If we believed every claim, one could argue that CBD is a cure-all for 100 percent of our beauty woes. But, as with anything engulfed by hype, that’s just simply not true, especially when it comes to hair and scalp care.

While there are some benefits to CBD and hemp in scalp and hair care, stocking your shower shelf with bottles decorated with the zeitgeist’s favorite three letters is a tad overkill. Because—here’s the thing—most hair and scalp elixirs rinse out. CBD needs time to soak in order to influence the scalp and possibly the hair, too.

“Our concern is that CBD is being infused into products of all sorts without much thought going into how CBD will interact with cannabinoid receptors and, more specific, non-endocannabinoid CBD targets at the site of application,” explains Dr. Jessica Knox of The Knox Docs, a family of physicians who specialize in Integrative Cannabinology, Functional Endocannabinology, and Cannabinoid Medicine.

“CBD works on 65 unique receptor types, all of which cause downstream effects [so] before infusing CBD into anything, a manufacturer should understand the consequences of the use of CBD at the target application site.”

Are CBD shampoo and conditioner worth it?

In the case of hair care, Dr. Rachel Knox (also of the Knox Docs) notes that “CBD likely won’t have much effect on the hair strand itself” as it’s really all about the receptors in the scalp and how that interaction might eventually impact the hair “as it grows through the scalp.” This is where CBD shampoos and conditioners come into play (or don’t).

According to Dr. Rachel Knox, the reason CBD impacts the scalp more than the strands is because “CBD has good skin penetration as a topical agent and can affect the cannabinoid receptors (CBRs) in the skin and hair follicles.” That being said, shampoo and conditioner spends only a little amount of time on our scalp—and, if you listen to the beauty pros, you should only apply conditioner from mid-lengths to the ends which means your scalp never interacts with it anyway—which “results in minimal to no CBD absorption,” says Dr. Rachel Knox.

In other words: A rinse and repeat with a CBD-infused shampoo and conditioner is more like money down the drain.

That being said, some experts believe that just coming into contact with CBD for a moment might have its benefits, making a CBD-infused shampoo and conditioner worth it on some level. “I think it’s a great idea,” says Joseph J. Morgan, MD creator of Green Flower Medical Cannabis Certification Program. “If the shampoo is formulated so that there is some topical absorption of CBD within the first two or three minutes, possible benefits will become evident.”

CBD and scalp conditions

As a known anti-inflammatory, many claim that CBD helps combat larger scalp woes such as eczema. “Studies demonstrate the anti-inflammatory potential of CBD alone, and full-spectrum cannabis oils contain other phytochemicals that have also been independently studied and found [it] potentially useful in treating inflammatory conditions,” explains Dr. Janice M. Vauhn-Knox.

“Eczema, however, is an external expression of internal inflammation [so] topical CBD would not treat eczema at the root cause.” Instead of searching for a CBD scalp treatment to combat eczema topically all on its own, try incorporating internal products like tinctures, or consuming a natural, whole food diet. Dr. David Knox suggests putting “emphasis on consuming high quality saturated fats, like those from hemp seed oil” as well as eliminating inflammatory foods such as processed foods and sugar.

In addition to scalp conditions, many experience seasonal dryness—aka itchiness—of the scalp which, might actually be soothed by a CBD product, though Dr. Jessica Knox believes that a portion of that relief would come from the nourishment of the carrier oil, not just the CBD itself. However, “itchiness is modulated through non-CBR receptors called TRP receptors, representing just a few of the 65 receptors CBD is known to bind to,” so it definitely wouldn’t hurt to give it a try. Morgan agrees, noting that the psychological effect is also beneficial as “the user thinks CBD will be effective and, by thinking positively, the scalp becomes less itchy.”

Why CBD doesn’t actually “strengthen” hair

It’s true that CBD oil often contains hair-strengthening vitamins such as vitamins A, C, and E which are all antioxidants that can benefit the hair’s keratin (aka, the structural protein that makes hair strands long and strong). However, CBD on its own doesn’t actually have these properties. In fact, there are no vitamins in CBD as it’s “a single molecule itself,” says Dr. Janice M. Vauhn-Knox.

Again, it’s the carrier oil found in CBD oil—which is often derived from plant-based fats such as olive oil, hemp oil, and coconut oil—that features such vitamins. That means when it comes to CBD you might find you’re better off spending your money on a plant-based shampoo than a CBD shampoo per se.

CBD vs. hair growth (and loss)

Hair growth is huge in the hair care industry—not only from a vanity perspective but a hair loss perspective, as 80 million people in the US alone experience hair loss. CBD is entering hair growth conversations around whether or not it can benefit growth efforts. As it turns out, it’s a very fine line. CBD may encourage hair growth but also hair loss.

“According to an article from the Journal of Investigative Dermatology in July 2019, very low CBD dosage will help to grow human hair,” says Morgan. However, “high concentrations of CBD may cause hair loss.” The reason it can go both ways “has to do with the complex properties of CBD.”

To dive deeper into this, Dr. Rachel Knox explains “activation of CB1 receptors in the hair follicles may contribute to decreased hair growth,” noting that “CBD can increase the CB1 activators and anandamide (AEA) by blocking FAAH, the principle degradative (or breakdown) enzyme of AEA.” Unfortunately, when AEA’s presence is increased it also means increased activation of the CB1 receptors “in a dose-dependent fashion.”

All of which is to say, it depends on the root cause of the hair loss to begin with. So don’t panic just yet.

When wondering whether or not CBD can improve hair growth, the question does not have a simple yes or no answer. “The ‘just add CBD’ approach … is not as simple as people think and might cause some major unintended downstream problems for consumers,” says Dr. David Knox. “This is why making products with purpose that are held to high-quality standards matters.”

Whether it be hair growth or a soothed scalp, there are many unknowns about CBD’s effect on hair and scalp health at this point. While there are some smaller studies out there—and other studies that might help experts theorize better—the bottom line is that more research is needed in order to properly determine whether CBD hair products “work” or not.

By Jessie Quinn

October 16, 2019

Jessie Quinn is a Los Angeles-based writer with work published in NYLON Magazine, Brit + Co, Girlboss, and more.