The Endocannabinoid System

The endocannabinoid system (ECS) helps to provide and improve homeostasis – a state of balance and stability – within living organisms. While this system is a natural feature of humans and other mammals, its structure is complex. Through a “lock-and-key” signaling system, the ECS impacts various physiological systems by orchestrating communication among the body’s enzymes, receptors and cannabinoids.

What Constitutes a Cannabinoid?

The term “cannabinoids” refers to organic chemical compounds present in Cannabis. Technically, a plant-based cannabinoid is referred to as a phytocannabinoid. There are also lab-manufactured, synthetic cannabinoids. Few people realize that the human body produces cannabinoids, too; these are known as endocannabinoids.

Making Sense of Signals and Structure

Basic ECS structure includes three essential elements: receptors, lipids and enzymes. Following is a brief description of each, which helps to illustrate how they work together:


Researchers at the St. Louis University School of Medicine discovered the cannabinoid receptor in 1988. Today we know of two types of cannabinoid receptors: CB1 and CB2. (Both are also G protein-coupled receptors.) CB1 receptors are found mainly in the brain and central nervous system, while CB2 receptors are located in peripheral organs.


Two lipids produced by the body serve as ligands (bonding agents) for the cannabinoid receptors: anandamide and 2-arachidonoylglycerol (2-AG). Both are endocannabinoids.


Enzymes (including monoacylglycerol lipase and fatty acid amide hydrolase) create endocannabinoids.

Receptors at Work: Balancing Acts

CB1 and CB2 receptors create chemical signals to produce and dissolve metabolic enzymes. In turn, the enzymes influence a variety of physical and psychological conditions, including inflammation, appetite, pain, metabolism, muscle control, sleep, intra-ocular pressure, stress response, mood and weight loss, among others. CB1 and CB2 differ in their functions and balance points.


  • Research indicates that a dominant CB1 decreases nausea, vomiting and pain.
  • Anecdotal reference also points to reduced anxiety, paranoia and stress, as well as enhanced immunotherapy associated with certain cancers.
  • Over-active CB1 receptors may lead to increased appetite, and therefore the potential for obesity, muscular insulin resistance and increased glucose intake.


  • Predominant CB2 receptors are associated with decreased tissue injury and inflammation.
  • Other reported benefits include improved insulin signaling, better metabolic health and energy balance.
  • Over-activation of CB2 receptors may result in decreased function of the immune system and impaired wound healing.

Bottom Line: More Therapeutic Options for Patients and Practitioners

Since its discovery about 30 years ago, the ECS has opened new vistas of beneficial therapeutic options for patients and physicians alike:

  • Positive effects, physically and emotionally
    For example, the ECS can help diminish (and sometimes known to eradicate) nausea associated with some cancer therapies. Similarly, the ECS can increase or decrease appetite, just as it can alter mood – from peaceful and pensive to active and imaginative.
  • Maintaining equilibrium and stability
    Most importantly, the ECS promotes homeostasis – the body’s natural tendency to maintain internal equilibrium and stability, even under adverse conditions of illness, pain and emotional duress.
  • A foundation for well-being
    Consequently, the ECS has earned recognition as a central component of mental and physical well-being. Small wonder that both traditional and homeopathic medical practitioners continue to research the ECS and the wealth of therapeutic value it holds.

NORML: Introduction to the Endocannabinoid System

National Institutes of Health: The Endocannabinoid System as an Emerging Target of Pharmacotherapy