Research synthesisHigh evidenceModerate effect8 studies · 8 beneficial · 0 neutral · 0 harmful
Across 8 studies, all 8 reported beneficial effects of lavender on sleep quality, with effect sizes ranging from small to large and predominantly moderate to large. The most studied populations include adults with hypertension, patients with hematological malignancies undergoing chemotherapy, postmenopausal women, and older adults with sleep disorders, with common interventions involving inhaled lavender essential oil over 5–7 days.
- Studied populations: adults with hypertension, patients with hematological malignancies undergoing chemotherapy, postmenopausal women, older adults with sleep disorders, pregnant women
Caveats: Available evidence is overwhelmingly positive — clinical literature in this area is subject to publication bias (null-result studies are less likely to be published or indexed). Many studies used inhalation of lavender essential oil, and doses for oral forms are rarely reported, making it difficult to generalize across delivery methods. The median study duration was only 7 days, so longer-term effects remain unclear.
Generated Jun 13, 2026