Rosemary oil for thinning hair: what one trial shows and how safe it is

Name: Rosemary oil for thinning hair: what one trial shows and how safe it is
Creator: MenoWoman

Rosemary oil is a plant essential oil that some people rub into the scalp for thinning hair. One small trial suggested it worked about as well as low-strength minoxidil, but the evidence is limited and has not been tested well in menopausal women.

Researched by the MenoWoman team. Edited by Marcela Sat. Updated 7 November 2026. We may earn from links.

See a doctor or dermatologist if hair loss is sudden, patchy, or comes with scalp pain, redness or scaling, or if you also feel very tired or notice weight changes.

What it is

Rosemary is a cooking herb. Rosemary essential oil is a concentrated extract from the plant. People apply it to the scalp, usually mixed with a carrier oil.³

Suggested ways it might work include effects on inflammation and blood flow. Researchers do not yet know how, or whether, it works.^3,2

What the research shows

Most interest comes from one trial published in 2015. It compared rosemary oil with 2% minoxidil in 100 people with pattern hair loss, 50 in each group, for 6 months.¹

Neither group improved at 3 months. At 6 months, hair counts rose in both groups, with no clear difference between them.¹ The published abstract does not say how many participants were women.

The trial had no placebo group. So it cannot show how much of the change was due to the oil itself.¹

A 2025 review of herbal hair remedies called rosemary promising. It noted that much of the supporting work was in mice and short-term. It said more research is needed.²

A dermatologist quoted by Cleveland Clinic says it may help a little, especially if hair loss has just started. She warns not to expect dramatic results with long-standing hair loss.³

For treatments with stronger evidence, see minoxidil.

Safety and who should be careful

Essential oils are strong and can irritate the skin. Cleveland Clinic advises diluting rosemary oil in a carrier oil and testing a small patch of scalp first.³

Using too much can cause redness, burning and scalp inflammation. Stop if irritation happens and see a dermatologist.³ In the 2015 trial, itchy scalp was common in both groups, but less so with rosemary.¹

Do not swallow rosemary essential oil. It can be toxic even in fairly small amounts.⁴ It is not advised in pregnancy or while breastfeeding.^3,4

If you have eczema or sensitive skin, be extra careful.³

How it is available

Rosemary oil is sold widely as an essential oil and in shampoos, serums and hair oils. It is a cosmetic product in most countries, so it is not tested or approved as a hair loss medicine. Strength and purity vary between products.

The bottom line

Rosemary oil is cheap and widely available, and some people like using it. But the evidence rests mainly on one small trial without a placebo group.^1,2

It has not been well tested in women with menopausal hair thinning. Results, if any, take months to appear.³

If your hair is thinning, a doctor or dermatologist can check for causes and discuss minoxidil, which has stronger evidence in women.

What it is used for: evidence rated

Option	Evidence	What the research shows
Thinning hair	Weak evidence	One small trial without placebo found similar results to 2% minoxidil after 6 months; not tested well in menopausal women.^1,2
Scalp itch and dandruff	Weak evidence	In the same trial, dandruff did not change; itch was less common than with minoxidil.¹

Ratings explained: how we rate. Always talk to a doctor or pharmacist before starting a medicine or supplement.