Ashwagandha for Anxiety
Standardized ashwagandha root extract (300-600 mg/day for 8-10 weeks) consistently reduced anxiety and stress scores across recent meta-analyses, but the trials are small, often industry-funded, and highly inconsistent, so the effect size is uncertain and major psychiatric bodies have not endorsed it.
Why this grade7-layer evidence engine
Three 2024-2025 systematic reviews and meta-analyses point the same direction: ashwagandha lowered anxiety versus placebo. PMID 41140145 found a significant outlier-corrected SMD of -1.13, PMID 39083548 reported a Hamilton Anxiety reduction of -5.96 points, and PMID 39348746 found reduced stress, anxiety, and cortisol with no added benefit above 600 mg/day. NIH ODS and Mayo Clinic echo this, noting benefit for stress and anxiety.
The grade stays at Preliminary (B) rather than higher because the evidence is fragile. PMID 39083548 showed extreme heterogeneity (I-squared = 98%), and the supporting RCTs (PMID 32021735 and PMID 31728244) are small (n=58 each) and industry-funded. Most trials measured perceived stress rather than diagnosed anxiety disorders.
It is flagged Disputed because authorities disagree: Cleveland Clinic states the evidence is unclear, and neither the APA nor the ADAA lists ashwagandha for anxiety. NIH ODS also notes rare liver-toxicity reports, so it is a plausible adjunct, not a proven or first-line treatment.
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 = 0.677
- tier_from_score — 依分數區間映射至 tier letter
- apply_hec_rules — 高品質 SR/MA 顯示 positive (3 篇 > 0 negative)
- tier_strict_requirement_check — Tier 條件達標，未降階
- detect_disputes — 偵測到 1 個 hard + 1 個 soft dispute
- decide_status — 依 tier + dispute 結果決定 status