Botanicals & Herbs

Lavender

Also known as: Lavandula angustifolia, Lavender oil, English lavender

The calming classic — real anxiety and sleep evidence in aromatherapy, plus one controversial endocrine question for young boys.

By IngredientWiki Editorial Team
Fact-checked by IngredientWiki Editorial Team
Updated 2026-09-26
3 min read

In short

Lavender (Lavandula angustifolia) is the Mediterranean shrub whose essential oil is the most studied aroma in the world for anxiety and sleep. The evidence is genuinely good for aromatherapy: meta-analyses find lavender inhalation reduces anxiety in medical settings, and oral capsules of standardized lavender oil (Silexan) have trial support comparable to low-dose anxiolytics for generalized anxiety. The controversy concerns a 2007 case series linking lavender oil products to breast growth (gynecomastia) in three prepubertal boys, with cell studies suggesting weak endocrine activity in some components; subsequent reviews consider the risk uncertain, and regulators have not restricted adult use. Contact allergy to oxidized lavender oil is the other documented concern.

Most-studied aromatherapy oil for anxiety and sleep
Silexan (oral lavender oil): anxiety trial evidence
2007 gynecomastia case series — endocrine question unresolved
Contact allergy possible with oxidized oil

What is Lavender?

Lavender is aromatherapy's flagship — the smell of calm, and one of the few botanicals whose anxiety evidence survives systematic review. Inhaled, it measurably lowers anxiety before surgery and exams; swallowed as standardized oil, it performs respectably against low-dose drugs for generalized anxiety, which is why Germany licenses it. But lavender also carries a specific, unresolved question mark: a 2007 report of breast development in three young boys using lavender products, backed by weak endocrine signals in cell studies. The risk profile remains debated, and adults' use is unaffected — but the episode is exactly the kind of uncertainty a careful consumer should know about.

Where it comes from

Natural sources

Flowering tops of Lavandula angustifolia, native to the Mediterranean
Essential oil rich in linalool and linalyl acetate
Used since antiquity for bathing, sleep, and wounds

How it's made

Essential oil for inhalation/topical use; oral standardized preparations (Silexan, 80 mg) for anxiety.

What it does in products

Benefits

Anxiety reduction

strong evidence

Meta-analyses of inhalation trials and randomized studies of oral Silexan find significant anxiety reduction versus placebo, with Silexan effects comparable to low-dose lorazepam in one head-to-head trial.

Sleep quality

moderate evidence

Trials in insomnia and in hospital settings report improved sleep quality and reduced wakefulness with lavender aromatherapy.

Mild pain and tension relief

emerging evidence

Aromatherapy massage studies report reduced pain intensity and tension; effects are partly attributable to massage itself.

Side effects & safety

Allergic contact dermatitis (uncommon)Typically from oxidized oil in leave-on products; patch-test.

Nausea at high oral doses (uncommon)Silexan trials report mild GI effects.

Safety considerations

Topical aromatherapy use generally considered safe in low dilution; oral use not recommended without clinician input.
CNS depressants — additive sedation with benzodiazepines, alcohol, sleep aids
No significant drug-interaction signals with Silexan in trials
Not for: Prepubertal boys — endocrine question unresolved; many authorities advise avoiding concentrated daily topical use
Not for: Known lavender oil allergy

How it's used

In supplements

Oral: 80 mg/day Silexan (standardized oil) for anxiety. Aromatherapy: 2–4 drops in a diffuser, or 1–5% dilution for topical use.

In skincare

0.1–1% in cosmetics for fragrance; higher only with patch-testing.

Regulatory status

Sold as a dietary supplement and cosmetic ingredient; Silexan is a licensed medicine in Germany for anxiety.
GRAS (generally recognized as safe) for food use.
INCI name on cosmetic labels: Lavandula Angustifolia (Lavender) Oil.
Assessed as safe in cosmetics with sensitization caveats.

The Silexan evidence

Silexan is a patented oral preparation of lavender oil (80 mg). Multiple randomized trials in generalized anxiety and subsyndromal anxiety show significant symptom reduction, with a 2010 comparison to lorazepam finding similar efficacy without sedation — an unusual result for a botanical. A 2019 meta-analysis confirmed the effect across studies, cementing lavender's place as the best-evidenced oral anxiolytic herb.

The gynecomastia question

A 2007 NEJM letter reported three boys, ages 4–10, who developed breast tissue while using lavender-containing products, reversing on discontinuation. Cell assays suggested lavender oil components had weak estrogenic and anti-androgenic activity. Later analyses have disputed the exposure estimates and questioned causality; the endocrine activity is far weaker than pharmaceutical hormones. The question remains open, with most authorities advising against concentrated daily lavender products in prepubertal boys.

Frequently asked questions

Does lavender really work for anxiety?

For mild-to-moderate anxiety, the evidence — both inhaled and oral — is among the best of any botanical. Effects are modest compared to prescription drugs but consistent.

Is lavender oil safe for children?

Aromatherapy diffusion at low doses is generally considered fine. The endocrine question concerns concentrated daily topical use in prepubertal boys — the area of genuine uncertainty.

Why do I get a rash from lavender products?

Lavender oil oxidizes over time into allergenic compounds; older oils and leave-on products are the usual culprits. True lavender allergy is confirmed by patch testing.

The bottom line

Lavender is the best-evidenced botanical for mild anxiety — with one unresolved pediatric endocrine question that neither cancels its adult benefits nor deserves to be dismissed.

References

Oral lavender oil (Silexan) for anxiety: meta-analysis. PubMed Central. https://pubmed.ncbi.nlm.nih.gov/31639105/
Prepubertal gynecomastia linked to lavender oil. New England Journal of Medicine. https://pubmed.ncbi.nlm.nih.gov/17267908/
Lavender — NCCIH. NCCIH. https://www.nccih.nih.gov/health/lavender