Castor oil is a vegetable oil made from Ricinus communis castor beans. Anecdotal claims suggest that it has benefits for hair health.
Castor oil is a highly versatile oil used in cooking, pharmaceutical products, hair care and skin care products, and industrial lubricants. The oil, which stems from pressing castor beans, is colorless and has a mild scent.
This oil has been used for centuries, and many people tout it as a natural remedy for various ailments. However, research on its benefits for hair has limits and is mainly anecdotal.
There is mixed evidence for the benefits of castor oil for hair. One 2022 research review looking at the benefits of oils such as coconut, castor, and argan oil for hair found weak evidence that castor oil may improve hair growth or quality.
A 2023 review cites an older 2008 study that found that a lotion containing 35% castor oil increased the length, thickness, and softness of rabbit hair without any negative effects. However, further research on human hair is necessary.
Certain oils can benefit the hair in various ways because they increase moisture and strengthen the hair to help prevent breakage and dryness.
In addition to the hair on the head, castor oil may benefit hair on other areas of the body, such as the eyebrows and eyelashes.
What is castor oil?
Castor oil is a vegetable oil made from the pressed seeds of the Ricinus communis plant.
Ricin poison is made from the waste material from leftover processed castor beans and is toxic to cells. According to the
Castor oil is a colorless, mildly scented liquid. Its use for possible hair growth benefits may date back to ancient Egypt. The castor oil production process removes any traces of ricin.
The chemical composition of castor oil includes:
- ricinoleic acid
- dihydroxy-stearic acid
- stearic acid
- eicosanoic acid
- linolenic acid
- palmitic acid
Anecdotal evidence and some studies suggest that castor oil has benefits for hair, including:
- being moisturizing, particularly as a result of its high ricinoleic acid content
- being nourishing due to its high content of fatty acids, such as linolenic acid
- having good penetrability, which allows quality nutrients to reach the hair follicles
- being antifungal and antimicrobial
- stimulating prostaglandin D2 synthase to promote hair growth
The main risks of using castor oil may include:
- skin irritation
- hair matting as a result of using too much oil
- clogged pores
It is always best to conduct a patch test before using a new product on the hair or skin.
A person can massage a small amount of castor oil onto the scalp for a few minutes, either on its own or in combination with a lighter oil such as coconut oil. There are no specific guidelines for use, but anecdotal evidence suggests that a person can leave the oil on for more than 10 minutes or leave it on overnight before washing it out.
Conduct a patch test to check for any possible allergic reactions.
A person can take the following steps when using the oil on the eyelashes or eyebrows:
- Use a clean cotton swab to soak up a small amount of castor oil.
- After cleansing the face, run the cotton swab over the eyebrows and eyelashes lightly to coat the hair in oil, being extra careful not to get any oil in the eyes.
- Leave it on overnight or wash it off after a few hours as part of the usual cleansing routine.
Castor oil is a highly versatile vegetable oil made from the beans from the Ricinus communis plant. According to anecdotal evidence, its possible benefits for hair include moisturizing, nourishing, and promoting hair growth. However, further research is necessary.
Before using castor oil, it is important to conduct a patch test to check for any allergic reactions on the skin.