Key takeaways:
The endocannabinoid system, or ECS, is a group of messengers and binding sites located throughout the body. It helps regulate your appetite, memory, and immune system. It also controls your sleep cycle and helps you manage stress.
Messengers in the ECS are called cannabinoids. Your body makes its own cannabinoids, but they can also be found in the cannabis plant. Some of the medical and recreational effects of cannabis are due to how it interacts with the ECS.
You can help your ECS work its best by reducing stress, exercising regularly, and eating healthy fats.
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When it comes to the human body, you’ve likely heard of the nervous system, cardiovascular system, and digestive system. But we also have a lesser-known system that wasn’t discovered until the late 1980s. It’s called the endocannabinoid system, or ECS for short. And it plays a key role in keeping our body functioning properly.
The ECS is most often associated with cannabis. That’s because cannabis works in the body by interacting with the ECS. But as researchers continue to learn about the endocannabinoid system and how it works, it’s become more clear that its connection to cannabis is just one part of its story.
What is the endocannabinoid system?
The endocannabinoid system, or ECS, is a group of messengers and targets that are located throughout your body. Unlike other systems in the body, the ECS has receptors (binding sites) almost everywhere. This includes your brain, skin, and nerves. You also have ECS receptors in your bones, muscles, and blood cells.
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ECS receptors are also called cannabinoid receptors, or CB1 and CB2 for short. CB1 receptors are mainly located in the brain and spinal cord. But they’re also located in most organs, fat cells, and other tissues throughout the body. CB2 receptors are mainly found within the immune system.
A cannabinoid is any messenger that binds to cannabinoid receptors — more on that next.
What are cannabinoids?
Cannabinoids are chemicals that bind to cannabinoid receptors in the ECS. They’re named after the cannabis plant because the first cannabinoid identified by researchers came from cannabis. In fact, the ECS itself was discovered by tracking THC (tetrahydrocannabinol, an active ingredient in cannabis) to see what it attached to in the body.
There are three main types of cannabinoids:
Endocannabinoids: These are cannabinoids made by the body. The two main endocannabinoids are anandamide and 2-AG (2-arachidonoyl glycerol).
Phytocannabinoids: These are cannabinoids made by plants. Cannabis is the main example. It makes cannabinoids such as THC and CBD (cannabidiol). But other plants make cannabinoids, too.
Synthetic cannabinoids: These are artificial cannabinoids made in a lab.
How does the endocannabinoid system work?
The ECS plays a major role in almost all of your bodily functions. Much like an air traffic control tower, the ECS keeps your systems in balance (homeostasis). The main functions of the ECS are often summarized in five words:
Eat: Regulates appetite, metabolism, and digestion
Sleep: Helps regulate the sleep/wake cycle and REM sleep
Relax: Regulates anxiety and stress as well as pain and muscle tension
Protect: Regulates immune system function
Forget: Regulates memory and learning
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Your body makes endocannabinoids on demand, right when they’re needed. They bind to a target receptor, like a key fitting into a lock. When this happens, certain processes in your body get turned on or off. After that, endocannabinoids are quickly broken down and removed.
Here’s a simple example of the ECS in action: If you cut your hand, nerve cells send a pain signal to your brain to alert you that something’s wrong. Once your body responds to the damage and sends white blood cells to heal the cut, there’s no need for pain anymore. So the body releases anandamide. It binds to cannabinoid receptors and turns off the pain signal, putting your body back into balance.
Good to know: Endocannabinoids are released and broken down very quickly. They don’t hang around in the body for long periods of time — just when they’re needed. But other types of cannabinoids work differently. Since they’re not made by the body, they’ll bind to receptors whenever you ingest them. And since the body doesn’t make specific proteins to break down plant or lab-made cannabinoids, they can last much longer in the body than endocannabinoids do.
What is endocannabinoid deficiency?
Clinical endocannabinoid deficiency (CED) is a theory that certain health conditions may be caused by an ECS that’s not working properly.
Research has shown that CED is likely connected to chronic migraines, fibromyalgia, and irritable bowel syndrome. It’s also possible that CED may play a role in the development of schizophrenia, Huntington’s disease, and other mental health conditions. More research is being done to determine what role the ECS plays in these and other health conditions.
The reason this matters is that once we better understand what causes a certain health condition, the easier it is to find ways to treat it. So researchers are focusing on cannabis and other medications that interact with the ECS to help treat CED-related conditions.
How does cannabis interact with the endocannabinoid system?
As mentioned, the phytocannabinoids in cannabis (THC, CBD, and others) bind to ECS receptors. So they can increase or decrease ECS activity in the body. And since ECS receptors are located throughout the body, cannabis can affect a lot of different functions. This helps explain why cannabis may help treat such a wide variety of different symptoms and health conditions.
How does THC interact with this system?
One of the most well-known effects of THC is its ability to cause euphoria (a positive mood). This feeling happens when THC binds to CB1 receptors in the parts of your brain that regulate your emotions.
Some of the medical benefits of cannabis also happen when THC turns on the CB1 receptor. For example, THC helps with both the bodily sensations of pain and the unpleasant emotions that accompany chronic pain. It can also prevent and treat nausea and vomiting.
THC also binds to and activates CB2 receptors, which lowers immune system activity. Researchers believe this is another way THC may help lessen pain and inflammation. And THC may also be able to help treat autoimmune conditions, although more research is needed.
How does CBD interact with this system?
CBD doesn’t affect the ECS the same way that THC does. It doesn’t turn on CB1 receptors, it blocks them. This is why CBD doesn’t cause euphoria the way THC does. In fact, CBD may help lessen the euphoric effect of THC if they’re given together. And blocking CB1 receptors may be part of the way CBD lowers anxiety.
CBD does turn on CB2 receptors, which can reduce the activity of the immune system. This helps explain how CBD reduces inflammation.
Good to know: The cannabinoids found in cannabis also interact with receptors and systems in the body outside of the ECS. For example, CBD helps reduce seizures in certain people. But it doesn’t do this through cannabinoid receptors.
How do you know if there is something wrong with your endocannabinoid system?
Because the ECS was discovered so recently, we don’t fully understand how to recognize or diagnose problems with it.
For example, many people with autoimmune disorders, such as multiple sclerosis and rheumatoid arthritis, find symptom relief with cannabis. This suggests there may be a link between a poorly working ECS and autoimmune conditions. But more human studies are needed to confirm this.
Few healthcare providers specialize in the ECS, which is a new branch of medicine. Your provider may not have learned about the ECS (or cannabis as medicine) in their formal training. And there aren’t lab tests available to check for ECS-related problems yet. But hopefully this will change as more research is done.
How can you support your endocannabinoid system?
You can help support your ECS with certain lifestyle or dietary habits. Examples include:
Exercise: Exercise increases levels of endocannabinoids in the body. This may be how exercise helps lift your mood. Studies also suggest that endocannabinoids may be responsible for the “runner’s high” some people experience.
Healthy fats: Your body makes endocannabinoids from healthy fats. So adding olive oil or omega-3 fatty acids to your diet can help support a healthy ECS.
Probiotics: Animal studies show that probiotics may help regulate the ECS, especially when it comes to digestion and the gut.
Reduce stress: Your ECS helps you respond and adapt to stress. But chronic stress can “wear out” your ECS, making it less effective. Meditation, breathing exercises, and getting enough sleep are all steps you can take to lower stress levels and keep your ECS in tip-top shape.
Massage: Massaging the body may increase levels of endocannabinoids. The effect was larger with a specific type of medical movement known as osteopathic manipulative medicine.
Acupuncture: There’s some evidence showing that acupuncture’s effects may be related to activation of the ECS.
The bottom line
The endocannabinoid system, or ECS, is a group of messengers and binding sites that are located throughout the body. The ECS helps regulate your appetite, memory, and immune system. It also controls your sleep cycle and helps you manage stress. And it’s possible that other conditions, such as fibromyalgia, are linked to the ECS, too.
Messengers in the ECS are called cannabinoids. Your body makes its own cannabinoids, but they can also be made in a lab or found in plants, such as cannabis. Some of the medical and recreational effects of cannabis are due to how it interacts with the ECS.
You can help your ECS work its best by reducing stress, exercising regularly, and eating healthy fats. Probiotics, acupuncture, and massage may also help give your ECS a boost.
Why trust our experts?
If you or someone you know struggles with substance use, help is available. Call SAMHSA’s National Helpline at 1-800-662-HELP (4357) to learn about resources in your area.
Keep in mind that cannabis is legal in some states for recreational and/or medicinal use, but not in others. Cannabis is still illegal under federal law. Before you use cannabis products, find out the laws in your state.
References
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