Magnolia Bark Extract for Stress
Magnolia bark may modestly blunt stress and cortisol in some people, but the human evidence is thin, inconsistent, and drawn almost entirely from a single industry-funded combination product, so it cannot be considered a reliable way to manage stress.
Why this grade7-layer evidence engine
The human trials are few, small, and study "Relora"—a proprietary blend of magnolia plus Phellodendron bark—rather than magnolia alone, so any magnolia-specific effect cannot be isolated. The most favorable trial (PMID 23924268, n=56) reported an 18% drop in salivary cortisol and improved mood versus placebo, but it was funded by the supplement's manufacturer. A second randomized trial in healthy women (PMID 18426577, n=40) found only a reduction in momentary state anxiety, with no significant change in cortisol, sleep, or appetite, and a small weight-management trial (PMID 16454147, n=26) showed only an exploratory cortisol trend.
The supporting mechanism is preclinical: honokiol, a magnolia compound, acted like an anti-anxiety agent through GABA-A pathways in mice (PMID 9720634), an effect never confirmed against a human stress endpoint.
Because every human trial used a combination product, samples were tiny, cortisol results conflicted, and the funding was industry-tied with no meta-analysis available, the evidence rates only weak. No regulator (FDA, EFSA, NHS, WHO) and no major clinical body (NIH ODS, Mayo Clinic, Cleveland Clinic, Harvard Health, APA) endorses magnolia bark for stress; the FDA's only relevant action was a warning letter over unapproved drug claims.
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 = 0.453
- 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 — Tier 條件達標，未降階
- detect_disputes — 偵測到 0 個 hard + 1 個 soft dispute
- decide_status — 依 tier + dispute 結果決定 status