CBD say what? The role of CBD in cancer care

Written by Kaitlyn Shang, NYU, Class of 2026

CBD, or cannabidiol, is sold everywhere from grocery stores to farmers markets to main street shops. According to Statista.com, the US reached $1.918 billion dollars in CBD sales last year (13). But what exactly is CBD? How can it be used? What are the health benefits? What is its role in a cancer fighting plan? Let’s break it down. 

The History of CBD

CBD has been used for thousands of years. It first garnered attention in the US when it was administered as an adjunct treatment for Charlotte Figi, a five-year-old girl with a seizure disorder (20). Since then, dozens of studies and trials on the role of cannabis and epilepsy have been conducted.

What is CBD? 

CBD comes from cannabidiolic acid, or CBDA for short (5). After CBDA is processed at high temperatures, the end product will yield CBD. Depending on the type of Cannabis plant, there can be various amounts of actual CBD in the final product. 

There are three kinds of Cannabis plants that yield CBDA, including the Cannabis indica, ruderalis, and sativa plant types, Of these, the C. sativa variety is the most common (4,6). While CBD itself is not psychoactive, some CBD products also contain Tetrahydrocannabinol (THC), which is psychoactive.  Labels may indicate the “type” of CBD which can help to figure out if the product contains CBD or not (19):

• Type 1: Contains the most THC.

• Type 2: Contains CBD and THC in equal quantities. 

• Type 3: Contains CBD with little to no THC. 

Sellers will typically disclose the CBD and THC content, as well as types, on their packages.

How can CBD be consumed? 

CBD can take a wide range of forms. Most typically, people use CBD as a topical, oral product or inhaled product. If consumed orally, CBD will take longer to reach full effect because it needs to get absorbed into the bloodstream and processed, compared with inhaled and vaping methods (1). However, there are some concerns with lung health and regular inhalation of CBD. More research is needed to properly identify any long-term risks.

Oils, balms, lotions and patches may contain CBD that are absorbed transdermally, or through the skin. However, most topicals only work locally. (7). 

What is CBD used for? 

CBD and THC have many uses including, but not limited to (2, 11, 16, 17 18, 21, 23, 24):

• Pain relief

• Anticipatory nausea relief

• Appetite stimulation

• Mental health conditions

• Skin rashes when applied topically 

• Seizure control

• Multiple Sclerosis pain management 

CBD products may also have terpenoids, giving it a unique smell. Terpenoids are said to have “antifungal, antiviral, anticancer, anti-inflammatory, antihyperglycemic, antiparasitic, antioxidant, and antimicrobial” effects (8).

Can CBD help slow cancer progression? 

CBD may also slow the progression of certain cancers. CBD and THC have the potential to interfere with the cancer cell’s signaling pathways, slowing cancerous growth (14). 

• In gliomas: CBD decreased “tumor size, vascularization, growth and weight” in vitro and “induced tumor regression in vivo” (18).

• In breast cancers, CBD helped “inhibit tumor growth” in mouse models by interfering with cell communication pathways (3).

• In vitro studies found that in prostate cancer cells, CBD “decrease[d] in cell viability, and increase[d] apoptosis” (15).

While the above studies are promising, more clinical trials are needed to verify CBD’s effectiveness and safety in humans. 

Contraindications and Adverse Effects

Since CBD is only regulated when it’s prescribed, most forms are not regulated by the Food and Drug Administration (FDA). Services like the Consumer Lab offer testing information for CBD and THC product content to help consumers make informed choices about the safety and integrity of non-prescription CBD products.

In addition, studies indicate that doses of CBD near 1500 mg or higher usually resulted in “diarrhea, nausea, headache and somnolence”(21). Meanwhile, long-term use may put people at “risk of multiple neuropsychiatric conditions,” like“depression, anxiety and schizophrenia” (11). For products that contain THC there may be an element of dependence and abuse. 

State- to state regulation: 

Explicit CBD laws regarding CBD vary state to state. As of February 2023 (12), 

• 20 states allow recreational use, meaning you can obtain CBD for recreational and medical use freely.

• 15 states allow cannabis for medicinal use, meaning if cleared by a physician, you can use CBD products.

• Cancer is a “qualifying medical condition” in many states like New York that allows patients to use CBD (10).

• 9 states, including 2 states with decriminalized CBD laws, implement mixed use policies, meaning only certain forms are legal. 

• 4 states currently outlaw all CBD products. 

What is hemp? What are hemp seeds and oils? 

Hemp seeds come from the same plant as CBD and typically contain “no more than 0.3% THC”. For comparison, other cannabis plants may have up to 30% THC (9). Hemp seeds are usually used for flavor or nutritional boosts for protein, omega 3s and fiber. 

Since hemp seeds have negligible amounts of both THC and CBD, they are non-psychoactive products. Products derived from hemp seeds, like oils and creams, are non-psychoactive as well. 

The final verdict 

While CBD has been around for thousands of years, clinical trials and human testing are still underway. There are some definite benefits to using CBD such as reducing anticipatory nausea and neuropathic pain. However, long-term safety, proper dosing, food-drug interactions and other related concerns are still being explored. Talk with your healthcare professional to weigh the risks-benefits and decide if CBD is right for you. 

Works Cited

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2. Casey, Sherelle L, and Christopher W Vaughan. “Plant-Based Cannabinoids for the Treatment of Chronic Neuropathic Pain.” Medicines (Basel, Switzerland) vol. 5,3 67. 1 Jul. 2018, doi:10.3390/medicines5030067

3. Elbaz, Mohamad, et al. “Modulation of the Tumor Microenvironment and Inhibition of EGF/EGFR Pathway: Novel Anti-Tumor Mechanisms of Cannabidiol in Breast Cancer.” Molecular Oncology, U.S. National Library of Medicine, Apr. 2015, https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4387115/. 

4. Ferguson, Sian. “Hemp vs. Marijuana: What's the Difference?” Healthline, Healthline Media, 27 Aug. 2020, https://www.healthline.com/health/hemp-vs-marijuana#marijuana. 

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7. Gill, Lisa L. “How to Safely Use CBD: Should You Inhale, Spray, Apply, or Eat It?” Consumer Reports, 26 Aug. 2018, https://www.consumerreports.org/cbd/how-to-use-cbd-inhale-spray-apply-eat/. 

8. Hanuš, Lumír Ondřej, and Yotam Hod. “Terpenes/Terpenoids in Cannabis: Are They Important?” Medical Cannabis and Cannabinoids, Karger Publishers, 10 Aug. 2020, https://www.karger.com/Article/FullText/509733#. 

9. Huizen, Jennifer. “Hemp Plants: Identification, Legality, and More.” Medical News Today, MediLexicon International, 23 July 2021, https://www.medicalnewstoday.com/articles/hemp-plant#vs-other-cannabis. 

10. “Is CBD Oil Legal in New York?” New York Cannabis Information Portal, https://newyorkstatecannabis.org/cbd. 

11. Levinsohn, Erik A, and Kevin P Hill. “Clinical Uses of Cannabis and Cannabinoids in the United States.” Journal of the Neurological Sciences, Elsevier, 30 Jan. 2020, https://www.sciencedirect.com/science/article/pii/S0022510X20300538?via%3Dihub. 

12. “Marijuana Legality by State.” DISA, Feb. 2023, https://disa.com/maps/marijuana-legality-by-state. 

13. Mikulic, Matej. “Total CBD Product Sales U.S. 2014-2022.” Statista, 27 July 2022, https://www.statista.com/statistics/760498/total-us-cbd-sales/. 

14. O'Brien, Kylie. “Cannabidiol (CBD) in Cancer Management.” Cancers, U.S. National Library of Medicine, 10 Feb. 2022, https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8869992/.

15. Ramos JA, Bianco FJ. The role of cannabinoids in prostate cancer: Basic science perspective and potential clinical applications. Indian J Urol. 2012 Jan;28(1):9-14. doi: 10.4103/0970-1591.94942. PMID: 22557710; PMCID: PMC3339795.

16. Rock EM;Limebeer CL;Pertwee RG;Mechoulam R;Parker LA; “Therapeutic Potential of Cannabidiol, Cannabidiolic Acid, and Cannabidiolic Acid Methyl Ester as Treatments for Nausea and Vomiting.” Cannabis and Cannabinoid Research, U.S. National Library of Medicine, 1 Aug. 2021, https://pubmed.ncbi.nlm.nih.gov/34115951/. 

17. Russo, Ethan B. “Cannabis Therapeutics and the Future of Neurology.” Frontiers, Frontiers, 1 Oct. 2018, https://www.frontiersin.org/articles/10.3389/fnint.2018.00051/full#B80. 

18. Seltzer ES, Watters AK, MacKenzie D Jr, Granat LM, Zhang D. Cannabidiol (CBD) as a Promising Anti-Cancer Drug. Cancers (Basel). 2020 Oct 30;12(11):3203. doi: 10.3390/cancers12113203. PMID: 33143283; PMCID: PMC7693730.

19. Sparr-Jaswa, Andrea. “Type I, Type II, Type III: How Science Is Changing the Way the Industry Describes Cannabis Varieties.” Cannabis Business Times, 8 Nov. 2019, https://www.cannabisbusinesstimes.com/news/chemotype-classification-how-science-is-changing-the-way-the-industry-describes-cannabis-varieties/. 

20. Specchio, Nicola, et al. “Source of Cannabinoids: What Is Available, What Is Used, and Where Does ...” Wiley Online Library, 3 Mar. 2020, https://onlinelibrary.wiley.com/doi/full/10.1684/epd.2019.1121. 

21. Taylor L, Gidal B, Blakey G, Tayo B, Morrison G. A Phase I, Randomized, Double-Blind, Placebo-Controlled, Single Ascending Dose, Multiple Dose, and Food Effect Trial of the Safety, Tolerability and Pharmacokinetics of Highly Purified Cannabidiol in Healthy Subjects. CNS Drugs. 2018 Nov;32(11):1053-1067. doi: 10.1007/s40263-018-0578-5. Erratum in: CNS Drugs. 2019 Apr;33(4):397. PMID: 30374683; PMCID: PMC6223703.

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