If you want longer, healthier hair, you're not alone. Hair growth is a surprisingly common concern, and there are all kinds of products out there—from vitamins, to serums, to oils—that promise to deliver those Rapunzel-like strands.
One of the most accessible and reviewed options out there today is castor oil. This inexpensive and widely-available oil is a type of vegetable oil that's derived from castor beans, says Audrey Kunin, a board-certified dermatologist. "It is rich in ricinolenic acid, which is a nourishing, hydrating fatty acid."
And though it's surging in popularity, particularly for applications like hair growth, it's an oil that's been used for millennia for numerous topical and beauty applications, says William Gaunitz, FWTS, certified trichologist and founder of Advanced Trichology.
But is it worth picking up a bottle and applying regularly? Does it actually help stimulate hair follicles to deliver the real, tangible results you're looking for?
What to consider
- Usage: If you fall into the former category or simply want to use the oil to reap the benefits of improved scalp health and silkier, healthier-looking hair, apply the oil two to three times per week, says Gaunitz. In some severe cases, you can use castor oil daily, but should mix with 50 percent coconut oil, since the product can create sticky buildup, he adds.
- Ingredients: According to Jay Small, Co-Founder of Arey, Trichologist and Hairstylist, "I would look for products that contain other known growth ingredients and are not entirely comprised of castor oil. For those seeking natural alternatives to hair growth products, I would try products that contain rosemary oil or saw palmetto."
Does castor oil increase hair growth?
The short—and, admittedly, rather unsatisfying—answer? Maybe.
There is no evidence that castor oil applied to the scalp or hair will directly help increase hair growth, says Kunin. Rather, castor oil can indirectly assist in hair growth, says Gaunitz.
"It has many anti-inflammatory properties including high levels of omega 6 and 9s and vitamin E," he explains. Because of this, regular use—particularly alongside other proven products available through a dermatologist or trichologist can yield positive hair growth results, says Gaunitz.
But it shouldn't be relied on in every case. While castor oil can be very helpful in assisting in hair regrowth for people dealing with inflammatory hair loss, it will have very little to no impact on severe male or female pattern hair loss and nutritional hair loss, he explains.
How to apply castor oil?
It's an easy process: Simply place a couple of drops into your hand and gently massage the oil into the scalp. Let the oil sit for 45 minutes to an hour. Then, wash your hair and scalp with your preferred shampoo and conditioner.
Can you leave castor oil in your hair overnight?
Maximum benefits, please! While you can technically leave castor oil in your hair overnight, leaving any oil on overnight or for longer than four hours should only be done intermittently, says Gaunitz. "After four to six hours the oil will break down and begin to collect dead skin cells and debris leading to possible inflammation."
How long does it take castor oil to work?
Within 15 to 30 minutes of use, castor oil begins to reduce inflammation and out-of-balance microbials including fungus and bacteria, plus deliver hydrating omega fats, says Gaunitz.
When it comes to hair growth, though, you'll have to dig deep for a little more patience. "For people who will benefit, I have seen positive results typically after six to eight weeks of use," he says.
Still, it's important to note that results won't last forever. Ongoing use is required to maintain the benefits of castor oil, Gaunitz adds.
How we chose
Through speaking with multiple experts, extensive product research, and customer reviews, we were able to narrow down the castor oil market to the best products for hair growth.
The Best Castor Oil for Hair Growth
Best Overall Castor Oil
Carol's Daughter Goddess Strength Castor Hair Oil
Why We Love It
Good size for price- Designed for all hair types
What to Consider
- Some complaints of smell
Made with a seven oil blend that features castor oil and black cumin seed oil, Carol's Daughter has formulated a scalp and hair oil that moisturizes and strengthens weak strands to protect against breakage and prevent split ends. With Coco Gauff as the brand's ambassador, Carol's Daughter has been making waves in the haircare industry. Delivering seven times stronger hair and 86 percent breakage reduction, this formula is best for dry, curly, and weak hair.
Key ingredients: Helianthus Annuus (Sunflower) Seed Oil, Olea Europaea (Olive) Fruit Oil, Simmondsia Chinensis (Jojoba) Seed Oil, Cocos Nucifera (Coconut) Oil, and more
What reviewers are saying: "I searched out any hair products that would help to make your hair grow back and after careful reading of different hair products, I got the 7 oil blend and the Mimosa Hair Honey. I mixed both products together and not only has my hair came back but its even healthier and longer then it's ever been!"
Best Castor Oil on Amazon
Why We Love It
- Comes with multiple tools to apply
- Designed for eyelashes and eyebrows too
What to Consider
- Complaints of bottle top breaking
If you want castor oil that has raving reviews and speedy delivery, Amazon has an oil from Kate Blanc Cosmetics that does the trick. This castor oil is cold-pressed for maximum benefits. And in addition to the dropper, it also comes with a spoolie, so you can use the oil on your lashes or nails, too. This oil really does it all, making for a versatile product that gives you multiple ways to use it.
Key ingredients: Organic castor oil
What reviewers are saying: "So I bought this over a week ago and have been using it consistently every night before bed. I put a good amount and then massage it into my eyebrows, and I've noticed the sparse areas getting a bit thicker already."
Best Castor Oil for Curly Hair
Brigeo Curl Charisma Organic + Cold-Pressed 100% Castor Oil
Why We Love It
- Each purchase gives back
- Easy top to apply
What to Consider
- Small size for price
From one of the most beloved brands in haircare comes a wholly organic and cold-pressed castor oil to promote hair, scalp, skin, and brow health. The unique extraction process helps to retain its powerful fatty-acid and mineral-rich formula enhances dry curls and coils. Containing only castor oil, the pure formula ensures that you know exactly what you're putting on your hair and skin. Pro tip: apply to your brows or hairline with a mascara wand or cotton swab.
Key ingredients: Organic castor oil
Best Black Castor Oil
Kreyòl Essence Haitian Black Castor Oil
Why We Love It
- Dropper for easy application
- Can also be used to help fade stretch marks
What to Consider
- Complaints of the smell
Black castor oil is known to be particularly rich in all of the necessary vitamins and minerals to promote hair growth, including omega fatty acids and vitamin E. It seals in moisture to get rid of dry hair, creating optimal nourishment. This castor oil in particular is eco-conscious, made with a vegan formulation, sustainable packaging, and clean ingredients.
Key ingredients: Haitian castor seed oil
What reviewers are saying: "I had an issue with my edges thinning out. After four weeks of applying this castor oil to my edges, i've noticed thickness and fullness along the edges of my hair. I will continue to use this product and recommend it to others."
Best Expert Pick Castor Oil
Plant Therapy Rosemary & Castor Hair Oil
Why We Love It
- Smells good
- Comes with dropper for easy use
What to Consider
- Only comes in one size
This is Small's pick. He says, "When trying any product whether it be for hair growth, wrinkles or grey hair, less is more." He goes on to add, "Many products contain less of the actives you want and more of the fillers you don’t need. With so many options on the market and the time it takes for these products to show results starting with brands you can trust will be key in maintaining the consistency needed to see results." The pure and simple ingredient list makes it his pick.
Key ingredients: Prunus Amygdalus Dulcis (Sweet Almond) Oil, Ricinus Communis (Castor) Seed Oil, Rosmarinus Officinalis (Rosemary) Leaf/Stem Oil
What reviewers are saying: "I bought this because I’ve had some postpartum hair loss and I used it for only a few weeks and I’ve already noticed hair regrowth. I put it on the problem areas and leave it for a couple hours while I do stuff around the house and then I shower normally!"
Why We Love It
- Affordable
- Comes in multiple sizes
What to Consider
- Need to transfer to glass bottle as plastic can leach
The possibilities are endless with this castor oil. You can use it for your hair care, skin care, aromatherapy massage, lash growth, eyebrow strengthening, and much more. It strengthens your hair follicles by locking in moisture in the hair shafts. If using on your skin, the fatty acids penetrate your skin to retain its moisture. And if you choose to use it for muscle soreness relief, apply to tender areas for a soothing feel. It does it all.
Key ingredients: Castor oil
What reviewers are saying: "I love the way this feels and moisturizes my skin. I also use a little in my hair every night."
Why We Love It
- Vegan
- Comes with dropper for easy use
What to Consider
- Some complaints of making hair too oily
This 100 percent plant-based oil is formulated with rosemary extract and biotin to promote scalp health and hair strength from root to tip. The antioxidant blend features argan, jojoba, and of course, castor oils, to provide maximum nourishment. Designed for all hair types, this oil with help to loosen buildup. Apply it before you shampoo. The lavender scent also makes for a pleasant experience, creating a spa-like feeling as you massage it into your scalp.
Key ingredients: Rosemary extract, biotin, argan, jojoba, castor oils
What reviewers are saying: "I love the Rosemary scalp and hair oil with biotin! It smells amazing and my hair feels softer and thicker after a handful of uses."
Why We Love It
- Vegan
- Comes in multiple sizes
What to Consider
- Feels a bit thick when applying
Allpa Botanicals produces a castor oil for your hair that is deemed as pure and organic as it gets. Handpicked from tropical rainforests in the Amazon, the unique process aims to deliver the highest quality extractions in a cold-pressed and lightweight oil. Its formulation is designed to accelerate blood circulation to the scalp and fills the damaged gaps of keratin in by increasing hair shaft strength. Humectant qualities of castor oil are also said to help prevent hair from losing pigment to keep its natural color longer.
Key ingredients: Castor
What reviewers are saying: "I have been using this once a week to nourish my hair and it's so much softer! Castor oil is heavier than other oils but I love how it's really giving my hair a healthier look. Anyway as soon as you shower it all comes out pretty easily."
Brigitt Earley
Contributing Writer
Brigitt is a writer, editor and craft stylist with nearly 15 years of experience. She specializes in lifestyle topics, including home, health, parenting, beauty, style, food, entertaining, travel and weddings. She has written for Glamour, People, Good Housekeeping, Women's Health, Real Simple, Martha Stewart, Apartment Therapy, The Spruce, and more.
