Update 2/28/20. Can castor oil help your hair grow? That's the question people started wondering about as they were reading the Viviscal review. People were asking if castor oil, could re-grow hair or make it thicker? Some people said it was actually working for them. After a quick search, I discovered, sure enough, lots of websites discussing this hair treatment. But, is there any proof for it? And by proof, I mean clinical evidence. In this review, you'll learn about the research on castor oil and hair growth. Does it really grow hair, regrow it or make hair thicker? Let's see what we can discover. Also, see the review of Viviscal for more information.
Other Hair Supplement Reviews
See these additional reviews for more insights:
- Viviscal Review
- Nutrafol vs. Viviscal Review
- My Biotin Pro Clinical Review
- Amplexin Review
- Amla Fruit (Indian Gooseberry) Review
- Halo Beauty Review
- Creatine and Hair Loss Review
- PHYTO Re30 Review
- Rosemary Oil For Balding and Regrowing Hair (video)
- Can Lavender Oil Regrow Hair? The Proof (video)
- Can Peppermint Oil Regrow Hair? The Proof (video)
What Is Castor Oil?
Castor oil is the oil that comes from the castor bean. The scientific name for the castor bean is Ricinus communis. While the oil has been used to treat many things over the years, for those who are old enough (I'm not one of them), some may remember it used as a laxative and/or punishment used by parents on misbehaving kids.
How Is It Supposed To Work?
While I could not find anything definitive on how it is said to regrow hair, some websites say castor oil works by improving circulation to the follicles on the scalp. The oil does contain many substances such as vitamins and fatty acids which various websites tout as helping hair growth. Few websites show evidence of it.
Another theory involves inhibiting a hormone-like compound called prostaglandin D2 (PGD2). Some research finds that the scalps of bald men show higher levels of PGD2 than men who are not balding. One of the ingredients in the oil is called ricinoleic acid (rey-sin-ole-ick acid).
At least one study has noted that ricinoleic acid can inhibit PGD2. In theory, this might mean more hair growth. Currently, human research involving ricinoleic acid and hair growth appears to be lacking. See this review of PGD2 and hair loss, for more information.
Castor Oil Hair Growth Research
I have seen before and after pictures on the internet. Some of the pictures are impressive. But, the real proof for whether the oil is going to work is to see if there are any clinical studies done on people – not test tubes studies and not lab animal studies.
Searching clinical databases for these search terms:
- Castor oil hair
- Castor oil baldness
- Ricinus communis hair
- Ricinus communis baldness
- Castor oil PGD2
- Ricinus communis PGD2
Did not reveal any human proof. Likewise, various websites stating it worked did not reveal any proof either. In addition, no evidence could be located on whether blocking PGD2 in people leads to hair growth or a slowing of hair loss either.
One study has noted castor oil improved the luster of hair. In other words, when light hits the hair, it looks better. Might this “optical illusion” effect play a role in the perception of some that they are growing new hair? Might it be possible that what people are seeing as “new hair” is just the oil sticking to existing hair, making it look thicker? I'm speculating of course. I have not idea either way.
Lack of evidence does not mean something does not work. It might be that interest in castor oil helping hair loss is in its infancy. I will update this review as I become aware of new research.
What About Eyebrows?
Several websites extol the benefits of the oil for helping regrow eyebrows and eyelashes or make them thicker/fuller. Maybe it does or maybe it doesn't. No clinical studies on eyebrows and the oil could be located. Be careful with castor oil shampoos getting in your eyes.
Do You Drink It?
Every website I saw on this issue recommended placing castor oil on the hair. Do not drink the oil to help your hair grow. Remember, castor oil is a laxative. Every website looked at said the same thing: castor oil is said to work when a small amount is massaged into the scalp and left on for a period of time before washing it out.
Where Do You Buy It?
You can purchase castor oil at any health-food store. I have seen it in GNC and Vitamin Shoppe for example.
How Long Does It Take To Work?
Some recommend using the oil a couple of times a week and leaving it on the scalp for a few hours before washing it out. From what I saw, if it is going to work, it might take several months of regular use before noticing any hair growth.
What Type Is Best?
There is no proof one brand is better than another. That also goes for brands that are cold-pressed, organic, etc. There's not enough evidence yet. Until proper human studies are done, you have two options:
1. Use the brand that people you know and trust have used.
2. Start with the least expensive brand first and see if that works.
Fortunately, most brands of castor oil is not expensive.
Here it is on Amazon if you want to compare prices.
Castor Oil Shampoo
Castor oil shampoos might be an option for those who don't want to mess around with using the oil on their hair. Keep in mind shampoos may contain many other ingredients too. Whether these other ingredients add anything to the “hair-growing effects” is not known.
If you're looking for the shampoo with the most castor oil, remember ingredients listed at the top of the ingredients list are the most abundant. The further down in the ingredients, you see it listed means less oil is present.
Here's castor oil shampoo on Amazon
Is Castor Oil + Coconut Oil Better?
It's unknown. Studies comparing these oils to each other could not be located.
Castor Oil Side Effects
Massaging the oil into the scalp would probably have few side effects in most people. Other than it may be smelling bad, it appears to be safe. Here are a few things to consider when using castor oil.
- In one report, doctors noted a “contact allergy” when it was placed on the skin. Others have also noted allergies to castor oil too.
- I don't know how common castor oil allergies are, so just in case, it may be wise to rub a small amount onto the skin for a few days to see if you personally have any negative reactions to it.
Some may have heard that the castor bean is the source of ricin, a deadly poison. While this is true, there is no ricin in castor oil.
If anyone has any thoughts or tips on how to use castor oil best, leave a comment below.
Does Castor Oil Work?
Given that several people have told me it was helping their hair growth, I was disappointed to see no human clinical evidence to confirm or deny this. Is this because you can't patent castor oil? Maybe. Either way, it will take human clinical research to know for sure. The good news for those who want to try this is the oil isn't expensive.
I rub a drop of castor oil on my eyelashes every evening before going to sleep, and when I saw a pic of myself in profile, I was surprised at how long my lashes were. Seems to work. Never tried it on my scalp, though.
Ann thanks for the feedback. I’m glad to hear castor oil has worked well for you. If you ever try it on the scalp, let us know what happens.
Hi, Thank you for this post, but hair growth or new hairs regrowth is not the same, what about just hair growing faster?
Hi Vika, you are welcome and uou are correct – growing new hair and hair growth are not the same thing.
I can tell you B vitamins such as biotin can help hair – and nails – grow faster. That’ hair supplement almost always contain biotin. I have not seen anything about castor oil helping hair grow faster but it can’t hurt to try.
Have you tried castor oil for growing hair faster – or regrowing hair? What happened?
Thank you for this post. I was looking for good evidenced based information. And, this post is the best I’ve found even if the result is that there none. The anecdotes posted in response are interesting though.
Hi Gayle, thanks for the compliment. I’m happy you took value from my review. Have a great Holiday! 🙂
Your article was exactly what I was looking for. I googled research on castor oil and hair growth. I wonder if there could be a people’s research group of some kind where people participated voluntarily to figure some of these things out. I know it would be anecdotal, and I know it would not be scientific. And I have a heart grown in science.
But the studies are becoming more and more contaminated with economic motives. Same problem with individuals doing studies. I am old, and I have watched the health and supplement movement develop since the early 60’s. I grew up on fads in health care. I tried lots of different things. I have been able to be healthier than a lot of people around me (not scientifically proven). My friends are constantly looking for the next silver bullet. I don’t think there is one. I am trying no supplements, no added this or that.
My friends are now doing castor oil. I am using it right now as a cosmetic. I don’t use any other cosmetics and haven’t for decades. I just don’t like everyone getting all excited about the next greatest thing and throwing all their energies into that, then running off to the next thing, accumulating bottles and vials of things not proven spectacular.
Underlying all this is either a dissatisfaction with either health or looks, trying desperately to find a way to avoid just taking regular good care of yourself. You probably know what is good for you and what is not, and want to find ways to justify keeping on with bad lifestyle choices.
I certainly know that I do not do everything I could, the body is amazingly forgiving until it breaks down. I live with my own rationalizations. I don’t want to be swept away in the next wave of hope and commercialism.
Hi Lucy, so glad you found my review useful. Feel free to share it with your friends. I’ve also noticed castor oil – and other things – being touted for economic gain by people trying to make a quick dollar. Whether or not they are proven correct with castor oil, only time will tell. You are right about the body being very forgiving. It sounds like you are doing all you can do to stay healthy, which at the end of the day is the best medicine.
FYI science on same topic: https://www.naturallycurly.com/curlreading/ingredients/can-biotin-castor-oil-really-thicken-hair/
Hi Amy, thanks for the link. It looks like the Sister Scientist also found little evidence for castor oil thickening hair.
What do actually know?
Nonsense article.
Riya, how is summarizing the research -or lack of it in this case – constitute a nonsense article? Don’t just make anonymous attacks from the cheap-seats; how about some better feedback on what you want to see me cover?
Nonsense comment, more like.
This is a well-researched article that answers the question ‘Have there been any clinical studies on the effects of castor oil on hair growth?” – just because the answer is “Not that I could find”, it doesn’t mean the article was nonsense.
Dot, thank you for saying that. That’s exactly what I was trying to accomplish. 🙂
I too use Castor Oil and combine with either Jojoba or Argon oil. Just put in a small dropper bottle and shake to mix then apply to wet hair, leave on for a few hours, and rinse off using a beaten egg.
Thus far, while I haven’t noticed hair growth per-say, I have noticed my hair is much healthier, softer, and shinier since beginning to use it 6wks ago, once a week. It is a staple in my beauty routine now just because of how amazing my hair feels after!
And my split-ends are significantly minimized (I have think coarse hair and had them in abundance!). It does seem somewhat longer, but I don’t know if it’s from the oil or just normal growth. Hope this helps!
Hi Melissa thanks for sharing and it does help. The egg trick is something I’m sure a lot of people will be trying 🙂
I too use Castor Oil in my trouble spots and it works like a charm. I am black so I have kinky hair and we usually just grease our scalp and leave it on. I dont even need a carrier oil. Also castor oil is a good curl enhancer. I put the oil on my wet hair and then twist it and it it out the next day. The curls are defined and shiny (its a little bit greasy tho).
Sometimes my hair will grow too thick and Ill actually have to reduce my castor oil use.
I also use it on my face as a cleanser using the oil cleansing method. When I do that my eyebrows grow super thick and fast.
I have used castor oil for hair growth and i do recommend it for everyone. We arabs tend to take good care of our hair, and a full head of long silky hair is considered very attractive, so we usually grow up with our mothers passing on the secret for healthy hair, which is oil in general, usually olive or castor oil.
However, i personally never cared about my hair nor my mother was about the whole passing on traditions thing. I started balding at the age of 14 and when i became 20 my scalp was very much noticeable with no effort made. I can tell you that i have tried every pill and every product that promised me good results and i did get results, however they’d be lost as soon as i quit.
When my grandmother heard of my dilemma she quickly advised me with using castor oil (my friends always advised me the same but i would never listen to anyone). I was so hopeless that i thought of giving it a try finally and i am so glad that i did. I have been using it for 5 weeks and I have already seen remarkable results.
I do advise you to take it up, any castor oil do the job (black, organic… bullshit), personally i put 2tbsps of olive oil for every tbsp of castor oil in a bottle and shake it well before using. I do it once a week. I took pictures every week of my progress so i can see it for myself. Good luck 🙂
Hi Hind, thank you for sharing your experiences and hair growth recipe. I’m happy that castor oil and olive oil are helping your hair growth.
Hi, wil you please post your hair growth progress photos here on this site?
I read a lot about beauty items, remedies, DIY skincare. It seems that the trend for using castor oil to regrow hair is to use Jamaican Black Castor Oil. Simply apply a small layer on areas of concern and massage in well. This supposedly works on the eyebrow area, too. Apply at bedtime every night and be patient.
*Make sure to put something over your pillowcase to avoid staining.
DIY’R, Ive seen websites talk about the benefits of Jamaican Black Castor oil. What I never any of them show me though, was studies that it actually worked. That doesn’t necessarily mean it doesn’t work but rather I cant find any studies to confirm/deny it. Hoping someone will chime in with some evidence one way or the other.
Hey Joe, for me the Jamaican black castor oil seemed to work better for my eyelash and eyebrows. I don’t know if there are any actual studies relating to it but it worked pretty good from my personal experience.
Hi Christina, thanks, I’m glad the Jamaican black castor oil worked for your eyelashes. Did you have any eye burning with it?
I don’t recall it burning granted It didn’t get in my eyes. But I mixed it with extra-virgin coconut oil so maybe that soothed. Most of the times when I use it, it’s right before going to bed soo… Maybe that’s also another reason?
Thanks Christina, I’m always curious about stuff we put close to our eyes. Glad to here there was no problems 🙂
I am using dabur castor oil. .does it work in same way?
Hey Joe, I’ve been using castor oil with a little lavender essential oil on 2 thin spots around my temples. The spots have gotten thicker and the blend has also helped with a dry, flaky scalp.
Crystal, thanks for the feedback. I really wish some researcher would take a good look at castor oil for hair growth. Given the people who have recently been telling me about it, I think its worth some research to get to the bottom of it. I’m glad it is helping you.
Quick question, I’m finding this fascinating. Do you apply it straight/directly on a dry scalp? Or should the scalp be dampened a little bit…. then leave in for a while and then washed out?
Thank you
Hi Julie, while I dont think it matters, I would dampen the hair first and leave it on for a little bit. If it works, I do think it will take time. If you try it, let me know what happens.