There is no evidence that castor oil applied to the scalp or hair will directly help increase hair growth, says Kunin.
Massaging castor oil on the scalp boosts blood circulation to the follicles that aids hair growth, makes hair h3er and thick, and reduces hair fall. Castor oil also makes hair shiny and lustrous. Using castor oil with essential oils is also very effective.
The tl;dr: no. "Castor oil will not grow hair," says Perry Romanowski, a cosmetic chemist and the author of Beginning Cosmetic Chemistry. "There is no evidence for it and no scientific theory supporting that it would work. So yes, it's a total myth."
No, there is no evidence that using castor oil can cause hair thinning or hair loss.
A common side effect of using castor oil on hair is acute hair felting. This is a serious condition, where the hair twists and entangles and turns into hard mass like a stone that resembles a bird's nest. This condition, if started once, is hard to get rid of.
While castor oil is considered safe in small doses, larger amounts can cause abdominal cramping, nausea, vomiting, and diarrhea ( 2 , 5 ). Although it can be used to relieve occasional constipation, castor oil is not recommended as a treatment for long-term health concerns.
"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.
Castor oil is ideal for any hair type that is dry or frizzy, Kingsley says. If you have fine hair, avoid leave-in castor oil formulas, as they can be heavy on strands, she advises: "Instead, look for lightweight creams or oil-rich pre-shampoo treatments, as they won't weigh even the finest hair down." Dr.
Many hair care professionals suggest castor oil should not be used more than once a week. Castor oil is heavy, and if used often, the oil can build up on your hair and make it appear greasy.
How often can you use it: Use once per week for 20-30 minutes as a treatment. It is an oil, so a little goes a long way. Works well with: Carrier oils such as coconut (or other ingredients that impart moisture to hair). Don't use with: There are no known ingredients that negatively interfere with castor oil.
Give castor oil some time to weave its magic Ideally, you should allow castor oil to sit on your scalp and in your hair for at least for half an hour. In fact, you can even leave it on overnight, washing it the next morning. This will give the oil ample time to do its work.
Here's the hard truth: Little can be done to permanently change the diameter of individual hair strands. Thickening products can do wonders to temporarily plump hair strands, but when it comes down to it, fine hair is genetic and can't be changed.
The most common B Vitamin you might already be familiar with is Biotin—also known as Vitamin B7. If you've been looking into growth vitamins to thicken your hair, you're likely familiar with Biotin at this point. It's an essential growth ingredient often added to supplements that promote healthy hair and nails.
Here's the truth: You can't change the size of your hair follicles. If you were born with fine hair, it's genetics, and no product will completely alter that. Of course, there are ways to maintain your hair health, add volume, and keep it from getting any thinner.
Use a hair oil.
If you're to start utilizing one hair product more, let it be hair oil. Heck, you can even use some of the oil you cook with on your scalp and strands to naturally thicken it. Oils like avocado, olive, and coconut can be used as hair treatments or in DIY masks to thicken your tresses.
Leave the oil in for a minimum of 15-20 minutes. You could also leave it on overnight. You will need to shampoo multiple times to get rid of the oil. You may also condition your hair with a commercial conditioner 30 minutes before you take a shower.
Both of our hair experts recommend cold-pressed castor oil. “Cold-pressed castor oil can be used on the hair shaft. However, black castor oil should be applied only to the scalp,” explains Dr. Hill.
Castor oil is not considered very toxic, but allergic reactions are possible. Call the poison control center for treatment information.