While there is some debate about whether CBD derived from hemp or marijuana differs, medical observations to date are that CBD derived from either source has the same mechanism of action; however, whether CBD has more therapeutic benefits in products alone or in combination with THC and other cannabis components remains to be determined. Of note, CBD is also absent in the roots or the seeds of cannabis and hemp. While hemp seeds are a good source of protein and omega-3 fatty acids, companies that claim they derive CBD from hemp stalk, hemp seeds, or hemp seed oil are making false claims because these parts of the plants contain no CBD, no THC, and no known plant cannabinoids.
CBD binds to endocannabinoid receptor CB2, whereas THC binds to both CB1 and CB2. CB1 receptors are primarily found in the central nervous system, affecting neurotransmitters leading to CNS depression, euphoria, psychosis, impaired memory, and increased appetite and have antiemetic effects, whereas CB2 is mostly found in peripheral organs and primarily affects the immune system resulting in decreased pain and anti-inflammatory and antioxidant effects.
The skin has the highest amount and concentration of CB2 receptors in the body. As detailed in Dr. Leslie Baumann’s column “Primer on cannabis for cosmeceuticals” in Dermatology News, June 2019, skin-specific studies indicate that, when applied topically, CBD decreases sebum production and has anti-inflammatory effects. There is also evidence that CBD has antioxidant effects. Therefore, in the correct formulation, CBD may have potential in treating common sometimes debilitating skin conditions such as acne, as well as other inflammatory skin conditions.
For acne, beauty products containing CBD have the potential to help overall complexion and prevent acne scars. Because most degradation of collagen involves inflammation – whether the inflammation is secondary to excessive UV exposure, diet, poor health, or stress – the anti-inflammatory and antioxidant effects also have potential benefit in treating and preventing signs of aging. Of note, the CB2 receptor has also been shown to be upregulated in melanoma and squamous cell carcinoma. In a recent study of keratinocytes irradiated with UVA and UVB light, CBD demonstrated antioxidant activity through nuclear factor erythroid 2–related factor 2 (Nrf2) activation, as well as anti-inflammatory properties as an inhibitor of the nuclear factor NF-kappa-B. Whether topical CBD can effectively prevent or treat cutaneous tumorigenesis is promising, but large scale data are still needed.
So far, the benefits of CBD in beauty products and topical skin formulations for treatment of skin disease are based on preclinical information, and there is a corresponding lack of high-quality randomized, controlled trials that evaluate their effects on skin-specific issues. Now, with the 2018 Farm Act in place, large-scale, randomized, controlled trials with cannabinoids should be able to be performed more easily to demonstrate the dermatologic benefits of this promising compound.
Dr. Wesley and Dr. Talakoub are cocontributors to this column. Dr. Wesley practices dermatology in Beverly Hills, Calif. Dr. Talakoub is in private practice in McLean, Va. This month’s column is by Dr. Wesley. Write to them at dermnews@mdedge.com. They had no relevant disclosures.
Resources
Gallup. “14% of Americans Say They Use CBD Products.” https://news.gallup.com/poll/263147/americans-say-cbd-products.aspx.
Project CBD. “What is CBD?” www.projectcbd.org/cbd-101-what-is-cbd.
Palmieri B et al. Clin Ter. 2019 Mar-Apr;170(2):e93-e99.
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