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The Endocannabinoid System

Dr. Raphael Mechoulam has been studying cannabis and cannabinoids since the early 1960’s and is widely considered to be the godfather of scientific and medical cannabis research. He and his team of researchers have been credited with the many important discoveries.

His work on cannabinoids led to the discovery of the Endogenous Cannabinoid System (ECS) in 1992. The ECS is a network of cannabinoid receptors, molecules called endogenous cannabinoids (endocannabinoids), and enzymes that create and degrade endocannabinoids. ECS receptors are present throughout the body, including the brain, organs, connective tissues, glands and immune cells. The main function of the ECS is to work throughout all systems of the body to achieve homeostasis.

Homeostasis is essentially a state of balance; a stable internal environment that is able to resist changes in the environment and maintain harmony inside the various systems of the body. Thus, the ECS can positively affect brain functions including memory, mood, perception of pain, cognition, emotion, motor functions, anti-inflammatory function along with assisting brain development and protection.

Endocannabinoid Receptors

Endocannabinoid receptors are abundant throughout the human body. They are found in the brain, spinal cord, connective tissue, immune system, bones, skin, heart, kidneys, blood vessels, and reproductive organs. Current research shows that there are more endocannabinoid receptors than any other neurotransmitter receptors in the body! This may help explain why the ECS plays such a powerful role in modulating the various physiological functions of the body.

Two main endocannabinoid receptors have been identified and have been classified as CB1 and CB2 receptors. It was once thought that CB1 receptors were found only in the nervous system and CB2 receptors were found only in the immune system. We now know that both of these receptors are found throughout the body, although CB1 receptors are found in higher concentrations in the central nervous system and CB2 receptors are more abundant in the immune system.

These receptors are located on the surface of cells and play the role of communicating messages into the cells. In this way, they provide an important function in the process of maintaining homeostasis in the body.


Endocannabinoids (endogenous cannabinoids) are molecules present throughout the body, which bind to and activate endocannabinoid receptors. The body naturally produces endocannabinoids, and Dr Mechoulam’s team in Jerusalem discovered two primary endogenous cannabinoids.

The first, commonly known as Anandamide (arachidonoylethanolamine or AEA), was discovered only in 1992. The other one is called 2-arachidonoylglycerol, commonly called 2-AG.

Both of these endocannabinoids are used by the body to bind to cannabinoid receptors, thus activating them and promoting homeostasis. These molecules are later broken down by enzymes known as FAAH (fatty acid amide hydrolase) and MAGL (monoglycerol lipase). If endocannabinoids are degraded too quickly, this can result in endocannabinoid deficiency, affecting the body’s ability to maintain homeostasis.


Phytocannabinoids are molecules that are very similar to endocannabinoids but they are produced in the plant world. These plant substances have the ability to interact with and stimulate our cannabinoid receptors. The most well known and studied phytocannabinoids are Delta 9 THC (Tetrahydrocannabinol) and CBD (Cannabidiol). There are over 100 known cannabinoids in the cannabis plant, only a few of which have been studied so far. Phytocannabinoids are also produced naturally in other plants like echinacea, cacao and many others.

Scientific research shows that phytocannabinoids can signal the body to produce more endocannabinoids as well as build more cannabinoid receptors. The body recognizes phytocannabinoids and responds to them in a similar way to endocannabinoids. So when the body experiences cannabinoid deficiency, phytocannabinoids can assist by making up for the deficiency while also encouraging the body to produce more natural endocannabinoids.

The quote above is quite a statement, coming from a retired cardiothoracic and vascular surgeon. What is surprising is that based on a survey conducted by Dr. Allen and Cannabis Digest, as of just a few years ago, only 13% of 157 certified medical schools surveyed actually teach any type of endocannabinoid science to future physicians. Although medical science has been slow to act on the discovery of the endocannabinoid system, there is growing evidence that understanding the ECS and its role in modulating homeostasis is key to treating a number of chronic illnesses.

Cannabinoid Deficiency

In 2008, Dr. Ethan Russo theo