Legacy AI grade · Sources dated 2026-07-25. Not expert reviewed. Coverage is limited to the listed sources. About the new summary workflow
Methylene Blue for Aging
There is no human trial evidence that methylene blue slows aging or extends lifespan, and major regulators classify it as a prescription drug with serious interaction risks, not a longevity supplement. The current evidence base actively argues against its use for anti-aging.
Why this grade7-layer evidence engine
This claim earns a Counter-Evidence (D) grade because not a single human trial has tested whether methylene blue affects biological aging, age-related disease, or mortality. The strongest human study (Pang 2021, PMID 33091706) was an open-label RCT in 248 elderly surgical patients showing a single 2 mg/kg IV dose cut early postoperative cognitive dysfunction (OR 0.30). That is acute perioperative protection and cannot be stretched into a claim about chronic anti-aging supplementation.
Every 'longevity' signal rests on mechanism and animal work. A 2021 review (PMID 34943887) synthesizes redox and senescence effects but explicitly notes no human longevity trials exist, while skin-cell (Xiong 2017, PMID 28559565) and aged-mouse brain (Zheng 2020, PMID 32008150) data are preclinical only. Critically, the highest-quality controlled aging study in mice (Poudel 2024, PMID 38535998) found no in vivo benefit on skeletal aging despite favorable cell-culture results.
Authorities reinforce the negative verdict. The FDA, EU EMA, and UK MHRA all license methylene blue only as a prescription antidote for methaemoglobinaemia, with an FDA warning of serious or fatal serotonin syndrome when combined with serotonergic drugs; the WHO lists it solely as an emergency antidote. Specialty aging societies state plainly that no supplement has been shown in well-designed human trials to slow biological aging, and Harvard Health does not endorse the anti-aging use.
Scoring transparency
All scores computed by a 7-layer evidence engine — fully auditable▸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 = 0.505
- tier_from_score — 依分數區間映射至 tier letter
- apply_hec_rules — 高品質 SR/MA 顯示 positive (1 篇 > 0 negative)
- tier_strict_requirement_check — | C→D 因 scope.conflation_risk=true 且 L11 獨評較低 (B7-2 tier cap)
- detect_disputes — 偵測到 0 個 hard + 0 個 soft dispute
- decide_status — 依 tier + dispute 結果決定 status