Although history shows that cannabis has been used for medicinal, recreational and even religious purposes for at least 5,000 years, much is still misunderstood about how the plant’s phytocannabinoids, such as cannabidiol (CBD) and tetrahydrocannabinol (THC), react with the endocannabinoid system of the human body.
This is mostly thanks to the US government's active prohibition of cannabis, which in turn had limited research into the therapeutic benefits of the plant. However, this hasn’t stopped people from using cannabis and its cannabinoids, such as CBD, to treat an incredibly wide range of conditions, from mental illnesses and neurological disorders to digestive and immune disorders, and even cancer.
It’s enough to make you wonder how just one plant could really treat so many ailments. This is where the endocannabinoid system comes in.
How CBD and Other Cannabinoids Interact With the Human Body
In 1988, two scientists conducting a government-funded study at the St. Louis University of Medicine to prove the harmful effects of cannabis ended up making a significant discovery: the mammalian brain contains receptor sites that respond to the compounds of the cannabis plant known as phytocannabinoids. Even more interesting is that these newly discovered receptor sites turned out to be the most abundant type of neurotransmitter receptors found in the brain.
By 1990, a team of scientists at the National Institute of Mental Health had mapped out the DNA sequence of these newly discovered receptor sites to determine how they interact with the brain both together and separately. This, in turn, lled to another significant discovery: the human body actually produces several of its own cannabinoids.
Termed endocannabinoids, human-produced cannabinoids are quite similar to the phytocannabinoids found in the cannabis plant, with the biggest difference being where they come from (plants vs. humans). Further studies on both human- and plant-produced cannabinoids and how they interact with each other ended up leading to yet another significant discovery: a new physiological system found in living systems, now known as the endocannabinoid system.
The Endocannabinoid System (ECS) Explained
From what has been learned about the endocannabinoid system thus far, it is believed to play an important role in both establishing and maintaining health in humans and other living creatures, from dogs to fish. It is believed to serve as a regulator for several important functions, from sleep, mood and memory to appetite, reproduction and pain sensation by maintaining homeostasis.
Translated from the Greek words “same” and “steady”, homeostasis is a fundamental concept of biology in which living systems maintain a stable internal environment that is necessary for survival. For example, the pancreas’s role in the endocrine system is to regulate blood sugar levels. When blood sugar levels are neither two low nor too high, they are being properly regulated and maintained to achieve homeostasis.
The endocannabinoid system is mostly comprised of three key components that work together to maintain homeostasis:
The two main eCBs produced throughout the body are anandamide (AEA), also known as the “bliss molecule” due to the cannabinoid’s mood-enhancing properties, and 2-arachidonoylglycerol (2AG). Rather than being stored and used later like other molecules in the body, these endocannabinoids are produced and used on demand when needed.
How CBD Interacts with the Endocannabinoid System’s CB Receptors
The second most well-known phytocannabinoid next to THC is, of course, CBD and it has a unique role when it comes to the endocannabinoid system, specifically in how it interacts with CB receptors.
So far, researchers have been able to identify two main cannabinoid receptors, simply named cannabinoid receptor 1 (CB1) and cannabinoid receptor 2 (CB2). The role of CB1 receptors is to maintain a healthy functioning brain, while CB2 receptors serve the immune system to help regulate inflammation and the body’s immune response. Phytocannabinoids, like THC, bind to these receptors like a lock and key. CBD, on the other hand, reacts differently.
Rather than binding to CB receptors like other cannabinoids, scientists believe CBD instead serves as a modifier in that it either blocks or partially binds to CB receptors to help regulate both inter- and intra-cellular communication. In other words, CBD either blocks or limits the absorption of cannabinoids to enhance the body’s ability to produce and absorb endocannabinoids. It basically acts like the body’s own hall monitor, directing its fellow cannabinoids to where they need to be.
For example, prescription drugs used to treat mental ailments such as schizophrenia, Parkinson’s and depression are formulated with chemicals that bind to dopamine D2 receptors (D2R) to help alleviate symptoms, and CBD has been shown to assist in the binding process.
The Future of CBD
When it comes to laws and regulations, CBD still falls under a gray area despite its newly legal status under the Farm Bill of 2018, which removed hemp and derivatives of cannabis containing extremely low concentrations of THC (no more than 0.3 percent) from the definition of marijuana in the Controlled Substances Act (CSA). The 2018 Farm Bill also preserved the FDA’s authority over hemp and cannabis derivatives, which means CBD brands are prohibited from marketing their products for therapeutic purposes without FDA approval.
So far, the FDA has only approved one CBD-infused product for therapeutic purposes.