What Is the Difference Between CBD and THC?

  • Cannabidiol (CBD) and tetrahydrocannabinol (THC) are cannabinoids or compounds found in hemp and marijuana. Hemp has a high CBD content, while marijuana has a high THC content, which induces psychoactive effects(1).
  • A cross-sectional study of cannabidiol users published in Cannabis and Cannabinoid Research highlighted CBD’s therapeutic benefits for pain, anxiety, depression, and sleep disorders(2)
  • A study showed that THC has the potential to reduce nausea in patients undergoing cancer chemotherapy and stimulate appetite in patients with wasting syndrome caused by acquired immunodeficiency syndrome (AIDS)(3).
  • CBD’s side effects include tiredness, diarrhea, and reduced appetite/weight(4). Meanwhile, THC can cause changes in mood, altered senses, and impaired memory(5).
  • Users should research each state’s laws and consult a health professional before buying cannabis products to ensure safe and proper use.

Chemical Structure of CBD and THC

CBD and THC’s chemical composition is the same: 21 carbon atoms, 30 hydrogen atoms, and 2 oxygen atoms, or C21H30O2. Both compounds also contain a molecular weight of 314.5 g/mol(6-7).

However, CBD and THC differ in their arrangement of atoms, therefore each compound produces different effects on the body.

Sources of CBD and THC

CBD is a non-psychoactive compound found in the Cannabis sativa plant. While CBD can be extracted from either hemp or cannabis (marijuana), CBD is more abundant in hemp.

CBD is available in different forms, including tinctures, topicals, gummies, cookies, supplements, and vapes.

Like CBD, THC can come from either marijuana or hemp. As THC has a psychoactive component, it is only legal in states that allow recreational use or medical use of marijuana.

Meanwhile, for hemp to be considered legal, it should contain no less than 0.3% of THC(8).

THC is the most psychoactive component contributing to the behavioral toxicity of cannabis plants(9). This compound causes users to experience euphoria when taking cannabis products.

THC is also available in tinctures, oils, capsules, vapes, and edibles.

Full-Spectrum, Broad-Spectrum, and CBD Isolates

Before purchasing a CBD product, users should determine if the variety is full-spectrum, broad-spectrum, or a CBD isolate. Knowing the corresponding effects of these varieties will help users determine what suits their needs.

The full-spectrum products contain all phytochemicals, including CBD, trace amounts of cannabinoids, terpenes, and other minerals found in the cannabis plant. When all of these compounds interact, they produce an “entourage effect” that is more efficient than isolated components(10).

Although full-spectrum products have low THC levels, THC’s presence may still be detected in a drug test if usage is frequent.

Meanwhile, the broad-spectrum variety contains different cannabinoids, except for THC. Thus, broad-spectrum products are suited to those who do not want the psychoactive properties of THC.

As they contain a broad range of cannabinoids, broad-spectrum CBD products also produce the “entourage effect.”

Lastly, CBD isolates are pure CBD extracted separately from all other cannabinoids. Hence, it has the highest concentration of CBD.

CBD isolates are suited to those who want to maximize all benefits of CBD. However, this variety does not carry the health benefits produced by the “entourage effect.”

How CBD and THC Interact with the Endocannabinoid System

Both CBD and THC interact with the endocannabinoid system (ECS). Composed of cannabinoid receptors, the ECS plays a crucial role in developing the central nervous system and performing various biological functions, like mood regulation, pain perception, stress management, and immune response(11).

Cannabinoid receptors have two types: CB1 and CB2. CB1 receptors are widely dispersed in the brain and other parts of the body(12).

CB1 receptors also play an essential role in pain sensation, memory processing, motor regulation, appetite, mood, and sleep. Also, CB1 receptors’ activation has been linked to neuroprotective responses.

Thus, CB1 receptors has the potential to help treat neurodegenerative conditions like Alzheimer’s disease, Parkinson’s disease, and multiple sclerosis(13).

Meanwhile, CB2 receptors are mainly found on cells in the immune system and its associated structures. When these CB2 receptors are activated, they elicit a response that helps fight inflammation and treat certain medical conditions, like Chron’s disease, arthritis, and inflammatory bowel syndrome(14)

The human body naturally produces cannabinoids called endocannabinoids, which interact with the receptors to maintain balance. However, phytocannabinoids, like CBD and THC, also effectively stimulate CB1 and CB2 receptors(15).

Thus, CBD and THC can help the endocannabinoid system properly maintain its function if endocannabinoids are lacking in the body.

While both THC and CBD interact with the ECS, they do so differently. THC initiates a psychological response via the endocannabinoid system’s CB1 receptors.

Once activated, the CB1 receptor produces a psychoactive effect.

CBD, however, does not bind with the CB1 receptors. Thus, it does not produce psychoactive effects.

Medical Benefits of CBD and THC

According to the National Institutes of Health (NIH), products that contain cannabinoids can help treat nausea and vomiting caused by cancer chemotherapy, loss of appetite, and weight loss linked to HIV/AIDS(16).

The use of cannabinoids has also been suggested to be beneficial in treating chronic pain and multiple sclerosis.

Common Uses for CBD

  • Anti-anxiety
  • Anti-inflammatory
  • Antipsychotic
  • Pain relief
  • Improved sleeping habits

Various studies have shown promise with the use of CBD in treating neuropsychiatric disorders, including epilepsy and schizophrenia. CBD may also provide calming effects and help relieve anxiety. CBD may also provide calming effects and help relieve anxiety(17).

Common Uses for THC

  • Increased appetite
  • Reduced nausea and vomiting
  • Pain relief
  • Muscle spasticity

Studies have shown that THC may also act as a muscle relaxant, anti-inflammatory, and anti-anxiety(18)

However, despite the suggested health benefits of CBD and THC, more research is needed to explore their potential in treating medical conditions. 

Further studies would also provide conclusive evidence that the two compounds work better when combined.

In a review of the role of cannabis within an emerging perspective of schizophrenia, CBD was suggested to be a useful supplemental therapy in schizophrenia.

The same review emphasized that CBD can block the temporary symptoms of psychosis exacerbated by THC. This finding suggests that the combined administration of THC and CBD may produce better effects(19).

Legality of CBD and THC

The laws on cannabis use are evolving, especially in the United States. With the legalization of industrial hemp, the 2018 Farm Bill also states that cannabis plants and derivatives containing no more than 0.3% THC are no longer considered controlled substances under federal law.

However, the Drug Enforcement Act (DEA) still considers CBD to be a Schedule I controlled substance. Also, the Food and Drug Administration (FDA) regulates “products containing cannabis or cannabis-derived compounds(20).”

According to the FDA, products containing THC or CBD cannot be sold legally as dietary supplements. Currently, the FDA approves Epidiolex, Marinol, and Syndros only(21).

Epidolex is a purified form of CBD derived from cannabis, approved for treating seizures associated with Lennox-Gastaut syndrome or Dravet syndrome, which are two severe kinds of epilepsy in children.

Marinol and Syndros, prescribed in pill form, are approved by the FDA to treat anorexia associated with weight loss in AIDS patients(22).

As there are no other FDA-approved CBD products, users should buy CBD in states that allow recreational use or medical use of marijuana.

Side Effects of CBD and THC

Studies showed that chronic use of CBD and even high doses of up to 1,500mg/day was well tolerated by humans(23).

While CBD and THC produce medical and therapeutic benefits, these compounds can also cause some side effects, especially when taken frequently. Hence, consumers should consult a doctor before taking cannabis- and hemp-derived products.

Side Effects of CBD

CBD can cause some negative side effects, including decreased fertilization capacity, inhibition of hepatic drug metabolism, and reduced activities of p-glycoprotein and other drug transporters(24).

According to Mayo Clinic, other side effects include the following(25):

  • Dry mouth
  • Diarrhea
  • Reduced appetite
  • Tiredness
  • Fatigue
  • Drowsiness
  • Changes in weight

Side Effects of THC

THC is the mind-altering compound in marijuana, responsible for producing intoxicating effects.

THC acts on brain cell receptors that react to other THC-like compounds affecting normal brain development.

The use of THC can have corresponding side effects. These include(26)

  • Changes in mood
  • Altered senses
  • Impaired body movement
  • Impaired memory
  • Breathing difficulties
  • Red eyes
  • Hallucinations, especially when taken in high dosage
  • Psychosis
  • Risks for the fetus when taken by pregnant women

Additionally, the use of cannabis can result in cannabis use disorder, which includes symptoms, like lack of control, craving, and withdrawal(27).

High THC use can also disrupt brain development, especially in vulnerable adolescents consuming large amounts of THC(28).


CBD and THC are two of the hundred compounds found in cannabis plants. While CBD is more dominant in hemp plants, THC is more dominant in marijuana.

The main difference between these compounds is that THC is psychoactive, making users feel “high,” while CBD is non-psychoactive, which means there is no euphoric effect. 

CBD products have been gaining popularity because of its known therapeutic benefits, including pain relief, anti-anxiety, and sleeping aid(29)

THC is also reported to have therapeutic benefits, including increased appetite, pain relief, and muscle relaxation(30).

While CBD oil is generally safe for humans, it can cause negative side effects, including diarrhea, lost appetite, and fatigue, as studies mentioned above have suggested(31).

THC can also produce side effects, like breathing problems, impaired body movement, and altered senses(32)

Thus, users should seek professional advice and study each state’s laws before consuming any products containing CBD and THC.

  1. Sharma, P., Murthy, P., & Bharath, M. M. (2012). Chemistry, metabolism, and toxicology of cannabis: clinical implications. Iranian journal of psychiatry, 7(4), 149–156. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3570572/ 
  2. Corroon, J., & Phillips, J. A. (2018). A Cross-Sectional Study of Cannabidiol Users. Cannabis and cannabinoid research, 3(1), 152–161. doi.org/10.1089/can.2018.0006. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6043845/#:~:text=Results%3A%20Almost%2062%25%20of%20CBD,reported%20%E2%80%9Cnot%20very%20well.%E2%80%9D 
  3. National Institute of Health. (2020, Jul.). Marijuana Research Report. Retrieved from https://www.drugabuse.gov/publications/research-reports/marijuana/marijuana-safe-effective-medicine 
  4. Iffland, K., & Grotenhermen, F. (2017). An Update on Safety and Side Effects of Cannabidiol: A Review of Clinical Data and Relevant Animal Studies. Cannabis and cannabinoid research, 2(1), 139–154. doi.org/10.1089/can.2016.0034. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5569602/ 
  5. National Institute of Health. (2019, Dec.). Marijuana Drug Fact. Retrieved from https://www.drugabuse.gov/publications/drugfacts/marijuana 
  6. Biotechnology Information (2020). PubChem Compound Summary for CID 644019, Cannabidiol. https://pubchem.ncbi.nlm.nih.gov/compound/Cannabidiol 
  7. National Center for Biotechnology Information (2020). PubChem Compound Summary for CID 2978, delta9-Tetrahydrocannabinol. https://pubchem.ncbi.nlm.nih.gov/compound/delta9-Tetrahydrocannabinol 
  8. U.S. Food and Drug Administration. (2020, Oct. 1). FDA Regulation of Cannabis and Cannabis-Derived Products, Including Cannabidiol (CBD). Retrieved from https://www.fda.gov/news-events/public-health-focus/fda-regulation-cannabis-and-cannabis-derived-products-including-cannabidiol-cbd 
  9. Sharma, P., Murthy, P., & Bharath, M. M. (2012). Chemistry, metabolism, and toxicology of cannabis: clinical implications. Op. Cit.
  10. Russo E. B. (2019). The Case for the Entourage Effect and Conventional Breeding of Clinical Cannabis: No “Strain,” No Gain. Frontiers in plant science, 9, 1969. doi.org/10.3389/fpls.2018.01969. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6334252/ 
  11. Skaper, S. D., & Di Marzo, V. (2012). Endocannabinoids in nervous system health and disease: the big picture in a nutshell. Philosophical transactions of the Royal Society of London. Series B, Biological sciences, 367(1607), 3193–3200. doi.org/10.1098/rstb.2012.0313. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3481537/
  12. Manzanares, J., Julian, M., & Carrascosa, A. (2006). Role of the cannabinoid system in pain control and therapeutic implications for the management of acute and chronic pain episodes. Current neuropharmacology, 4(3), 239–257. doi.org/10.2174/157015906778019527. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2430692/ 
  13. Education Collaboration Hope. (2017, Apr. 18). A Look at the Endocannabinoid System’s CB1 and CB2 Receptors. Retrieved from https://echoconnection.org/look-endocannabinoid-systems-cb1-cb2-receptors/
  14. Ibid. 
  15. Ibid. 
  16. National Institutes of Health. (2019, Nov.) Cannabis (Marijuana) and Cannabinoids: What You Need To Know. Retrieved from https://www.nccih.nih.gov/health/cannabis-marijuana-and-cannabinoids-what-you-need-to-know 
  17. Shannon, S., Lewis, N., Lee, H., & Hughes, S. (2019). Cannabidiol in Anxiety and Sleep: A Large Case Series. The Permanente journal, 23, 18–041. doi.org/10.7812/TPP/18-041. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6326553/ 
  18. Russo E. B. (2008). Cannabinoids in the management of difficult to treat pain. Therapeutics and clinical risk management, 4(1), 245–259. doi.org/10.2147/tcrm.s1928. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2503660/
  19. Diviant, J. P., Vigil, J. M., & Stith, S. S. (2018). The Role of Cannabis within an Emerging Perspective on Schizophrenia. Medicines (Basel, Switzerland), 5(3), 86. doi.org/10.3390/medicines5030086. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6164121/ 
  20. U.S. Food and Drug Administration. (2020, Oct. 1). FDA Regulation of Cannabis and Cannabis-Derived Products, Including Cannabidiol (CBD). Op Cit.
  21. Ibid.
  22. Ibid.
  23. Bergamaschi, M. M., Queiroz, R. H., Zuardi, A. W., & Crippa, J. A. (2011). Safety and side effects of cannabidiol, a Cannabis sativa constituent. Current drug safety, 6(4), 237–249. doi.org/10.2174/157488611798280924. https://pubmed.ncbi.nlm.nih.gov/22129319/
  24. Ibid.
  25. Bauer, B. A. (2018, Dec. 20). What are the benefits of CBD — and is it safe to use? Retrieved from https://www.mayoclinic.org/healthy-lifestyle/consumer-health/expert-answers/is-cbd-safe-and-effective/faq-20446700 
  26. National Institute of Health. (2019, Dec.). Marijuana Drug Fact. Op Cit. 
  27. National Institutes of Health. (2019, Nov.) Cannabis (Marijuana) and Cannabinoids: What You Need To Know. Op Cit.
  28. Manseau, M. W., & Goff, D. C. (2015). Cannabinoids and Schizophrenia: Risks and Therapeutic Potential. Neurotherapeutics: the journal of the American Society for Experimental NeuroTherapeutics, 12(4), 816–824. doi.org/10.1007/s13311-015-0382-6. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4604190/ 
  29. Corroon, J., & Phillips, J. A. (2018). A Cross-Sectional Study of Cannabidiol Users. Op Cit.
  30. Russo E. B. (2008). Cannabinoids in the management of difficult to treat pain. Op Cit.
  31. Bauer, B. A. (2018, Dec. 20). What are the benefits of CBD — and is it safe to use? Op Cit. 
  32. National Institute of Health. (2019, Dec.). Marijuana Drug Fact. Op Cit.


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