New: A treatment designed for rosacea-prone skin

New: A treatment designed for rosacea-prone skin

By edit
Face care
Stage of skin ageing
Body and hair care
By concern
Skin diagnostic
All Topics
Huile de ricin et calvitie.

Is castor oil effective in slowing down baldness?

Associated with significant hair loss, baldness is a hair problem that primarily affects men. Known for stimulating hair growth, could castor oil be a solution to slow down baldness?

Published February 14, 2024, by Pauline, Head of Scientific Communication — 5 min read

What is baldness?

Baldness is characterised by excessive hair loss. This phenomenon is characterised by the weakening of the activity of the hair follicles. As a result, hair decreases in certain areas of the scalp. Generally, baldness occurs between one's twenties and forties. This hair issue primarily affects men and is very widespread. It is estimated that about 30% of men show signs of alopecia at 30 years old, 50% at 50 years old, and 80% at 70 years old.

Also known as androgenetic alopecia, the most common form of baldness is linked to a hormonal cause. Both women and men produce androgens, steroid hormones, but the amount synthesised is greater in men. However, androgens bind to certain specific receptors located in the hair follicles of the scalp. This leads to a shortening of the hair growth cycle, a miniaturisation of the follicles and a gradual reduction in hair density. The dihydrotestosterone (DHT) is a derivative of testosterone that is particularly involved in androgenetic alopecia. DHT is formed from testosterone thanks to the action of an enzyme called 5-alpha reductase.

It is noteworthy that hair loss does not occur uniformly across the scalp. Indeed, those located at the top of the forehead and the crown are most affected by baldness, while those on the sides are often protected. These latter are in fact insensitive to androgens, and are even referred to as "eternal hairs". Finally, although these hormones play a major role in baldness, other factors can cause hair loss. These include genetic susceptibility, stress, and diet, particularly a deficiency in vitamin D.

Is castor oil a solution to baldness?

Thecastor oil (INCI: Ricinus Communis (Castor) Seed Oil) is one of the most commonly used vegetable oils in cosmetics. It is derived from the cold pressing of the seeds of the common castor (Ricinus communis), a shrub mainly cultivated in China, India, and Brazil. The latter belongs to the Euphorbiaceae family. Castor oil presents itself as a thick, even viscous liquid. It is renowned for its nourishing, strengthening, and purifying virtues, and is an ally of hair, eyebrows, eyelashes and nails.

Castor oil can be used as a preventative measure against baldness. Indeed, several studies have recently explored its potential to combat alopecia and have discovered that it has an effect on hair loss. Its properties come from the ability of ricinoleic acid, an unsaturated fatty acid, to inhibit the activity of prostaglandin D2 (PGD2). This protein, in synergy with its metabolite 15-dPGJ2, interrupts hair growth by binding to the GPR44 molecular receptor. Scientists have also noticed that prostaglandin D2 is about three times more present in the bald areas of the scalp than in the hairy areas.

By inhibiting this protein, thecastor oil promotes hair growth. Furthermore, this vegetable oil helps to hydrate and strengthen the hair, and healthy hair is less likely to fall out.

How to use castor oil to delay baldness?

Apply pure castor oil directly to the scalp at least twice a week and perform massages to stimulate the hair follicle. Leave it on for at least 30 minutes before shampooing. It is indeed essential to wash your hair afterwards, as castor oil has a rather greasy texture. You can also mix it with another vegetable oil beneficial for the scalp, such as theavocado oil or the argan oil, for a lighter application.


  • FONG P. & al. In silico prediction of prostaglandin D2 synthase inhibitors from herbal constituents for the treatment of hair loss. Journal of Ethnopharmacology (2015).

  • MARWAT S. K. & al. Review - Ricinus communis - ethnomedicinal uses and pharmacological activities. Pakistan Journal of Pharmaceutical Sciences (2017).


Understand your skin
and its complex needs.

Go further: