Chromium for PCOS
Chromium may modestly nudge a few metabolic markers in PCOS, but the evidence is weak and disputed, and no health authority recommends it for the condition. It is not a substitute for proven first-line care, and better-supported options such as inositol exist.
Why this grade7-layer evidence engine
The supportive signal comes almost entirely from small trials of chromium picolinate (200-1000 mcg/day). Meta-analyses report modest drops in BMI (about 0.87-1.13 kg/m2), fasting insulin (roughly -1.3 mIU/L) and free testosterone (PMID 30180497, PMID 29307112, PMID 28595797, PMID 41067797), echoed by individual RCTs (PMID 26279073; PMID 24639797, where chromium roughly matched metformin). But two foundational pilots were tiny and underpowered (PMID 16730719, n=5; PMID 16359984, n=6), and the meta-analyses largely re-pool the same single-center Iranian trials rather than independent evidence streams.
The grade lands at weak (C) and disputed because the wins are on surrogate markers, not the outcomes that matter most in PCOS such as ovulation, pregnancy or live birth, and effects on fasting glucose, total testosterone and lipids were null. No large independent RCT or Cochrane review exists.
Regulators and clinicians are notably cautious. The FDA calls a chromium-insulin link 'highly uncertain'; EFSA found no evidence of benefit and does not deem chromium essential; NIH ODS rates its weight effects as clinically negligible; Harvard is unsupportive and Cleveland Clinic skeptical. Crucially, the 2023 international PCOS guideline (Endocrine Society/ASRM) discusses inositol but does not mention chromium, so it remains, at best, an unproven adjunct.
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 = 0.556
- tier_from_score — 依分數區間映射至 tier letter
- apply_hec_rules — 高品質 SR/MA 顯示 positive (2 篇 > 0 negative)
- tier_strict_requirement_check — | B→C 因 scope.conflation_risk=true 且 L11 獨評較低 (B7-2 tier cap)
- detect_disputes — 偵測到 1 個 hard + 0 個 soft dispute
- decide_status — 依 tier + dispute 結果決定 status