Plant extracts
Rosemary oil and extract
Also listed as rosmarinus officinalis leaf oil, rosemary essential oil, rosemary extract
Popular as 'natural minoxidil' on the strength of one small trial with no placebo group. Pleasant scent; hair-growth benefit unconfirmed.
What it is
Rosemary essential oil is widely promoted for hair growth. The claim traces to a 2015 trial in which 100 people with pattern hair loss used rosemary oil or 2% minoxidil for 6 months: both groups gained some hair, with no difference between them.
That trial had no placebo arm, used low-strength minoxidil, and has not been independently repeated. Rosemary extracts in skin and body products are mostly there as antioxidants that protect the formula.
How strong is the evidence?
Weak evidenceOne small randomised comparison without placebo found similar hair-count changes to 2% minoxidil at 6 months. Without a placebo group it cannot show that either did better than nothing, and it tested a leave-on oil, not a rinse-off shampoo.
What it's used for, checked
Regrows hair as well as minoxidil
UnprovenOne small trial, no placebo, against the weaker 2% minoxidil.
Works in shampoo
UnprovenRinse-off contact is brief; the trial used a leave-on product.
Antioxidant to protect the product
Holds upA common and reasonable formulation use of rosemary extract.
Who should be careful
- Undiluted essential oil can irritate or sensitise the scalp; patch-test leave-on products.
- Keep essential oils away from eyes and out of reach of children.
- For progressing hair loss, see a clinician: proven treatments exist and early treatment works best.
The studies
Every citation is checked against its PubMed record.
- Rosemary oil vs minoxidil 2% for the treatment of androgenetic alopecia: a randomized comparative trial. Panahi Y, Taghizadeh M, Marzony ET, Sahebkar A · Skinmed · 2015 · RCT (comparative, no placebo)
100 people with pattern hair loss used rosemary oil or 2% minoxidil for 6 months. Neither changed at 3 months; both had a significant rise in hair count at 6 months with no difference between groups, and scalp itch was more common with minoxidil.