What Is the Endocannabinoid System (ECS)? [Guide for Beginners]

The endocannabinoid system, often shortened to just ECS, is a powerful, complex and nearly ubiquitous in the nervous system that — among other things — enables your body to process cannabis. It’s because of the ECS and cannabinoid receptors dispersed throughout many brain regions and every organ in the body that your body can then make use of cannabis’s many compounds. So…thanks ECS!

This guide will provide a basic introduction to the endocannabinoid system. By the time you reach the end, you should have a solid understanding of fundamental concepts like:

  • What the ECS is.
  • Who has an ECS.
  • What the ECS does.
  • How the ECS works.
  • What happens when the ECS is outta whack.

Plus, we’ll cover how cannabinoids — like CBD and THC — engage with the ECS to yield their effects.

Endocannabinoid System (ECS) Overview

The endocannabinoid system (ECS), or endogenous cannabinoid system, was discovered in the 1990s by cannabis researchers. Though several decades have passed, experts still aren’t 100% clear on how — exactly — the ECS works or the extent of its influence on bodily functions and processes.

Research has revealed a whole lot, though! Let’s take a look. And, we promise to keep it high-level and interesting — no veering too far off into the weeds….

Who’s Got an ECS?

All animals — cows, horses, cats, dogs, other furry/feathery/scaly/slimy beings (except insects) — have an endocannabinoid system. That means YOU have one, too. And, it makes no difference whether or not you use cannabis. The ECS is still there inside your body, from head to toe.

That’s right. The ECS runs throughout the entire body. Not only can it be found from top to bottom, but inside to outside. The ECS is present in your tissues and organs, including your brain and skin.

What the ECS Does

Given the widespread existence of the ECS, it’s probably not a shocker that the ECS has its hand in a whole lot of your body’s workings. Evidence shows that this network helps modulate and control things (1,2) like:

  • Appetite
  • Body temperature
  • Digestion
  • Immune system
  • Inflammatory response
  • Learning
  • Memory
  • Mood and emotions
  • Pain
  • Reproduction and fertility
  • Sleep

As you can see, the endocannabinoid system touches on physical and mental health realms. It’s also understandable why researchers and doctors are eager to learn more about how the ECS operates and how we might leverage it to improve people’s well-being.

The overarching goal of the ECS is to facilitate your body reaching and maintaining homeostasis. Homeostasis is a biological term meaning stable equilibrium. In other words, your ECS is integral to your physical and chemical systems hovering around a nice balance point. When your body is in homeostasis, it’s more apt to function optimally.

ECS Building Blocks

The endocannabinoid system is made up of three parts: endocannabinoids, receptors, and enzymes. Let’s take a few moments to familiarize you with these pieces of the ECS.

Cannabinoids: Phytocannabinoids, Endocannabinoids & Synthetics

There are two classes of cannabinoids, naturally-occurring compounds that behave as neurotransmitters. Neurotransmitters are chemicals that send signals to receivers, which then relay that message on to other areas of the body.


Usually, when you see cannabinoid, it’s referring to phytocannabinoids. Phytocannabinoids, phyto meaning plant, are cannabinoids found in cannabis.

There are over 140 known cannabinoids.(3) Marijuana and hemp subspecies of cannabis both have many cannabinoids, though the exact ones they have and the proportions of each vary. Only cannabis has phytocannabinoids, though several other plants boast cannabinoid-like substances.(4)


Amazingly enough — your body produces cannabinoids of its own! This kind of cannabinoid is called an endocannabinoid (or sometimes an endogenous cannabinoid). Endo means within; endogenous means created within an organism.

Scientists have identified two major endocannabinoids to date:

  1. Anandamide (AEA). This endocannabinoid has many properties that are similar to THC. It acts upon the same receptors as THC and helps create the feelings of euphoria associated with THC.(5) AEA also plays a role in managing things like stress response, cognition, pain, inflammation, immune function, and fetal development.(6,7)
  2. 2-arachidonoylglyerol (2-AG). This endocannabinoid is found in abundance in the body’s central nervous system. Among the many things 2-AG is involved with are emotion, cognition, energy balance, pain sensation, and inflammation.(8)

Endocannabinoids are made on-demand — when your body needs them to facilitate some function. As such, researchers aren’t sure what a “normal” level of endocannabinoids is.(1)

Synthetic Cannabinoids

Man-made cannabinoids are a real thing. Created in a lab, they’re designed to mimic phytocannabinoids. (But only the “good” or beneficial aspects of the cannabinoid after which they are patterned.) Synthetic cannabinoids are used in pharmaceutical and other products.

CB1 & CB2 Receptors

Receptors, aka CB receptors, are a vital component of the ECS. There are two known endocannabinoid system receptors — CB1 and CB2. Each has its own particularities and purpose.(9,10,11,12)

  • CB1 receptors. These receptors are mostly found in the central nervous system — especially in various parts of the brain — nerve endings, testis, eyes, heart lining, and spleen. They’ve been observed to help instigate behavioral changes as well as combat metabolic syndrome and obesity. CB1s modulate the pace at which neurotransmitters like cannabinoids are released.
  • CB2 receptors. Situated mostly in the peripheral nervous, digestive, and immune systems, this receptor works to support the immune function and gut health and counteract inflammation. There’s also evidence suggesting that CB2s help protect the brain.

The structures and processes of the ECS sometimes vary across animals. For example, CB2 protein sequences are different in man, mouse, and mutt. However, the CB1 receptor is virtually the same in all mammals.(13)

ECS Enzymes

Last, but not least, are the ECS’s enzymes. Enzymes are proteins that your body produces to facilitate internal chemical reactions. In the case of the endocannabinoid system, enzymes operate like a demolition crew — breaking down waste (i.e., spent phyto-/endocannabinoid bits) and helping to usher it out of your system.

It seems like a Law of Twos ruling here. Because there are two primary enzymes involved with the ECS.

  • Fatty acid amide hydrolase. This enzyme disintegrates AEA after it’s completed its job.
  • Monoacylglycerol acid lipase. This enzyme typically deteriorates 2-AG when it’s done working its magic.
Cannabinoid receptors, named after cannabis, are found in nearly every organ of the human body. The discovery of the endocannabinoid system has opened a window into which bodily functions it plays a role in regulating.

How the Endocannabinoid System Works

Now that you know the basic pieces of the ECS and their roles, let’s look at how they combine to form a cohesive, high-performing system. Don’t worry, we’ll keep it simple!

ECS Operations, Step-by-Step

We’ll kick off with an analogy, to get a rough outline sketched in your mind.

Together, the three components of the ECS work kind of like a day on the trading floor of a 1980’s stock exchange. Investors call their brokers to buy or sell a security; brokers call the orders in to traders in the pit; traders execute the transactions and settle the books. There’s a trigger that starts the cycle, a message that conveys info, and a resulting action with an outcome.(14,15)

OK, back to real life. Here’s the generic ECS process in action:

  1. You consume cannabinoids, maybe orally in the form of CBD gummies or topically in the form of a CBD bath bomb.
  2. The cannabinoids work their way into your body via the skin, bloodstream, or digestive tract and begin to interact with the ECS receptors and endocannabinoids.
  3. The cannabinoids/endocannabinoids carry messages for the body to respond in a certain way. The receptors mediate and send the messages to the target destinations.
  4. These destinations receive the instructions contained in the messages. The systems and functions governing those areas of your body react accordingly and bring about some sort of effect.

Again, experts don’t have all the answers as to how this precisely works. They do know that, in the endocannabinoid system, cannabinoids and endocannabinoids correspond with ECS receptors. They’ve also determined that not all cannabinoids interact with the receptors in the same way.

For example, THC binds to receptors like an endocannabinoid. In fact, it can glom onto both CB1 and CB2.

CBD is more of a mystery. Instead of bonding with the receptors like THC does, it’s thought that CBD interacts with endocannabinoids. One idea is that this dance inhibits or changes the way that the endocannabinoids engage with the receptors. Another theory holds that CBD might be binding to an as-yet-unidentified CB receptor.

At any rate, the receptors are tasked with transmitting the cannabinoids’ signals throughout your system. Once the CB receptors get their marching orders, they instruct the body in how to respond. This is how the broad range of potential wellness effects — like alleviating pain, adjusting hormone production, easing anxiety, etc. — are created.

Helper Compounds — Phytocompounds

When you use cannabis products, you’re often also getting a dose of other helpful plant substances. Marijuana and hemp are loaded with constituents like additional cannabinoids (e.g., CBG, CBN, etc.), terpenes, flavonoids, and other phytochemicals.

Each one of these elements features health-promoting qualities that may be beneficial on their own. (That’s why plant-based medicine can be so powerful!) But they can also amp up the effects of cannabinoids — hello entourage effect! Some studies even indicate that terpenes may bind directly to CB1 and CB2 receptors or interact with the ECS in other ways.(16)

Cannabis Educators explain what the endocannabinoid system is and how cannabinoids and terpenes work in this GBL TV Cannabis 101 Watch Maria's Kitchen tutorial.

Endocannabinoid Deficiency Syndrome — What It Is & Why It Matters

This is a big, stand-alone topic all of its own — one we can’t dive too deeply into it here. However, it’s important to be aware of it.

ECS deficiency is also called clinical endocannabinoid deficiency, or CED. This is a condition or state in which the endocannabinoid system isn’t functioning at its best. The downstream effect of a suboptimally-functioning ECS is that the body can fall out of homeostasis. This might then lead to a panoply of issues — like the ones we’ve discussed above.

It’s still a working theory, but researchers are investigating CED’s possible causes, impacts on health and wellness, and potential for therapeutic treatments. However, there’s promising new information that suggests CED might be a critical factor in migraine, fibromyalgia, irritable bowel (IBS), and other treatment-resistant syndromes.(17)

Grow Your Know: The Endocannabinoid System Explained

The ECS is a complex network of endocannabinoids, receptors, and enzymes that exists throughout the bodies of almost all animals. Cannabinoids — like CBD and THC — engage with these three ECS components to bring about various effects in the body.

More and more scientific proof is showing that the ECS helps regulate or control many key systems and functions in the body. This is why everyone from researchers to doctors to you are looking to how we might leverage CBD to optimize our endocannabinoid systems and the work they do.

Endocannabinoid deficiency (CED) can occur when the ECS is thrown off kilter. CED may lead to various health or wellness concerns.

FAQs Buzzin’ Through the Hive

What is the endocannabinoid system (ECS)?

The ECS is a vast and complex network of endocannabinoids, enzymes, and receptors that exists throughout your body. All animals except insects have an endocannabinoid system.

What does the endocannabinoid system do?

Your ECS helps many of your body functions and systems do their jobs. It also is what makes it possible for your body to absorb and use the cannabinoids found in cannabis.

What is the endocannabinoid deficiency (CED)?

Clinical endocannabinoid deficiency (CED) occurs when your body’s ECS isn’t functioning properly or optimally. Because your ECS is a complex system that researchers are still working to fully understand, we aren’t sure why it can become dysfunctional or the extent to which deficiencies can impact one’s health.


  1. Raypole, C. (2019). A Simple Guide to the Endocannabinoid System. Healthline.
  2. Grinspoon, P. (2021). The endocannabinoid system: Essential and mysterious. Harvard Health.
  3. Sampson, PB. (2020). Phytocannabinoid Pharmacology: Medicinal Properties of Cannabis sativa Constituents Aside from the “Big Two.” Journal of Natural Products.
  4. Gertsch, J, et al. (2010). Phytocannabinoids beyond the Cannabis plant - do they exist? British Journal of Pharmacology.
  5. Scherma, M, et al. (2018). Brain activity of anandamide: a rewarding bliss? Acta Pharmacologica Sinica.
  6. Bird, E. (2020). Body’s natural cannabinoid may erase traumatic memories. Medical News Today. (2013).
  7. Annandamine Molecule - The bliss molecule. World of Molecules.
  8. Baggelaar, MP, et al. (2018). 2-Arachidonoylglycerol: A signaling lipid with manifold actions in the brain. Progress in Lipid Research.
  9. Kendall, DA, et al. (2017). Cannabinoid Receptors in the Central Nervous System: Their Signaling and Roles in Disease. Frontiers in Cellular Neuroscience.
  10. Mackie, K. (2006). Mechanisms of CB1 receptor signaling: endocannabinoid modulation of synaptic strength. International Journal of Obesity.
  11. Turcotte, C, et al. (2016). The CB2 receptor and its role as a regulator of inflammation. Cellular and Molecular Life Sciences.
  12. Dellwo, A. (2020). What Is the Endocannabinoid System? Verywell Health.
  13. Silver, RJ. (2019). The Endocannabinoid System of Animals. Animals.
  14. Chanda, D, et al. (2019). The endocannabinoid system: Overview of an emerging multi-faceted therapeutic target. Prostaglandins, Leukotrienes and Essential Fatty Acids.
  15. Zou, S, et al. (2018). Cannabinoid Receptors and the Endocannabinoid System: Signaling and Function in the Central Nervous System. International Journal of Molecular Sciences.
  16. Gonçalves, EC D, et al. (2020). Terpenoids, Cannabimimetic Ligands, beyond the Cannabis Plant. Molecules.
  17. Russo, EB. (2016). Clinical Endocannabinoid Deficiency Reconsidered: Current Research Supports the Theory in Migraine, Fibromyalgia, Irritable Bowel, and Other Treatment-Resistant Syndromes. Cannabis and Cannabinoid Research.
  18. Photo credit: pbs.org
Have something to say? Let's talk on social!

About the Author

GBL Staff Writer

Green Bee Life is your resource for accurate, transparent, and up-to-date content and products related to cannabis.

Related Posts

April 19, 2023
Be in the Know: How to Read a CBD Label like a Pro

CBD label literacy is a must for anyone who’s shopping for, buying, or consuming CBD oil products. But, understanding what’s included in CBD labeling can be confusing for the uninitiated. Learning how to read a CBD label just takes a little info and practice. We’re consolidating the basics of reading CBD oil product labels here […]

Read More
April 4, 2023
Does CBD Show Up on a Drug Test?

Does CBD show up on a drug test? The reply to this common question may surprise you. It’s a hard maybe. But you’ve come here looking for answers, and we’ll give you the full explanation. Whether or not you test positive on a drug screening after using hemp CBD depends on several key variables: Are […]

Read More
March 25, 2023
Certificate of Analysis (COA): All the Basics You Ought to Know

Ever wonder what's really in your cannabis products? You might be surprised by what's lurking in there. And — considering that you're putting THC and CBD products on or into your body — you probably don't want to be caught off guard. Enter the certificate of analysis, or COA. In this post, we'll analyze the […]

Read More
February 17, 2023
Making Sense of Cannabidiol Products: Formulations & Types of CBD

To say there are plenty of CBD product choices on the market today is perhaps a slight understatement. There are thousands of CBD brands, each offering a plethora of product formulations made with various types of CBD. Given the array before you, it can quickly get confusing or overwhelming. We’re going to resolve that here […]

Read More
1 2 3
Download your free guide New To CBD
Green Bee Life
*FDA Disclaimer: These statements and products have not been evaluated by the FDA and are not intended to diagnose, treat or cure any disease.

Copyright © 2024 Green Bee Life | Green Bee LLC, is a subsidiary of Green Life Media, Inc., a full service creative agency and production company.

logo for Maria's Kitchen GBL TV channel
logo for Green Eye for the Stoner Guy GBL TV channel
usercalendar-fullcrosschevron-down linkedin facebook pinterest youtube rss twitter instagram facebook-blank rss-blank linkedin-blank pinterest youtube twitter instagram