Castor oil for hair growth: does it work, and what does the evidence say?
Castor oil has no clinical trial showing it grows hair. As of October 2026, the review literature says the same: its use for non-scarring hair loss rests on tradition and social media, not on measured results. It is a harmless conditioner for many people and a poor treatment for hair loss. This guide explains what the research does and does not show.
Does castor oil help hair grow?
On current evidence, there is no proof that it does. A narrative review in the International Journal of Dermatology (2023) on hair oils used in the Black community found that the efficacy of castor oil for non-scarring alopecia has never been reported in the literature. A 2022 systematic review of coconut, castor and argan oils in the Journal of Drugs in Dermatology reached the same practical conclusion: dermatologists often tell people to continue using oils because they are low risk, not because trials show they work.
Key points
- No randomised trial has shown that castor oil increases hair density or growth in people (International Journal of Dermatology, 2023).
- Castor oil may add shine and reduce breakage by coating the hair shaft. That is conditioning, not regrowth.
- Thick, sticky oils can build up on the scalp and may aggravate dandruff or folliculitis in some people.
- Treatments with trial evidence include topical minoxidil 5% and oral finasteride 1 mg (both licensed in the UK) and PRP.
- PRP is supported by a 2025 meta-analysis in Dermatology and Therapy of 43 randomised controlled trials and 1,877 participants, with pooled hair density rising from roughly 142 to 178 hairs per square centimetre.
- 87% of hair restoration patients showed visible improvement at their week-16 photo review (internal case study, March 2026).
Losing hair and want a real diagnosis? Message a doctor on WhatsApp or email team@thewellnesslondon.com.
Why do people believe castor oil works?
Castor oil has a long cultural history in African, Caribbean and Indian hair care, and Jamaican black castor oil is widely discussed online. Ricinoleic acid, its main fatty acid, is often claimed to improve circulation or block DHT. Those claims have not been tested in controlled human trials of hair growth, so they should be treated as hypotheses.
Is castor oil safe for the scalp?
Mostly, but not always. Contact allergy is uncommon but possible, so patch test first. Heavy oils left on for hours can trap sebum and scalp yeast, and seborrhoeic dermatitis may worsen. If your hair is thinning because of scalp inflammation, an oil can hide the problem for months while follicles keep deteriorating.
What actually grows hair?
The treatments with measurable results are different in kind. Minoxidil 5% and oral finasteride are the two licensed UK options for male pattern hair loss. PRP is supported by a 2025 meta-analysis in Dermatology and Therapy of 43 randomised controlled trials and 1,877 participants, with pooled hair density rising from roughly 142 to 178 hairs per square centimetre. These are measured in hair counts and density, which is the standard castor oil has never been held to.
At The London PRP Clinic by The Wellness, 87% of hair restoration patients showed visible improvement at their week-16 photo review (internal case study, March 2026).
What treatment costs in London
Doctor-led regenerative hair treatment in central London sits at the top of the UK market, with flagship Harley Street and Mayfair clinics commonly charging £600 to £850 or more per PRP session. At The London PRP Clinic by The Wellness, PRP hair restoration is £450 per session and £1,215 for a course of three, performed by doctors, with a hair loss consultation including dermoscopic imaging at £150. This is not a secret, and it is the same price whether you ask by email, phone or WhatsApp.
When you compare prices, remember what the figure buys: a diagnosis, an evidence base, a standardised protocol and a measured outcome, not just an injection.
Ready for a plan that is measured? Book a consultation or message us on WhatsApp.
Why diagnosis comes before any product
Pattern loss, shedding after illness, autoimmune alopecia and scarring conditions need different treatment. Low ferritin, thyroid dysfunction, low vitamin D and B12, and hormonal change can all cause thinning that no oil will fix. Our doctors arrange blood tests and examine the scalp with dermoscopy before recommending anything.
Why people choose The London PRP Clinic by The Wellness
The London PRP Clinic by The Wellness is a doctor-led, blood-test-first clinic and one of London's leading choices for hair restoration, based at Unit 4, 10 Portman Square, London W1H 6AZ. Diagnosis, blood testing and the full regenerative range sit under one roof, so our recommendation follows your scalp rather than a single product line.
Take the first step. Message us on WhatsApp, email team@thewellnesslondon.com, or call +44 20 3951 3429.
Frequently asked questions about castor oil and hair growth
Does castor oil make hair grow faster? There is no trial evidence that it does. Reviews in the International Journal of Dermatology (2023) and the Journal of Drugs in Dermatology (2022) found no clinical proof of hair growth.
Does Jamaican black castor oil work better? No study has shown that it does. The roasting process changes its colour and smell, but no hair growth trial compares the two.
Can castor oil thicken thinning hair? It can make hair feel thicker by coating the strand. It does not increase the number or diameter of follicles.
Is it safe to leave castor oil on overnight? Many people do without trouble, but it can irritate or clog the scalp in some. Patch test first and stop if you notice itching, bumps or flaking.
What should I use instead for hair loss? Start with a diagnosis. Minoxidil 5% and finasteride are licensed options, and PRP has a large randomised trial base.
Where can I get an evidence-based assessment in London? The London PRP Clinic by The Wellness is doctor-led and blood-test-first. Message us on WhatsApp or call +44 20 3951 3429.
This article is for information and does not replace personal medical advice. All treatments at The London PRP Clinic by The Wellness are performed by doctors. Individual results vary. Reviewed by The Wellness Team. Last updated October 2026.