Is Lavender a Hormone Disruptor? What the Research Shows

Lavender is the poster child of “natural” and “calming,” so it’s surprising to see it in conversations about hormones, and to see people ask: is lavender a hormone disruptor? The research is real, but it’s also easy to overstate. Here is what’s actually been found, and how much weight it can carry.

The 2007 case reports

In 2007, Henley and colleagues published a report in the New England Journal of Medicine describing three boys with prepubertal breast growth. The cases were linked to products containing lavender and tea tree oil. In each case, the breast growth went away when the boys stopped using the products.

That’s a striking pattern, and it’s the reason this question exists. But it’s a case report: three children, observed individually. Case reports can raise a flag. They can’t tell you how common an effect is, or establish what caused it.

The 2018 lab findings

A decade later, researchers at the National Institute of Environmental Health Sciences (NIEHS) followed up. Ramsey and colleagues presented findings at the Endocrine Society’s 2018 meeting. They tested 8 compounds found in lavender and tea tree oil in lab (cell) tests, and the compounds showed estrogenic and/or anti-androgenic activity.

That means that in a dish, these compounds interacted with hormone pathways in ways that mimic estrogen or block androgens. It’s useful mechanistic evidence that fits the case reports.

So, is lavender a hormone disruptor? How strong the evidence is

Be precise here, because this is where articles tend to go wrong.

• What exists: a few case reports, plus laboratory studies on cells.
• What doesn’t: population studies that follow large groups of people using lavender products and track hormone outcomes.

So the honest summary is: there is a plausible biological signal and a few suggestive cases, but no population-level evidence showing how often, or at what exposure, lavender products affect anyone. A lab finding doesn’t mean a lotion does the same thing on skin, and the case reports can’t tell us about typical use.

Neither “lavender is dangerous” nor “lavender is fine, case closed” is supported. The evidence sits in between, which is why we describe it as linked to concern rather than as a proven cause.

Who should be more careful?

The cases involved young children, so that’s where caution makes the most sense. If you’re choosing bath products, lotions or sleep sprays for a baby or young child, a plain fragrance-free option avoids the question altogether. In our data, CeraVe Baby Wash and Shampoo scored 8 out of 10 with no hormone flags. Formulas change; check the label on the bottle you buy.

If you’re pregnant, nursing or managing a hormone-related condition, bring it up with your doctor rather than relying on a blog post.

For most adults using a lavender product occasionally, the evidence doesn’t justify alarm. It does justify knowing what’s in your daily products.

Where lavender hides

Lavender oil appears in more places than a bottle labeled “lavender.” It can be part of the scent in lotions, body washes, deodorants, hair products and sleep mists marketed as natural or calming. On a US label, it can also be folded into a single word: “fragrance” or “parfum.”

That second part matters. In the US, a blend of many chemicals can be listed as just “fragrance” under trade-secret protection. You often can’t tell from the label whether lavender, or anything else of concern, is in the mix. We cover that in What “fragrance” on a label can hide.

It’s also why undisclosed fragrance was the most common hormone flag in our scans. Of 133 products, 65 (49%) had at least one hormone flag, and fragrance accounted for most of them. Our sample was best-sellers we chose, not a random slice of the market.

Why this isn’t a reason to panic

A hormone-related finding in a petri dish tells researchers where to look. It doesn’t tell you what happens when a diluted oil sits in a lotion and touches skin for a short time. The 2007 case reports involved three boys; the 2018 work was done in cells. Both are worth taking seriously as early signals, and neither is a population study.

What to do

You don’t have to purge your cabinet. A few steps cover the reasonable ground:

• For babies and young children, choose fragrance-free products. “Unscented” usually isn’t the same thing; it can mean a masking fragrance was added to cover base smells.
• Read for plant oils in the ingredient list, including lavender and tea tree.
• Prioritize daily, leave-on products like body lotion over a wash-off product you use occasionally.
• Keep it in proportion. The evidence is case reports and cell studies. A flag is a reason to look closer, not proof of harm.

For a wider look at what the term “natural” does and doesn’t guarantee, see What is clean beauty?.

Sources

• NIH: Lavender, tea tree oils may cause breast growth in boys
• Endocrine Society: Chemicals in lavender and tea tree oil appear to be hormone disruptors (2018)
• ToxFree scans of 133 products, September 23 – October 5, 2026, re-scored October 6, 2026

Educational information, not medical advice. Formulas change, so check the label on the product you buy.