The endocabbinoid system (ECS) is comprised of receptors, neurotransmitters, and metabolic enzymes that help maintain homeostasis. The ECS has beneficial effects on digestion and immune function. Cannabidiol (CBD) activates the ECS to reduce intestinal permeability, regulate gut bacteria and reduce inflammation. The nervous system and gut-brain axis are equally responsive. This explains how CBD can help depression, anxiety and post-traumatic stress disorder (PTSD). It is also used to treat neurological conditions like epilepsy and Parkinson’s.
How does CBD work?
CBD is the non-psychoactive component of the cannabis plant. It activates the endocannabinoid receptors: CB1 and CB2. The nervous system is primarily affected by CB1. These receptors are also found in our glands, adipose tissue and organs. The immune system is primarily affected by CB2.
The Gut-Brain Axis
The gut has more CB2 receptors but because it is considered our second brain there is also substantial CB1 activity. Our digestive system is a bundle of nerves. Nutrient absorption and cellular hydration can be improved by activating the endocabbinoid system. Sleep is critical for digestion and CBD supports deep sleep. But that’s just the beginning.
The gut-brain axis is the bidirectional interplay between the gut microbiota and the nervous system. Our microbiome can impact behavior and cognition and the central nervous system can influence our microbiota composition. This axis helps explain the inflammatory cytokine model of depression which is now widely accepted.
The endocannabinoid system supports gut motility, hunger signaling, inflammation and the gut lining. CBD helps recruit immune cells to suppress pro-inflammatory cytokines. The anti-inflammatory effect of cannabinoids in the gastrointestinal system has been researched in regards to both inflammatory bowel disease and irritable bowel syndrome. Epigenetics play a role too. Psychological stress can change how CB1 expresses. Pain in the abdomen when we are stressed as well as early life trauma leading to IBS can both be explained by this.
Anxiety & Post-Traumatic Stress Disorder
Stress and anxiety are regulated by the endocabbinoid system. In animal studies chronic, unpredictable stress was reduced and anxiety lessened. Both CBD and serotonin receptors were involved. Another study involving humans with generalized social anxiety disorder who were not receiving medication benefited from 600 mg of cannabidiol. Cognitive impairment and anxiety levels were reduced.
Research on post-traumatic stress disorder using imaging indicates the the EDS system is underactive. Cannabinoids may improve PTSD symptoms such as sleep quality and hyperarousal. In fact, a synthetic cannabinoid called Nabilone reduced nightmares in a small group of Canadian military personnel with PTSD.
Suppressing CB1 receptors results in symptoms associated with depression. Decreased appetite, increased anxiety, arousal, and wakefulness increased when endocabbinoid activity was suppressed. In fact, some antidepressant medications work by increasing EDS activity.
CBD protects against the effects of stress and depression. It lowers the autonomic and behavioral effects of depression while improving neurogenesis. As I mentioned serotonin works with the EDS. I have a tool for assessing serotonin that you can access here.