Castor Oil for Eyebrows: How to Use for Brow Growth

There's a reason why eyebrows are such a hot topic– and why people who participated in the skinny brow trend in the '90s are traumatized. The shape of your brows can help to open up the eyes, give structure to the face, and tie your entire makeup look together. So it's no shock to us that when a magic ingredient comes along, promising to help them grow thicker and faster, people are all ears.

So, does castor oil have what it takes to transform your arches? When you Google "castor oil to grow eyebrows," you'll likely find mixed reviews. Some people rave about the hair-growing benefits of the fatty-rich oil, while others scoff at the claims. But which camp is in the right? We spoke with board-certified dermatologists and brow experts to find out the truth. Read on to learn more about castor oil for eyebrows.

What Is Castor Oil?

"Castor oil is a vegetable oil pressed from castor beans," says trichologist Gretchen Friese. Brow expert Sabah Feroz adds: "Castor oil is filled with vitamins that our hair and skin need to support itself. It is high in omega-6 fatty acids, vitamin E, and many other beneficial minerals that moisturize and support healthy hair growth."

Purported Benefits For Brows

When asked about the benefits of castor oil, Jamé Heskett, holistic doctor and author of The Well Path, once told us the following: it improves circulation; stimulates the lymphatic system; works to kill fungi, inflammation, and dermatitis; heals acne and injuries by reducing the bacteria and healing wounds; reduces cellulite and acts as a powerful emollient. Not a single one mentions anything to do with hair growth. But some people swear by the stuff for getting bold, bushy brows or long, luscious lashes.

So, what's the truth? Friese says castor oil "has been used for years to treat various conditions, including hair loss. While there haven't been scientific studies that prove that castor oil can regrow hair, it's a low-risk remedy that may help you get thicker/fuller eyebrows." dermatologist, Hadley King, MD, echoes this: "Castor oil is not damaging to the hair and can provide some conditioning that improves the flexibility of the hair fiber," she says.

In short, there's a lack of scientific research about the topic, but there may be anecdotal evidence that suggests castor oil works for hair growth.

Does Castor Oil Work For Brow Growth?

"Currently there is no real evidence that castor oil affects eyebrow growth," says Friese. "However, there is evidence that ricinoleic acid, which is a chemical compound that makes up [the majority] of castor oil, may treat hair loss."

Dr. King expounded upon this: "The thinking is that the ricinoleic acid in castor oil activates a prostanoid receptor and has been shown to increase [the] synthesis of prostaglandin e2 in some tissues in vitro, and we know that prostaglandin analogs can be helpful for hair growth (Latisse), so this could be a possible mechanism of action," she explains. "But there is no scientific evidence showing that castor oil stimulates hair growth." Dr. King also explains that castor oil has been shown in a study to increase hair luster, but there are no studies that show that castor oil directly causes hair growth. "There are plenty of anecdotal stories, but there is no scientific evidence."

Brow expert, Jordan Feise– not to be confused with Gretchen Friese, also in this story– adds that castor oil isn't going to cause major growth. "It nourishes the brows and helps keep them moisturized, but I wouldn't expect it to transform your brows overnight," she says. "Think of it more as good maintenance for your brows. It helps keep the brows conditioned, which could lead to growth and keep your brows healthy, but it's not a miracle growth serum. I think it's all about setting expectations here."

How to Apply Castor Oil to Brows

Castor oil can be used daily, according to Friese. It might be a good idea to perform a patch test if you've never used the ingredient before to ensure you don't react. Also, only pure castor oil should be used for this purpose.

"Make sure your eyebrows are clean and free of makeup. Use a cotton swab or clean mascara wand to wipe a small amount of castor oil over the eyebrows and massage the oil into the eyebrows. Avoid contact with eyes," recommends Friese.

If you're looking to use castor oil for hair growth, Feise says to avoid putting your skincare on your brows. "This happens all too often as we lather on our skincare routines, but if you can remember to steer clear of the brows, they will thank you with more growth," she says. "In particular, try to avoid any actives (think AHAs or BHAs), retinol, alcohol-based products, and anything with fragrance on the brows." 

Alternatives to Castor Oil for Brow Growth

We asked Dr. King to share a few alternatives for cultivating more robust brow hair.

• Latisse: "The gold standard for lashes remains Latisse, and it is safe and effective for eyebrows as well," says Dr. King. "Its active ingredient is bimatoprost, a prostaglandin analog, which has been shown in clinical studies to make eyelashes grow longer, thicker, and darker. It works by lengthening the time the follicle stays in the growth phase." In some people, Latisse can cause irritation or a change in eye color. Additionally, "Latisse is pregnancy category C, meaning that it has caused adverse effects in animal studies but has not been tested in humans."
• Rogaine: "Another option would be Rogaine (minoxidil): One study looked at the efficacy of minoxidil three percent for eyebrows and compared it to Latisse in a 0.03 percent concentration," says Dr. King. "After 16 weeks, about 50 percent of participants saw hair regeneration nearly equally with both products. Based on this one study, Rogaine appears to modestly increase eyebrow growth and is comparable to Latisse. "Researchers also concluded Rogaine was safe and effective for eyebrows in a placebo study. That said, it does come with potential downsides. Along with irritation, "side effects from applying Rogaine to the eyebrow area include burning, dryness, itchiness, redness, and scaling," she notes. "It's also possible to inadvertently get the product on other parts of your face, [resulting] in increased hair growth in these areas, which may not be desirable."
• Over-the-counter products: "[Several] OTC cosmetic products are advertised to increase the length, fullness, and/or darkness of eyelashes and brows," says Dr. King. "These products contain various ingredients such as 'proprietary peptides,' natural extracts, vitamins, and prostaglandin analogs. As cosmetics, the efficacy of these OTC products has not been critically evaluated, and their safety has not been fully studied. Most are applied to the skin of the upper eyelid margin, and the mechanisms by which they may affect eyelash growth are largely unknown and unproven. These products also vary in the quality and comprehensiveness of patient/consumer education regarding proper use."

The Final Takeaway

"Castor oil can be a safe and affordable and natural home remedy," says Friese. It may not be a miracle cure for over-plucked or naturally thin brows, but at the very least, it is moisturizing—and hey, maybe nightly application will beef up your brows. As with any new skincare regimen, start slow and monitor how your body reacts. When in doubt, check with a dermatologist before using, and discontinue immediately if you experience irritation, hair loss, or discomfort.