Cannabidiol, more commonly known as CBD, is a chemical found in the cannabis plant. But since it does not contain THC, which is a psychoactive compound, it does not have any effects on cognitive functions.
What do we use it for then?
We use it topically and internally to treat pain, skin ailments and strengthen the immune system. You can read about those benefits in-depth here: CBD Oil: 7 Proven Health Benefits and Uses
Both the cosmetic and the pharmaceutical industries are aware of all these benefits and invest large sums in researching and developing them into feasible, profitable products. That includes treatment oils and ointments, as well as supplements, but sometimes even more farfetched things like CBD candles, and CBD-infused toiletries. Among all those, you can find CBD shampoos. But do you really need them, or are they a cynical attempt to cash in on our lack of knowledge?
As it turns out, there are two receptors on the scalp area that activate CBD when they come in contact with it. These CBD-infused shampoos aim to channel the anti-inflammatory nature of CBD to treat dandruff, eczema, and psoriasis. Increased blood circulation will help with oxygen flow to the scalp, culminating in healthy, nourished hair.
But when it comes to cosmetics, it's each product to its own. You can read and decipher the ingredients list on a shampoo bottle, but the ingredients are only part of the effect. It also depends on the formulation. Meaning, the amounts mixed, the quality of each component, and the consistency of the substance inside the bottle. A shampoo may advertise as anti-dandruff, and it may even work, but you wouldn't be able to tell whether this was thanks to the CBD or other beneficial ingredients in the formula.
Related: The Benefits and Uses of CBD Oil
An interesting fact worth mentioning, though, is that many manufacturers claim CBD can increase the efficacy and absorption of other ingredients, in addition to providing its own benefits. Be that as it may, still more research is required to determine the exact dosages and percentages that will truly be beneficial. In this case, the rule that says "the more, the merrier" does not apply.
Dr. Joshua Zeichner, Director of Cosmetic and Clinical Research in the Department of Dermatology at The Mount Sinai Hospital, says that if anything, the benefits of CBD will do more for the scalp than the hair itself: "CBD containing scalp products may be of benefit if you have scalp dandruff or psoriasis." Since shampoo is usually rinsed out quickly, while scalp treatments are usually leave-in, we can really see the logic in his statement. Dr. Zeichner recommends sticking to product reviews as practical advice. Look for brands you already know and trust.