Paraxanthine for Endurance
Verdict: Insufficient Evidence
Across 4 PubMed studies, the evidence for Paraxanthine in Endurance grades Tier U — unverified / insufficient. Research is still too limited to draw a firm conclusion.
U ⚫ U Unverified Insufficient Evidence
Why this grade7-layer evidence engine
⚖️
Scoring transparency
All scores computed by a 7-layer evidence engine — fully auditableRaw score 0.41
D
C
B
A
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← counter-evidence / ineffectiveeffective / strong evidence →
Final grade
U · Insufficient Evidence
Confidence
45%
Conflicting evidence
Evidence level
E3
Single high-quality meta-analysis
▸View the full decision path (audit trail)
- compute_raw_score — 加權公式: L2×0.30 + L3×0.25 + L5×0.25 + L11×0.10 + L1×0.10 = 0.406
- tier_from_score — 依分數區間映射至 tier letter
- apply_hec_rules — 無高階證據可裁決
- tier_strict_requirement_check — Tier 條件達標,未降階
- detect_disputes — 偵測到 0 個 hard + 1 個 soft dispute
- decide_status — 依 tier + dispute 結果決定 status
PubMed studies (4)L2 · primary research & systematic reviews
Paraxanthine provides greater improvement in cognitive function than caffeine after performing a 10-km run
Finding: No significant treatment effect on 10-km run time or any endurance/anaerobic capacity outcome (treatment x time p = 1.000, ηp² = 0.025); benefit was confined to post-run cognitive measures, not running performance
View on PubMed Paraxanthine Supplementation Increases Muscle Mass, Strength, and Endurance in Mice
Finding: Treadmill exercise performance +39% (p < 0.001), grip strength +17% (p < 0.001), soleus muscle mass +41% (p < 0.001) vs control — animal-only, not generalisable to humans
View on PubMed A Dose-Response Study to Examine Paraxanthine's Impact on Energy Expenditure, Hunger, Appetite, and Lipolysis
Finding: PX 200 mg increased resting energy expenditure vs placebo (p < 0.05); endurance / exercise performance NOT assessed — mechanistic only, indirect for endurance
View on PubMed Ergogenic effects of supplement combinations on endurance performance: a systematic review and meta-analysis of randomized controlled trials
Finding: Paraxanthine not evaluated in this 2025 endurance-supplement SR/MA — confirms absence of paraxanthine from current evidence-synthesis literature for endurance
View on PubMed Regulatory & authoritative positionsL4/L5 · FDA / EMA / NIH ODS / Cochrane / Mayo …
L4b EU EFSA
Cautious
Paraxanthine is manufactured by chemical synthesis. As synthetic paraxanthine was not consumed to a significant degree in the EU before May 15, 1997, it is a novel food according to Regulation (EU) 2015/2283. The identity of synthetic paraxanthine (1,7-dimethyl-3H-purine-2,6-dione) has been analytically verified. source↗