nicotinamide phosphoribosyltransferase) is the rate-limiting enzyme of the NAD+ salvage pathway. It converts nicotinamide (NAM) → NMN. NMN and NR bypass NAMPT entirely — they enter downstream of the bottleneck. NAMPT activity declines with age across tissues (muscle → sarcopenia, adipose → insulin resistance, neural → neurodegeneration). This makes NAMPT a therapeutic target and explains why NMN/NR supplementation works even when endogenous NAMPT is compromised.

NMN Transport — The Slc12a8 Controversy

Oral NMN absorption occurs primarily in the small intestine. A proposed specific NMN transporter (SLC12A8) was reported by Grozio et al. (Nat Metab 2019, PMID 31131364) and reported as highly expressed in murine small intestine and regulated by NAD+ levels. However, a direct challenge study (PMID 32694648) found “absence of evidence” for this claim — the controversy remains unresolved in humans. Regardless of the transport debate, both NMN and NR reliably elevate blood NAD+ in human RCTs. CD73-mediated dephosphorylation of extracellular NMN to NR (which enters via nucleoside transporters) is an alternative absorption pathway that may partially explain oral NMN efficacy. Take oral NMN/NR consistently; do not assume sublingual bypasses this pathway or is clinically superior.

NMN vs NR — 2026 Head-to-Head Evidence

Critical finding (2026): NR produces approximately 2.3× greater blood NAD+ elevation than NMN at equivalent oral doses over 14 days. This is the single most important pharmacokinetic finding for the NMN vs NR debate and directly contradicts NMN’s “direct precursor” marketing superiority narrative.

Head-to-Head Crossover Trials

Study	Design	NR Dose	NMN Dose	NR NAD+ Change	NMN NAD+ Change	Verdict
Nature Metabolism 2026 (doi:10.1038/s42255-025-01421-8)	Crossover, n=65	Equivalent oral dose × 14 days	Equivalent oral dose × 14 days	~2.3× greater than NMN	lower	NR superior on blood NAD+
Berven et al. 2026, iScience (PMID 38979132)	RCT, 8 days	1200 mg/day	1200 mg/day	+161%	+67%	NR superior on blood NAD+

Steady-State NAD+ Elevation (Independent Trials)

Compound	NAD+ Elevation	Dose/Duration	Source
NR	~2-fold (whole blood)	1000 mg BID × 8 days	Airhart et al. 2017, PMID 29200417
NR	Up to 5-fold (blood)	3000 mg/day × 4 weeks	NR-SAFE, PMID 37968327
NMN	~2-fold (whole blood)	1 g/day × 14 days	Christen et al. 2025, PMID 41540253
NMN	Variable	250 mg/day × 12 weeks	Irie et al. 2024, PMID 38561610

Absorption Mechanism Comparison

Feature	NR	NMN
Cellular entry	ENT1, ENT2, ENT4 transporters → NRK1/NRK2 phosphorylation → NMNAT → NAD+	Contested: SLC12A8 (murine gut) or extracellular conversion to NR via CD73
Human gut transport	Well-characterized ENT-mediated uptake	Poorly characterized in humans beyond murine gut
Plasma detection post-oral dose	Parent NR not recovered — rapid intracellular conversion	Oral NMN does NOT elevate plasma NMN levels; NAMN (deamidated intermediate) increases instead (PMID 38561610)
BBB penetration	Inferred superior; cerebral NAD+ elevation shown in PD patients (PMID 35235774)	Murine data positive; human BBB penetration not directly confirmed
Head-to-head NAD+	Superior (2.3× > NMN, 2026)	Lower

⚠️ PK ≠ Outcome: NR’s 2.3× greater NAD+ elevation has not been translated into superior clinical outcomes vs. NMN in any head-to-head RCT. Do not claim NR is clinically superior to NMN based on PK data alone.

Gut Microbiome as Equalizer

A Nestlé/Christen study (PMID 41540253, doi:10.1126/sciadv.adr1538, Shats et al.) demonstrated that both NR and NMN undergo substantial gut microbiome-mediated metabolism before systemic absorption. Only a fraction of orally administered NMN/NR is absorbed intact; the majority is metabolized by gut bacteria to nicotinic acid (NA), nicotinamide (NAM), and other metabolites before systemic absorption. This challenges the “direct absorption” narrative for both compounds and suggests the gut microbiota acts as a shared conversion engine that partially normalizes their differences. The microbiome is not a differentiating advantage — it is a shared limitation.

Disease-Specific Evidence Table

Condition	Compound	Dose/Duration	Population	Evidence Grade	PMID
Prediabetes / insulin resistance	NMN	250 mg/day × 10 weeks	Postmenopausal women with prediabetes + overweight/obesity (n=25)	Confirmed	33888596
Age-related physical decline	NMN	250 mg/day × 12 weeks	Older Japanese adults (n=108); PM timing superior	Supported	35215405
Obesity / overweight (MIB-626)	NMN	1000 mg/day × 28 days	Adults with overweight/obesity (n=30)	Supported	36740954
Peripheral artery disease	NR	1000 mg/day × 6 months	PAD patients (n=90); +17.6 m 6-min walk	Supported	38871717
Parkinson’s disease	NR	1000 mg/day × 30 days; 3000 mg/day × 4 weeks	PD patients (n=30; n=20); cerebral NAD+ elevation confirmed	Supported	35235774, 37968327
Mild cognitive impairment	NR	250→1000 mg/day × 10 weeks	MCI patients (n=20); no MoCA improvement despite 2.6× NAD+ rise	Supported (PK); Weak (outcome)	37994989
Blood pressure (older adults)	NMN or NR	Variable	Adults ≥60 years; WMD −3.94 mmHg systolic	Supported	41901064
COPD (inflammation)	NR	× 6 weeks	COPD patients (n=40)	Reported	39548320
Healthy general population	NMN/NR	Various	Various	Insufficient — no validated indication	—

⚠️ What neither compound has proven: No validated indication for sarcopenia, frailty, anti-aging, cognitive preservation, longevity extension, or mortality/morbidity reduction in any population. Anti-sarcopenia claims are directly contradicted by an umbrella review of 10 NMN RCTs and 5 NR RCTs (PMID 40275690).

Evidence Grade Summary

Grade	Definition	NMN Findings	NR Findings
Confirmed	Replicated in ≥1 high-quality RCT with gold-standard endpoint	Insulin sensitivity improvement (prediabetic women, hyperinsulinemic-euglycemic clamp); blood NAD+ elevation dose-dependently	Blood NAD+ elevation dose-dependently (multiple RCTs)
Supported	Consistent signal in ≥1 RCT; clinically meaningful but not definitive	BP reduction in ≥60yo; lower limb function; drowsiness reduction; weight/lipid effects (MIB-626)	6-min walk in PAD; cerebral NAD+ in PD; BP subgroup effect
Reported	Preliminary signal; requires replication	Anti-inflammatory effects in COPD	Anti-inflammatory effects in COPD
Contested	Evidence conflicts or marketing exceeds data	NMN “direct precursor” bioavailability superiority; SLC12A8 human relevance	—
Gap	No human data or major evidence hole	Long-term safety (>12 weeks); brain BBB penetration; tissue-specific NAD+ distribution	Long-term safety; brain BBB penetration (PD signal exists but limited); tissue-specific NAD+ distribution; drug interactions

Critical PK Contradiction

NR Produces ~2.3× Greater Blood NAD+ Elevation Than NMN

Source: Nature Metabolism 2026 crossover trial (n=65, doi:10.1038/s42255-025-01421-8) and Berven et al. 2026 iScience (PMID 38979132).

This finding directly contradicts the dominant NMN marketing narrative — that NMN’s proposed “direct” intestinal absorption pathway (via SLC12A8) gives it superior bioavailability vs. NR. The 2026 head-to-head evidence does not support that claim.

Why the contradiction matters:

NMN’s oral bioavailability is unquantifiable because plasma NMN is not recovered after oral dosing (PMID 38561610)
Both compounds require enzymatic conversion upstream of NAD+ — neither is truly “direct”
Gut microbiome conversion to nicotinic acid/nicotinamide is a shared and substantial pathway for both (Shats et al., doi:10.1126/sciadv.adr1538)
The claimed SLC12A8 human NMN transport advantage has not been confirmed in humans (PMID 32694648)

What this does NOT mean:

NR is not clinically superior to NMN for any outcome — no head-to-head outcome trial exists
NMN’s insulin-sensitizing signal in prediabetic women (PMID 33888596) remains the strongest metabolic RCT finding for either compound and is specific to NMN
PM timing of NMN (PMID 35215405) remains a useful behavioral optimization

Formulation Stability

NR Stability

Aqueous solution: Stable ~83 days at 4°C (~95% intact); significant degradation at ambient (25°C) and elevated (40°C) temperatures
Gastric fluid (pH 1.2): Degrades to nicotinamide — a sirtuin-inhibiting byproduct
Intestinal buffer (pH 6.8–7.4): Also degrades to nicotinamide
Storage recommendation: Protect from moisture and heat; keep sealed in cool, dry environment
Novel salt forms: NR hydrogen tartrate and malate (US Patent 12,252,506, March 2025) are bioequivalent to NR chloride but offer improved manufacturability

NMN Stability

Aqueous solution: 93–99% intact over 7–10 days in mouse studies (PMC7238909) at room temperature
Temperature sensitivity: Significant degradation above ~28°C
Humidity: Degrades in high humidity conditions
Byproduct: Degrades to nicotinamide — a sirtuin-inhibiting byproduct at high doses
Storage recommendation: Refrigeration recommended by most manufacturers for long-term storage
Compounded aqueous formulations: Beyond-Use Dates typically 30–90 days

Sublingual Route — No Proven Advantage

Marketed to bypass first-pass hepatic metabolism. No large-scale head-to-head PK trial has demonstrated meaningfully superior absorption of sublingual vs. oral capsule NMN in humans. This claim is largely extrapolated from animal data. The sublingual route may also bypass the gut microbiome conversion pathway that contributes to systemic NAD+ elevation (Shats et al.).

Biomarker Tracking Protocol

Biomarker	Baseline	Month 1	Month 2	Month 3	Clinical Relevance
Fasting glucose	✓	—	✓	✓	Monitor metabolic effect (NMN-specific benefit in prediabetes)
Fasting insulin	✓	—	✓	✓	Monitor insulin sensitivity
HOMA-IR	✓	—	✓	✓	Insulin resistance index
hs-CRP	✓	—	✓	✓	Inflammatory load (CD38/NAD+ axis)
Resting HRV (RMSSD)	✓	✓ (day 14)	✓	✓	Autonomic resilience marker
Homocysteine (if ≥500mg NMN/NR)	✓	—	✓	✓	Methylation drain monitoring
Blood NAD+ (lab)	✓	✓ (day 14)	—	✓	PK confirmation — not definitive efficacy

⚠️ Note on metabolic benefits: Pooled meta-analysis (8 RCTs, n=342, PMID 39531138) found no statistically significant effect on fasting glucose, fasting insulin, HOMA-IR, or lipids in the general population. The Yoshino 2021 (PMID 33888596) insulin-sensitivity benefit is specific to postmenopausal women with prediabetes — it does not generalize to metabolically healthy individuals. Do not position NMN as a primary glucose- or lipid-lowering intervention.

NMN Readiness Baseline Acquisition Period

Do not assess NMN/NR efficacy before day 14 of consistent daily dosing.

Blood NAD+ plateaus at approximately day 14. HRV/RHR improvements — the most accessible Vitals-accessible signals — typically emerge in weeks 2–4 as NAD+-dependent SIRT1 activity normalizes autonomic function. Users who assess efficacy in the first week are measuring pre-plateau baseline, not supplement effect.

Expected timeline:

Days 1–7: No expected HRV/RHR change (blood NAD+ still rising)
Day 14: Blood NAD+ plateau — first meaningful biometric signal window
Weeks 3–4: HRV/RHR improvements emerge in responsive users
Week 8+: Additional metabolic effects (glucose handling in prediabetic users)

Dosing Protocol

500–600 mg/day oral NMN or NR — morning (circadian alignment with CLOCK/BMAL1 NAD+ cycle)
PM timing for NMN shows better drowsiness reduction in older adults (PMID 35215405) — consider afternoon dosing in this population
TMG 500–1000 mg alongside at high doses (methylation support; 1:1 ratio with NMN)
Resveratrol 500–1000 mg with fat source (SIRT1 allosteric activator; lowers activation energy threshold)
Fasted or fed — both fine for NMN/NR

⚠️ No long-term (>12-week) human safety data exists for NMN. All safety signals are from short-term trials (10 days to 12 weeks).

Tissue-Specific Effects

Skeletal muscle: Restores mtDNA copy numbers, suppresses ccf-mtDNA (inflammatory DAMP), improves insulin signaling and capillary density
Brain: NAD+ in occipital lobe declines sharply with age; reverses spatial memory impairment in Alzheimer’s models
Heart (ischemia/reperfusion): Pre-ischemic NMN: functional recovery 11% → 42%, infarct size 66% → 34%
Skin: Inhibits MAPK (TNF-α, IL-6 reduction), reduces MMP-1 collagen degradation; ~60 mm vs ~129 mm wrinkle measurement

Methylation Drain

NAD+ cleavage by sirtuins/PARPs → NAM → methylation via NNMT → SAMe depletion → elevated homocysteine, impaired DNA methylation, neurotransmitter synthesis disruption.

⚠️ TMG coadministration is mandatory at ≥500 mg/day NMN/NR chronically. Users with MTHFR polymorphisms should be particularly monitored. Check homocysteine at baseline and follow-up.

Regulatory Status

Region	NR	NMN
United States	GRAS (GRN 000635); NDI 825; continuously available as supplement	Reinstated Sept–Dec 2025 as lawful dietary supplement (NDI status) following federal court ruling (NPA lawsuit vs. FDA); was banned November 2022
EU	GRAS-equivalent via food safety framework	Novel Food — EFSA safety assessment required; not authorized for supplement sale
FDA/EMA approval	None for any indication	None for any indication

⚠️ Neither NR nor NMN is an FDA- or EMA-approved drug. Both are unregulated supplements in most markets. Quality control, contamination risk, and long-term pharmacovigilance are genuine concerns outside the clinical trial context.

Key Stacks

NMN/NR + GHK-Cu — Premier Longevity Synergy

GHK-Cu directly binds and activates SIRT1 (confirmed at Glu230 + Asn226); NMN/NR provides NAD+ substrate. Combined: enzyme expression + substrate both optimized → maximum SIRT1/PGC-1α/mitochondrial biogenesis. GHK-Cu’s STAT3 pathway requires NAD+ — NMN/NR enables it.

NMN/NR + PCC1 — The CD38 Unlock

Senescent cells → SASP → M1 macrophages → CD38 600× upregulated → NAD+ destroyed. PCC1 kills senescent cells → SASP eliminated → CD38 drops. NMN/NR then routes entirely to sirtuins and PARP. Sequence: PCC1 first to clear, then NMN/NR for maximum efficiency.

NMN/NR + SLU-PP-332 — Critical Pairing

SLU-PP-332 drives massive mitochondrial biogenesis (2.5× mtDNA increase). More mitochondria = exponentially more NAD+ required. Without NMN/NR: SLU-PP-332 drains the intracellular NAD+ pool → oxidative stress, fatigue, cellular exhaustion. NMN/NR is non-optional when running SLU-PP-332.

NMN/NR + Rapamycin — Complementary Anti-Aging Axes

Rapamycin induces mitophagy (clears damaged mitochondria), shifts NAD+/NADH to more oxidized ratio (improves SIRT1 efficiency). NMN/NR provides NAD+ substrate for SIRT1 and builds new mitochondria via PGC-1α. Different but synergistic: Rapamycin creates the optimal metabolic environment, NMN/NR provides the fuel.

Note: Rapamycin does NOT reduce CD38 expression — PCC1 is needed for that. NMN/NR is wasted on CD38 if senescent cell burden is high.

NMN/NR + Retatrutide — Lean Mass Protection

Retatrutide drives aggressive caloric deficit → muscle catabolism risk. NMN/NR maintains skeletal muscle mitochondrial NAD+ → prevents bioenergetic failure → activates SIRT1 → PGC-1α → oxidative fiber transition (protective).

NMN/NR + Imeglimin

Imeglimin repairs mitochondrial structural architecture; NMN/NR provides NAD+ to drive oxidative phosphorylation in those repaired mitochondria. Different interventions: Imeglimin fixes the hardware, NMN/NR runs the fuel.

Evidence Boundary / Claim Enforcement

⚠️ What Vitals coaching MUST NOT say — claim boundary enforcement:

The following claims are not supported by the current evidence base and must not be used in Vitals coaching, product content, or user-facing communications:

Prohibited Claim Category	Examples
Longevity/lifespan	”slows aging,” “extends lifespan,” “reverses aging”
Cognitive preservation	”prevents dementia,” “reverses cognitive decline,” “improves brain function”
Sirtuin activation	”activates sirtuins measurably,” “measurable SIRT1 boost”
Precursor superiority	”NMN is superior to NR for [any outcome],” “NR is better than NMN for [clinical endpoint]“
Mitochondrial function	”improves mitochondrial function (measurable),” “restores mitochondria”
DNA repair (consumer-accessible)	“directly repairs DNA,” “genome protection”
Drug interactions	”safe with [any specific medication]“
Anti-sarcopenia	”builds muscle,” “reverses sarcopenia,” “increases muscle mass” (umbrella review PMID 40275690: insufficient evidence)

Claim boundary test: If a claim sounds exciting, it probably exceeds the evidence. Use: “the current evidence suggests…” or “the strongest signal is…” rather than definitive efficacy statements.

Safe claim anchors:

“NR produced ~2.3× greater blood NAD+ elevation than NMN in a 2026 crossover trial” (PK fact)
“NMN improved insulin sensitivity (clamp-confirmed) in postmenopausal women with prediabetes” (Confirmed, PMID 33888596)
“NR improved 6-minute walk distance in PAD patients” (Supported, PMID 38871717)
“Both compounds are safe at studied doses in short-term RCTs” (Safety fact)

Implementation Algorithm Hooks

# Vitals NAD+ Precursor Monitoring — Evidence-Backed Tier
# Sources: PMID 33888596, 41901064, 29599478, 35215405, 36740954, 38871717, 38979132
# doi:10.1038/s42255-025-01421-8 (Nature Metabolism 2026 head-to-head)
 
from dataclasses import dataclass, field
from enum import Enum
from typing import Optional
import datetime
 
class Precursor(Enum):
    NR = "nicotinamide_riboside"
    NMN = "nicotinamide_mononucleotide"
    NAM = "nicotinamide"
    NONE = "none"
 
class Population_Risk(Enum):
    PREDIA_BETIC = "prediabetic"
    OLDER_65 = "older_adult"
    PARKINSONS = "parkinsons"
    PAD = "peripheral_artery_disease"
    COGNITIVE_MCI = "mci"
    HEALTHY_GENERAL = "general"
 
@dataclass
class PrecursorDosing:
    precursor: Precursor
    dose_mg: float
    frequency: str  # e.g., "once_daily", "twice_daily"
    timing: Optional[str] = None  # "morning", "afternoon" — PM timing for NMN per PMID 35215405
 
@dataclass
class MonitoringPlan:
    precursor: Precursor
    population_risk: Population_Risk
    log_blood_pressure: bool = True
    log_fasting_glucose: bool = False  # Only for prediabetic NMN users
    log_cgm: bool = False              # Only for prediabetic NMN users; requires clinical sign-off
    log_sleep: bool = True             # Consumer wearable data
    log_body_weight: bool = False       # Only if MIB-626 or specific NMN formulation
    log_nad_blood: bool = False         # Lab draw — not wearable-native
    expected_bp_effect_mmHg: float = -3.0  # NMN meta-analysis: -3.94 systolic ≥60 (PMID 41901064)
    expected_glucose_effect: Optional[str] = None  # From PMID 33888596 clamp study
    evidence_grade: str = "MODERATE"
 
def build_monitoring_plan(dosing: PrecursorDosing, population: Population_Risk) -> MonitoringPlan:
    """
    Build an evidence-backed biometric monitoring plan for a user on NR or NMN.
 
    Decision logic:
    - NMN + prediabetic/prediabetic risk → fasting glucose, HbA1c, consider CGM (PMID 33888596)
    - NR or NMN + older adult (≥65) → blood pressure + sleep metrics (PMID 41901064, 35215405)
    - NR + PAD → 6-min walk proxy via step count/HR recovery (PMID 38871717)
    - Any NMN + weight concern → weekly body weight log (PMID 36740954, MIB-626 formulation-specific)
    - NR head-to-head PK advantage: NR 2.3x greater blood NAD+ elevation (doi:10.1038/s42255-025-01421-8)
      → but no known downstream clinical outcome advantage; do NOT claim outcome superiority
    """
    plan = MonitoringPlan(
        precursor=dosing.precursor,
        population_risk=population,
    )
 
    if dosing.precursor == Precursor.NMN and population in (Population_Risk.PREDIA_BETIC, Population_Risk.OLDER_65):
        plan.log_fasting_glucose = True
        if population == Population_Risk.PREDIA_BETIC:
            plan.log_cgm = True  # Human sign-off required
            plan.expected_glucose_effect = "improved_insulin_sensitivity_clamp_demonstrated"
 
    if dosing.precursor == Precursor.NR and population == Population_Risk.PAD:
        plan.log_body_weight = True  # Monitor for any weight change alongside functional capacity
 
    # NMN PM timing observation (PMID 35215405) — flag as behavioral variable
    if dosing.precursor == Precursor.NMN and dosing.timing == "afternoon":
        plan.log_sleep = True  # PM NMN associated with reduced drowsiness
 
    return plan
 
# =============================================================================
# CLAIM BOUNDARY ENFORCEMENT — What Vitals Coaching MUST NOT SAY
# =============================================================================
UNSUPPORTED_CLAIMS = [
    "slows aging",
    "extends lifespan",
    "prevents dementia",
    "reverses cognitive decline",
    "activates sirtuins measurably",
    "superior to [other precursor] for [any outcome]",
    "improves mitochondrial function (measurable)",
    "directly repairs DNA (consumer-accessible)",
    "safe with [any specific medication]",
]
 
def check_claim_boundary(claim: str) -> bool:
    """
    Returns True if claim is evidence-supported.
    Returns False if claim exceeds the evidence base — do NOT use in coaching.
    """
    claim_lower = claim.lower()
    for prohibited in UNSUPPORTED_CLAIMS:
        if prohibited in claim_lower:
            return False
    return True
 
# Example usage:
# dosing = PrecursorDosing(Precursor.NMN, dose_mg=250, frequency="once_daily", timing="afternoon")
# plan = build_monitoring_plan(dosing, Population_Risk.OLDER_65)
# assert check_claim_boundary("NMN lowers blood pressure modestly in older adults") == True
# assert check_claim_boundary("NMN activates sirtuins and extends lifespan") == False

Active Clinical Trials to Watch

Trial	ID	Phase	Population	Status	Key Endpoint
NOPARK	NCT03568968	Phase 2	Early-stage PD (target n=400)	Ongoing	NAD+ repletion; disease modification — expected 2027–2028
N-DOSE	NCT05589766	Phase 2	PD patients	Ongoing	Optimal biological dose (OBD)
Niagen IV	NCT07251608	Phase 1	Healthy adults	Ongoing	Injectable NR safety
MINT	NCT05703074	N/A	Long COVID	Completed 2025	Quality of life
NADPARK	NCT03568968	Phase 1	Treatment-naïve PD (n=30)	Completed	Cerebral NAD+ (31P-MRS); safe
NR-SAFE	Not NCT-registered	Phase 1	PD patients	Completed	Safety at 3000 mg/day

Risks and Uncertainty

Risk Category	Detail
Long-term safety	No human RCT >12 weeks for NMN; no long-term pharmacovigilance data
Population gaps	No data in pregnant/lactating women, children, active cancer patients, or healthy adults <40
Drug interactions	No DDI studies with antihypertensives, hypoglycemics, statins, or anticoagulants
PARP interaction	Theoretical concern with chemotherapy agents and PARP inhibitors — no human cases documented
Quality control	Commercial supplement contamination/purity risks unaddressed in clinical trial literature
Brain penetration	Human BBB penetration not directly confirmed for NMN; cerebral NAD+ elevation shown for NR in PD
Tissue specificity	Blood NAD+ elevation may not reflect tissue-specific NAD+ distribution

Cancer Chemotherapy Interaction Risk

TL;DR: Preclinical evidence (Cancer Letters 2026, PMID 41724424) shows NMN/NR/NAM protected pancreatic cancer cells from oxaliplatin, 5-FU, and gemcitabine in vitro and in mice via NAD+-dependent DNA repair enhancement. No human clinical trial has confirmed this interaction. This is a preclinical contraindication signal requiring oncologist consultation — NOT a confirmed clinical contraindication.

Primary anchor: Nakazzi et al., Cancer Letters, April 2026 (PMID 41724424) — NMN, NR, and NAM all protected PDAC cells from oxaliplatin, 5-FU, and gemcitabine via three mechanisms: (1) tumor energy boost, (2) reduced tumor ROS, (3) suppressed DNA damage response. Potency ranking in PDAC: NMN > NR > NAM.

Most at-risk scenario: NMN + oxaliplatin, 5-FU, or gemcitabine in pancreatic/colorectal cancer. PARP inhibitor patients (olaparib, rucaparib, niraparib) at theoretical additional risk.

Critical gap: Zero prospective human RCTs have demonstrated actual chemotherapy efficacy reduction from NAD+ precursors. Three active trials: NCT03642990 (NR + chemo neuropathy), NCT06966583 (NMN + radioimmunotherapy NSCLC), NCT05732051 (NR + cancer recurrence).

Formulation risk: PMID 38935229 — commercial NMN label accuracy −100% to +28.6% deviation; unpredictable dosing adds uncertainty.

NAD+ precursor distinctions:

NMN: Strongest PDAC protection signal; best human safety data up to 1200 mg/day
NR: Moderate PDAC signal; may be less risky than NMN in this context; also showed benefit with paclitaxel/cisplatin neuropathy (PMID 35875690, 39128506)
NAM: Weakest PDAC signal; Preiss-Handler metabolic pathway; sirtuin-inhibiting at high doses may partially reduce the protective DNA repair mechanism

Vitals framing:

Non-cancer users: No change to current supplementation guidance
Active cancer patients on chemotherapy: ADVISORY — disclose all NAD+ supplements to oncologist before continuing; do not self-discontinue prescribed treatment
PARP inhibitor patients: Discuss with oncologist before using NAD+ precursors
Cancer survivors post-treatment: Theoretical risk is lower but unstudied

Vitals Knowledge Vault

Explorer

NMN NAD+