Valerian for Insomnia
Valerian earns only a weak (Tier C) rating for insomnia: pooled trials suggest it may modestly improve how rested people feel, but it does not measurably shorten the time to fall asleep or extend sleep duration. Major sleep specialists actively recommend against relying on it.
Why this grade7-layer evidence engine
The grade rests on three meta-analyses that all point the same, limited direction. Bent 2006 (PMID 17145239, n=1093) found roughly 1.8 times higher odds of self-reported sleep improvement, and Fernandez-San-Martin 2010 (PMID 20347389) echoed a modest subjective benefit (RR 1.37). But the same Fernandez analysis showed essentially no objective effect, with sleep latency improving by just 0.70 minutes. Shinjyo 2020 (PMID 33086877, n=1065) again found only subjective gains.
Several quality problems hold the score at weak rather than moderate. Trials varied widely in dose, valerian preparation, and duration; most carried significant methodological limitations; and Bent 2006 flagged possible publication bias. In short, the strongest, most measurable outcomes (time to fall asleep, total sleep) show no clear effect, while the positives are softer self-reported impressions.
Authorities are split, which is why this claim is treated as disputed. The WHO monograph supports valerian as a mild sedative, and the Mayo Clinic notes it may modestly improve sleep quality (though not duration or severity, and only after weeks). The FDA recognizes it only as a flavoring, not a sleep treatment, and the American Academy of Sleep Medicine explicitly suggests clinicians not use valerian for insomnia. It is also flagged for interactions with sedatives and alcohol, so caution is warranted.
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 = 0.539
- 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 + 0 個 soft dispute
- decide_status — 依 tier + dispute 結果決定 status