Peppermint essential oil for increased hair growth?
We see peppermint oil in many hair care products that promise fast hair growth. However, the evidence is still very preliminary. Always read the notes below carefully and decide for yourself how much or how little evidence you need in order to trust that it will work for you.
Overview: Peppermint oil was shown to induce an early anagen (growth) phase and to promote lengthening of hair follicles (which results in thicker diameter hairs)[1].
Evidence:
- Oh et al, 2014: Peppermint essential oil (diluted to 3% in a carrier oil) was used on mice and shown to be more effective than 3% minoxidil at promoting hair growth.
Important things to note about the study above:
1. This study was done in mice, so results may not be applicable to humans.
2. The oil was applied every day, 6 days a week, for 4 weeks on the animals’ shaven backs. Aka, it was easy to achieve complete coverage. If you have hair on your scalp (like most people), it might be difficult to ensure that you didn’t miss any spots.
3. The oil sat on the skin 24/7 and was not washed away. So basically, even if mice results can be applied to humans, you’d have to walk around with an oily scalp for weeks at a time to see the same results as in the study. That won’t be very obvious for people with baldness, but might look obvious for people with hair since their hair will look greasy.
4. This study did not show an increase in hair growth rate, only an earlier re-start of resting follicles. Aka, for hairs that are already growing, peppermint oil will not do anything. However, for resting follicles, the oil may stimulate them to become active earlier than they otherwise would have.
Side note: Both saline and Jojoba oil were used as aqueous and oil-based controls, respectively. Aka, jojoba oil alone did not produce an increase in hair growth. Something to think about next time you hear someone telling you that jojoba oil is a hair growth promoter…
Ingredients on the market that approximate study conditions:
You could use other carrier oils besides jojoba. However, that means you would not be following the study protocol, so there’s no way to tell what influence the tested oil will have on your results.
Peppermint oil reference: