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Castor oil has experienced a surge in popularity over the last few years, thanks to the increasing interest and demand for natural products and remedies. Purported castor oil hair benefits particularly fascinate people. In this article, we will examine these popularly touted castor oil hair benefits to help you decide whether to try castor oil as well.
I first started using castor oil about three years ago, when I noticed (to my horror) that my hairline was thinning around my forehead. After hearing about castor oil’s ability to promote hair regrowth, I bought a bottle and applied castor oil to my scalp one to two times a week.
Over time, much to my delight, my hairline filled back in. I honestly have no way to quantify whether castor oil was solely or primarily to thank for my hair regrowth, but I believe it contributed to some degree. Thus, my impression of castor oil is positive enough to recommend it to others who are seeking answers with their hair.
If you have read any of our other articles, you have probably gleaned that we love to quote science and studies as much as possible to help you make informed decisions regarding your health and lifestyle. So, even though studies are somewhat lacking here, we will still attempt to discuss castor oil hair benefits in a similar fashion in this article.
What Is Castor Oil?
Castor oil is derived from castor beans off of the castor bean plant (Ricinus communis), which is interestingly related to the classic Christmas plant, the poinsettia. Castor bean blossoms exude a similarly bright red color and are thought to originate from Africa, where ancient Egyptians purportedly used castor oil in their hair, among other uses.
If you saw the scientific name for castor beans, Ricinus communis, you might notice it contains the word, “ricin.” Yes, this is the same ricin that the U.S. government identifies as a poison, and which has been used at various points in history. However, fear not: although ricin is obtained from mashed up castor beans, castor oil does not contain ricin.
Like all oils, processors can extract the oil either through cold pressing or the use of heat. Cold-pressed castor oil does not use heat to facilitate oil extraction, or incorporates cold water to moderate the temperature. Like with many other types of oils, most advocates view cold-pressed oil as superior, because the lack of heat preserves more nutrients in the oil.
Thus, if you buy castor oil, you should select one that says “cold-pressed” just to be safe.
How to Use Castor Oil for Your Hair
Some guides suggest mixing castor oil with lighter oils, like coconut or olive oil, to enhance your ability to spread the oil throughout your scalp. By itself, castor oil is quite thick and sticky, so spreading it undiluted onto your scalp can prove tedious, depending on your hair length and texture.
Personally, I’ve always put straight, undiluted castor oil on my scalp. However, my focus was my hairline along my forehead, so I didn’t have to weed through a lot of hair to get the oil on my skin in these areas. I was less concerned with thorough distribution along the rest of my scalp, but if you are concerned about thorough distribution, you may want to mix castor oil with another oil to facilitate even distribution.
Some people choose to leave castor oil on their hair overnight, but I always washed it out the same day, because I didn’t want to deal with sleeping with a thick oil in my hair or wearing a hair cap at night.
My routine was to apply castor oil a few hours before washing my hair the one to times a week that I would wash my hair. That way, the oil would have some time to work any magic, but I could also wash it out before bed. Because I only put castor oil on my scalp and not all down my hair, it was easy for me to wash out.
Some advocates put castor oil throughout their hair to try to improve hair health and luster. If you choose to do this, then just keep in mind that washing all the oil out may require extra effort, like a second shampooing. Otherwise, washing castor oil out of my scalp only required regular shampooing (even with mild, “natural” shampoo).
The Science on Castor Oil Hair Benefits
Firstly, I must admit that studies are severely lacking on castor oil hair benefits. I found one study on castor oil’s effects on hair regrowth. This study determined that in individuals with central centrifugal cicatricial alopecia (i.e. a condition of unknown causes, where destruction of hair follicles and scalp scarring leads to permanent hair loss), castor oil failed to regrow participants’ hair.
However, I found no study on castor oil’s effectiveness in individuals without central centrifugal cicatricial alopecia, i.e. on individuals with normal, healthy scalps. Also, that same study determined peppermint oil had no effect, even though a prior study determined peppermint oil resulted in increase hair growth in mice subjects.
Thus, we can’t accurately conclude whether castor oil or any other substance is effective for hair growth in individuals that don’t have a documented condition like alopecia. Like with any substance or remedy, different individuals may react differently.
The only other publicly available study regarding castor oil and hair health is a study that documented castor oil’s ability to improve hair luster. So, you can use castor oil if you want shinier, more lustrous hair.
Castor oil also has documented antimicrobial and antifungal properties, so can help combat any infection on your scalp, thereby improving scalp and hair health.
(As a side note: you can use castor oil on skin rashes and inflammation on other parts of your body as well.)
Overall Science on Castor Oil Benefits
As you can see, studies are generally lacking on castor oil hair benefits, particularly regarding stimulating hair growth or regrowth. However, studies do support castor oil’s ability to boost hair luster and improve scalp health, where the latter can translate to better hair health.
Yet, despite the lack of scientific studies on castor oil’s ability to promote hair growth, a lot of anecdotal evidence exists, as we will discuss below.
Anecdotal Evidence of Castor Oil Hair Benefits
Scientific studies are lacking on castor oil hair benefits, but anecdotal evidence is not.
I shared my positive impression of castor oil earlier. Although I don’t recall exactly how soon my hairline grew back in after using castor oil, pictures suggest my previously thinning hairline was no longer detectable (as in zero lingering signs!) after about seven months.
I also recall my hairdresser noticing little “baby” hairs coming out of my head a few months after using castor oil. She concluded these hairs were definitely new growth, which encouraged me to keep using castor oil at the time.
Three years later, I still use castor oil weekly, since I see no harm in its continued use. Even though my hairline is no longer an issue, I openly welcome any additional hair growth or thickening, especially since apply castor oil requires very minimal effort!
If you look on the Internet, you will find countless blogs and accounts of people crediting castor oil for thickening their hair, eyebrows, and eyelashes! (I have not tried castor oil on my eyelashes or eyebrows, but may tinker with the latter and will report back if I do!)
If you look at reviews for the castor oil that I use, you will see similar accounts. Either you can believe them or not, but unless you suffer negative side effects (see next section), then you might as well give castor oil a shot!
Precautions on Castor Oil
Like with any substance, some people can be allergic to castor oil, so you should always test a small spot first before liberally applying the oil. The favorite test spot for most hair or cosmetic product guides is the inside of your elbow.
Please share your thoughts on castor oil hair benefits below, particularly if you’ve tried castor oil before. Curious minds want to know!