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Longevity & Aging · Supplements

NAD+ precursors (NMN, NR) improves physical capacity

In plain terms: Do NAD+ booster supplements improve fitness?

Contested Longevity & Aging 💰 Industry COI noted🔬 Includes disconfirming

Part of: 🧪 nad+ precursors (nmn, nr)

RefutedContestedStrong support
consensus score 0.00

Unclear — evidence is mixed to negative; better studies find no real strength or endurance benefit.

📅 Last reviewed: 2026-07-14

Evidence ladder

How far up the ladder this claim has climbed. A high consensus on a low rung means "consistent so far," not "proven in people."

Top evidence so far: Human trials (RCT / n-of-1)

MechanismIn-vitroAnimalObservationalRCTMeta-analysis

How the studies fall

1 support 1 contradict 12 tested null 5 mixed · 19 sources, 2 independent groups

What the evidence shows

Whether NMN/NR improve endurance/strength/clinical metabolic outcomes - the honest nulls live here. Two meta-analyses find no significant functional benefit despite NAD elevation; positive signals are low-quality, industry-linked, or rest on secondary endpoints.

The evidence (19)

SourceGradeStanceQualityFinding
Shoji
2025 · Aging Cell
RCT tested-null low Werner-syndrome crossover: NR improved some progeroid/metabolic markers but evidence for physical-capacity gain limited and disease-specific
Prokopidis
2025 · J Cachexia Sarcopenia Muscle
meta-analysis tested-null moderate [FT-verified] FT: no sig effect SMI/grip/gait (CIs cross 0)
NIH 2020
ClinicalTrials.gov
RCT tested-null low Sole completed registered NMN organ-system trial; sparse registry base consistent with weak physical-capacity evidence
Lin KY
2026 · Lancet Neurol
RCT contradicts moderate 12-wk RCT: NR alone gave NO significant peak-VO2 improvement vs control (0.06 vs -0.05 L/min, p=0.188); only NR+exercise improved VO2 (i.e. the exercise, not NR). Null for NR as a standalone performance aid.
Yoshino
2021 · Science
RCT mixed moderate Imai-lab NMN RCT: improved muscle insulin sensitivity in prediabetic women but no change in body weight, lipids or other endpoints
Igarashi
2022 · NPJ Aging
RCT mixed low NMN 250mg up to 12wk raised NAD+ in older men; only nominal gait-speed/left-grip gains, no body-composition change - weak, secondary-endpoint signal
Ahmadi
2023 · JCI Insight
RCT tested-null moderate Crossover in CKD: NR (and CoQ10) did not improve VO2peak or work efficiency vs placebo; NR lowered submaximal VO2 - null for aerobic capacity
Dollerup
2020 · J Physiol
RCT tested-null moderate NR did not improve muscle mitochondrial respiration, content or morphology in obese insulin-resistant men
Orr
2024 · GeroScience
RCT tested-null moderate NR 1g/d in MCI raised NAD+ but did not improve cognition; walking speed improved only in placebo (practice effect) - null for function
Wen J
2024 · Cureus
RCT tested-null low Systematic review/MA of 10 RCTs (437 participants, NMN 150-1200 mg/day): improvements in grip strength and physical-performance parameters were NON-SIGNIFICANT - human evidence that NMN does not meaningfully improve physical capacity.
Liao
2021 · J Int Soc Sports Nutr
RCT mixed low [FT-verified] FT n=12/arm single team no COI decl; improved submax thresholds NOT VO2max/peak; weaker than supports
Christen
2026 · Nat Metab
RCT tested-null moderate Head-to-head RCT of three NAD+ precursors: differential NAD+ raising but clinical/functional translation modest - precursor pharmacodynamics outpace outcomes
McDermott
2024 · Nat Commun
RCT supports moderate NICE RCT n=90 PAD: 6mo NR improved 6-min walk vs placebo (+17.6m; +31m in >=75% adherent); resveratrol added no benefit - positive physical-capacity signal
⚠️ correction-on-file (Crossref) - kept, corrigendum not retraction
Zhang
2025 · Crit Rev Food Sci Nutr
meta-analysis tested-null moderate [FT-verified] 12 studies/513 raises NAD but clinical outcomes NS; authors call benefit exaggerated
Morifuji
2024 · GeroScience
RCT mixed moderate NMN 250mg/12wk: primary stepping-test endpoint NULL; only secondary 4m-walk and sleep improved
Hsu YJ
2025 · Nutrients
animal mixed moderate Aged mice: NMN 300 mg/kg/day for 6 weeks improved maximal strength and aerobic endurance - preclinical support for a performance benefit not reproduced in the human RCT/MA evidence.
Berven
2023 · Nat Commun
RCT tested-null low NR-SAFE: high-dose NR safe in PD, raised NAD+; UPDRS change confounded by levodopa timing - no robust functional/capacity benefit
Norheim
2024 · Nat Aging
RCT tested-null moderate NR vs placebo in COPD: no improvement in airway inflammation; functional/capacity endpoints not benefited
Lin
2025 · GeroScience
RCT tested-null low Pilot RCT: NR+exercise NOT superior to placebo+exercise for systolic BP/PWV in older hypertensives; exercise-capacity benefit not demonstrated

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