CBD may promote hair growth, but other cannabinoids could cause hair loss | Research

The takeaway

A review found that topical CBD at the right concentration may promote hair growth, with one trial reporting a 93.5% increase in hair count, but some cannabinoids had the opposite effect.

People interested in CBD for hair loss, dermatologists, and anyone curious about topical cannabinoid applications.

93.5% increase in hair count with daily topical CBD over 6 months

What the researchers found

CBD appeared to promote hair growth, but the effect was concentration-dependent. At high concentrations (10 micromolar or above), CBD may actually cause hair loss. One trial found that daily application of a CBD-rich topical extract for six months increased nonvellus hair count by approximately 93.5% in 35 patients with androgenetic alopecia.

Why it matters

Hair loss affects millions of people, and the growing availability of CBD products has led to consumer interest in cannabinoid-based hair treatments. Understanding which cannabinoids help versus harm is important before these products proliferate.

The numbers in context

93.5% increase in nonvellus hair count in 35 patients (28 males, 7 females) after 6 months of daily topical CBD application. Each application contained 3-4 mg of CBD. The extract was 10.78% CBD and 0.21% THC.

How the study worked

Comprehensive structured search of PubMed and Google Scholar (June 2022) reviewing studies on cannabinoid effects on hair growth and loss.

What this study cannot tell us

The key trial was a single uncontrolled study with 35 participants. The review included limited clinical evidence. Optimal CBD concentrations for hair growth have not been established in controlled trials.

How to read the evidence

Review drawing primarily on one uncontrolled clinical trial with 35 participants and limited preclinical data.

When this study was published

Published in 2022, literature search through June 2022.

The bigger picture

The concentration-dependent effect of CBD on hair illustrates a broader pattern in cannabinoid research: dose and formulation matter enormously, and more is not necessarily better.

Questions still open

What is the optimal CBD concentration for hair growth? Do other phytocannabinoids in full-spectrum products counteract CBD's hair-promoting effects?

Common questions

Can CBD help with hair loss?

One trial reported a 93.5% increase in hair count after 6 months of daily topical CBD application, but this was an uncontrolled study and more research is needed.

Can cannabinoids cause hair loss?

Yes. While CBD at low concentrations appeared to promote growth, several other phytocannabinoids and CBD at high concentrations (above 10 micromolar) were associated with hair loss in the reviewed studies.

Read the original research

A cannabinoid Hairy-Tale: Hair loss or hair gain?

Journal of cosmetic dermatology, 21(12), 6653-6660

View on PubMed ↗Publisher’s paper ↗

Citation

Gupta, Aditya K; Talukder, Mesbah. (2022). A cannabinoid Hairy-Tale: Hair loss or hair gain?. Journal of cosmetic dermatology, 21(12), 6653-6660. https://doi.org/10.1111/jocd.15427