The endocannabinoid system works in conjunction with compounds in cannabis (both hemp and marijuana) to help the body stay in balance.

The Endocannabinoid System: What It Is and Why It's Important

By Kristi Pahr

The cannabis plant and its constituent compounds like CBD, CBG, and THC, have received a boatload of attention over the last several years, especially in wellness and medical circles. We know it works as a therapeutic agent for many conditions, but many people don’t know why it works. As it turns out, in addition to the digestive, circulatory, and nervous systems, the ones we all learned about in school, there’s another system —  the endocannabinoid system (ECS). It works in conjunction with compounds in cannabis (both hemp and marijuana) to help the body stay in balance. 

Discovery of the Endocannabinoid System

The endocannabinoid system is comprised of three basic parts: cannabinoid receptors, endocannabinoid molecules, and enzymes that help break down cannabinoid molecules.


Because of its status as a Schedule 1 controlled substance, cannabis was not a widely researched substance in the 20th century. Despite its popularity for recreational use, the mechanism by which it worked, the endocannabinoid system, was not discovered until 1988. It was discovered by researchers Allyn Howlett and William Devane from the St. Louis University School of Medicine, who determined that cannabinoid neurotransmitters are the most plentiful neurotransmitters found in the brain — and not just the human brain. Cannabinoid receptors are found in all vertebrates.

How Does the ECS Work?

The ECS is comprised of three basic parts: cannabinoid receptors, endocannabinoid molecules, and enzymes that help break down cannabinoid molecules. Cannabinoid receptors are found not only in the brain and nervous system but in every system in the body. They are located on cell surfaces where they monitor what’s going on around them. While there are several types of cannabinoid receptors, CB1 and CB2 were the first discovered and have garnered the most research so are the most well-known. 

CB1 and CB2 Receptors

CB1 receptors are found mainly in the nervous system. They work with THC molecules and are responsible for the euphoric feeling associated with marijuana consumption. CB2 molecules are found elsewhere in the body, though they are present in the brain and nervous system as well. 

Endocannabinoid molecules are compounds created within the body (endo means within) that interact with cannabinoid receptors. The two major endocannabinoids, anandamide and AG-2, are produced by the body when and where in the body they are needed. They attach to cannabinoid receptors and can produce effects ranging from pain relief to quelling nausea and vomiting, and they are key components in our body’s ability to maintain overall health.

The final piece of the ECS puzzle is metabolic enzymes. These are chemicals that break down endocannabinoids to ensure they aren’t lingering on the receptor sites longer than they’re needed. This is different from many other molecules and neurotransmitters in the body that can be produced and stored for later use. Endocannabinoids are quick to act and quick to dissipate.


Cannabinoid molecules don’t only come from inside our bodies. Plant-based cannabinoids, like THC and CBD, are called phytocannabinoids (phyto means plant) and are found in a range of plant species like black pepper, salvia, brassicas vegetables like broccoli and kale, and of course, Cannabis sativa. While these other plants produce cannabinoids, the cannabis plant produces them in significantly higher quantities, making it the most reliable source for obtaining them.

Obviously the majority of plants don’t contain THC – you aren’t going to experience psychoactive effects from eating broccoli for dinner – but the phytocannabinoids present in them do interact with cannabinoid receptors within the body.

Cannabinoid Supplementation

Phytocannabinoids, like CBD, THC, and CBG, can be extracted from cannabis in a few different ways to maintain the integrity and potency of the compounds. The extracts are then packaged and shipped to consumers for use in managing a variety of conditions or just as a daily supplement for overall health. Cannabinoid supplementation, according to the National Center for Complementary and Integrative Health (NCCIH), has been found to be useful as a therapeutic agent for a number of conditions, including chronic pain, depression, PTSD, irritable bowel syndrome and irritable bowel disease, epilepsy, multiple sclerosis, and sleep problems. Additionally, there is early research in Brain, Behavior, and Immunology looking at whether it may have some potential benefits with COVID-19.

Some scientists believe that low levels of endocannabinoids or endocannabinoid system dysfunction can result in a condition known as clinical endocannabinoid deficiency (CECD). A study published in 2016 that collated and reviewed over 10 years of research suggests that CECD could be responsible for the development of migraine, IBS, and fibromyalgia. 

Though more research is needed, it’s possible that supplementation with phytocannabinoids like THC, CBD, or CBG might be the answer to these difficult to diagnose and difficult to manage health conditions.

The Take-Home Message

The ECS is a vital component in maintaining health and well-being in all vertebrate species. Though more research is necessary to determine how best to improve ECS function and which cannabinoids help what conditions specifically, there is no doubt that a well functioning ECS improves overall health and that supplementation with phytocannabinoids can improve the quality of life of those with many chronic health conditions.


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Kristi Pahr is a freelance health and wellness writer and mother of two who spends most of her time caring for people other than herself. She is frequently exhausted and compensates with an intense caffeine addiction. Her work has appeared in Good Housekeeping, Real Simple, Men’s Health, and many others.


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