Cannabinoids are a diverse class of chemical compounds that occur naturally in the human body (endocannabinoids) and cannabis plants (phytocannabinoids), and interactions with the endocannabinoid system (ECS) trigger various physiological actions. Among the 500 or so natural components in cannabis, more than 100 are classified as phytocannabinoids. Tetrahydrocannabinol (THC) is the best-known compound due to its psychoactive qualities, while cannabidiol (CBD) appears to play the most significant role in the plant’s medicinal benefits. Other key phytocannabinoids include the following:

  • Cannabigerols (CBG)

  • Cannabichromenes (CBC)

  • Cannabinol (CBN)

  • Cannabinodiol (CBL)

CBD, which does not produce psychoactive effects, is often isolated for medical use, but some clinical studies suggest that cannabinoids are mutually enhancing and provide the best results in whole-plant form. CBN, another cannabinoid gaining interest with medical researchers, is a natural sedative that appears to have analgesic, anti-inflammatory and anti-convulsive properties. Endocannabinoids, meanwhile, include anandamide and 2-Arachidonoylglycerol (2-AG), and they play roles in metabolism, food intake, memory, sensory perception, central nervous system development and synaptic plasticity.

Cannabinoid Receptors

Cannabinoid receptors are embedded in the cellular membrane in the central nervous and immune systems as well as in various organs. Both endo- and phytocannabinoids bind to these receptors or influence them indirectly. As external environments and stressors change, the ECS helps the body maintain a stable biological environment, or homeostasis. The importance of the system is such that drug companies manufacture synthetic cannabinoids to replicate artificially the natural processes produced by the body and cannabis plants. The pharmaceutical product is widely considered inferior.
The two main ECS receptors are type 1 (CB1) primarily in the central and peripheral nervous system and type 2 (CB2) primarily in the immune system. Some cellular tissue contains both types performing their respective actions. While THC binds directly to cannabinoid receptors, CBD affects them indirectly by stimulating endocannabinoid production in the body and suppressing the enzyme that metabolizes the natural chemicals. Furthermore, CBD and CBN are both examples of phytocannabinoids that bind to non-cannabinoid receptors, including 5-HT1A (serotonin), TRPV1 (pain, inflammation) and adenosine A2A (cardiovascular, respiratory).

How Cannabinoids Work

The ECS is responsible for physiological processes like appetite, pain sensation, mood and memory, and cannabinoids mediate communication between various cells and systems. Its receptors, when activated, trigger various chemical, natural and pharmacological effects relating to how we feel, both mentally and physically. Phytocannabinoids work their magic by imitating the endocannabinoids produced naturally in the body.
Some researchers suggest the system serves as a bridge between the brain and the body, and the area of the brain with which the cannabinoids bind dictates the way the cannabis will affect the person. These areas include the limbic system, which affects memory, cognition and psychomotor performance; the mesolimbic pathway, the part of the brain associated with feelings of reward; and various parts of the brain associated with pain perception. Medical cannabis treatments are largely based on the practice of aiming the right cannabinoids at the right receptors.
Interestingly, the cannabis plant also uses cannabinoids to promote its own health. The compounds have antioxidant properties that protect the leaves and flowering structures from ultraviolet radiation. In other words, cannabinoids neutralize the harmful free radicals generated by UV rays, protecting the cells. In humans, free radicals cause aging, cancer and impaired healing, and the medical community has long promoted antioxidants as a natural way to reduce free radical harm.

Cannabis as Medicine

Cannabis, with its naturally occurring cannabinoids, has been used for medicinal purposes for thousands of years. The U.S. Food and Drug Administration (FDA) has yet to approve cannabis as a treatment for any medical condition. However, the National Institutes of Health (NIH) owns patent No. 6630507 on the neuroprotectant properties of cannabinoids, and the National Institute on Drug Abuse (NIDA) says whole-plant marijuana appears to slow cancer growth and potentially kill certain types of cancer cells. NIDA also acknowledged that THC reduces nausea and muscle control problems, while CBD has therapeutic potential for childhood epilepsy, seizures, mental health disorders, addiction and other serious conditions. Both cannabinoids provide relief from pain and inflammation.
The ECS is named after the cannabis plant, and researchers studying the plant actually led to the discovery of the system. Fittingly, researchers are finding that other plant life, such as echinacea, also contain helpful cannabinoids. A side benefit from research into cannabis compounds is a better understanding of how other medicinal herbs might also promote physical and mental health.