May 20, 2020 at 07:22PM
Every so often, a beauty treatment or claim sets social media and the internet into a tizzy: Castor oil is certainly one of those ingredients that garners significant fanfare, as well as detractors. The classic oil is thought to be the golden elixir of hair growth, but most professionals and the research says, ehh, not really.
So what’s the truth about castor oil? Should you even be using it? Our investigation.
What is castor oil?
This endlessly popular oil has been a beauty stable for many, many years. “Castor oil is one of the oldest forms of medicines worldwide, especially in India, where it’s widely available and used in ayurvedic medicine,” writes Bindiya Gandhi, M.D., of castor oil’s many health benefits.
It is a vegetable oil pressed from castor beans and is especially high in ricinoleic acid (around 85 to 95% content), as well as oleic acid and linoleic acid. It’s also rich in vitamin E, unsaturated fatty acids including omega-6 and omega-9 fatty acids, minerals, and other antioxidants. Thanks to these properties, “castor oil has documented anti-inflammatory, anti-allergenic, antioxidant, antifungal, antimicrobial, immune-boosting, and analgesic properties,” Gandhi says.
It’s a medium-weight, odorless oil that acts as both an emollient and an occlusive. (Emollients are essentially conditioners, while occlusives act as a seal.) Its emollient properties help it penetrate strands and the scalp to hydrate, imparting nutrients and softening agents. The occlusive nature wraps around the strand providing a coating to keep moisture in as well as protecting the strand from physical damage and environmental aggressors.
Does castor oil cause hair growth?
Here’s what board-certified dermatologist Whitney Bowe, M.D., had to say: “There’s no published data showing that castor oil can help, but I do have the occasional patient who swears by it.” And that’s basically the best answer you are going to get. There are just no studies, research papers, or published resources to suggest that castor oil is actually helping hair grow faster or spurring regrowth—and, yet, anecdotal evidence abounds.
So research says that it’s not actually growing or regrowing your hair—but is it doing anything? Well, the answer to that question is a resounding yes.
Benefits of castor oil for hair.
Maybe it’s not aiding in growing your long locks, but it’s still a highly beneficial oil. Like your skin and body, your hair and scalp need antioxidants, fatty acids, and minerals for optimal health, hydration, and shine. This oil, like we’ve noted, is chock-full of them.
Antioxidants (like vitamin E) have been shown to fight free radicals in hair as well as minimizing inflammation at the scalp. Free radical damage has been linked to graying and aging of the hair. Inflammation has been linked to flaking, dryness, redness, tenderness, and even alarmingly, hair loss. So maybe castor oil isn’t helping your hair grow, but it is likely helping you keep the hair you have. The fatty acid content provides moisture to both the strand and skin, and research has drawn a connection to staving off hair loss as well. (So, again, this is not helping your hair grow but is perhaps preventing thinning in the future.)
How do you use it?
The same way you use any natural hair oil! Here, our favorite uses:
- As a pre-shower treatment. One of the best natural deep treatments is a pre-shampoo mask. And it’s so easy: Simply coat your hair with the oil, let it sit for 10 to 30 minutes (you can pull it back into a bun or pop a shower cap up top it so you don’t make a mess), and then rinse as usual. If you have really dry hair and scalp, you should apply it root to tip; if you tend to have an oilier scalp, just do midshaft to the end.
- For a scalp massage. This use may actually stimulate hair growth. In one study, doing regular scalp massage was shown to improve hair growth as it encourages blood flow to the hair follicle. As with any kind of massage, it’s best to use an oil while you do it: Simply wet the pads of your fingers with a few drops of the oil and follow our self-massage guide here.
- Post-wash leave-in conditioner. Natural oils make for great leave-ins post-wash, as they are able to help coat the cuticle and trap in moisture. And since they are all-natural, they are free of silicones (read all about why you may want to skip silicones here).
- Dry end mender. You can’t fix split ends, you can only snip them off (try dusting for a great at-home technique). However, you can improve their appearance by adding shine and conditioning agents to dry ends. This won’t seal splits back together, but it will temporarily make them look frayed.
- Fly away smoother and styler. Or say you are going for a sleek, pulled-back style. You can easily smooth in castor oil to help lay down flyaways and add shine.
If you really want to encourage hair growth, read our best tips here. And then feel free to still use castor oil—it’s a great oil!—just know it’s likely not stimulating growth. However, it has a host of other benefits to look forward to.