Legacy AI grade · Sources dated 2026-06-01. Not expert reviewed. Coverage is limited to the listed sources. About the new summary workflow
Procyanidin B-2 (Apple Polyphenol) for Hair Loss Telogen
There is no clinical evidence that procyanidin B-2 (apple polyphenol) treats telogen effluvium. Every human trial to date studied male-pattern hair loss, not this condition, so its effectiveness for telogen effluvium remains unproven.
Why this grade7-layer evidence engine
This pair earns an Unverified rating because not a single study has tested procyanidin B-2 in telogen effluvium patients. The only human data are two small, double-blind trials (PMID 11406858, n=29; PMID 11194183, n=29) of 1% topical procyanidin B-2 in men with androgenetic alopecia. Both reported modest hair-count gains, but they were run by one research group, funded by the apple-polyphenol supplier, and judged low quality. Applying them to telogen effluvium is off-label extrapolation, not proof.
The only link to telogen biology is a laboratory study (PMID 11841365) showing procyanidin B-2 down-regulates telogen-specific PKC isozymes and speeds the telogen-to-anagen shift in mice. That is a plausible mechanism, but a preclinical signal in mice cannot establish a clinical effect in people.
Authorities offer no support either. The US FDA recognizes apple polyphenol extract only as a safe food ingredient, with no drug or hair-growth approval, and the EU EFSA concluded a cause-and-effect relationship has not been established for proanthocyanidins. Mayo Clinic, Cleveland Clinic, Harvard, and the AAD never address it; the AAD notes telogen effluvium hair usually regrows once the trigger is resolved, making any benefit hard to distinguish from natural recovery.
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 = 0.376
- 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 — D 級條件未達 (需 E1-E3 negative；實際 E6)
- detect_disputes — 偵測到 0 個 hard + 1 個 soft dispute
- decide_status — 依 tier + dispute 結果決定 status