Understanding the link between cannabinoids and the digestive tract

While human beings have cultivated the cannabis plant for medicinal purposes for over 6,000 years, it was only in the late 1980s that we began to understand the complex system of chemical signals and receptors in the body known as the endocannabinoid system. Humans (and all mammals) produce cannabinoids (endocannabinoids) internally, while cannabis and hemp cultivars provide another type, known as phytocannabinoids such as THC and CBD.

Although cannabinoids have a broad spectrum of bio interactions across the body, some of the most interesting and potentially beneficial occur in the gut. As the importance of digestive health in overall well-being has come into sharp focus in recent years, this is an excellent time to take a close look at the relationship between cannabinoids and the digestive tract, and the role that these natural compounds may have in aiding digestive health. As the UK faces a rise in inflammatory bowel conditions, we will also look at the role of cannabinoids in mitigating the effects of gut inflammation.

What are cannabinoids?

In the broadest of terms, cannabinoids are simply any compounds that bind to cannabinoid receptors. Cannabinoid receptors are one part of the endocannabinoid system, or ECS, which is the largest regulatory system in the human body.

Let's break down the ECS before we move on.

The ECS is the most extensive network of receptors in the body and permeates all 11 of the body’s central physiological systems. It is made up of two types of receptors, CB1 and CB2, as well as our own endocannabinoids (anandamide and 2-arachidonoylglycerol), and the enzymes that synthesise and then break down cannabinoids.

CB1 receptors are primarily found in the brain, while CB2 receptors are more abundant in our peripheral organs, particularly in the gastrointestinal (GI) tract. When a cannabinoid binds to either type of receptor, it can trigger a cascade of distinct functions within the body that can influence many of the body’s most essential functions. This includes appetite and sleep to memory, mood, reproduction and, crucially, the body’s inflammatory response to environmental stimuli, injuries, and infections. It even plays a role in immune function and emotions.

To date, researchers have successfully isolated 113 phytocannabinoids from cannabis and hemp strains. The two most prominent are cannabidiol (CBD) and tetrahydrocannabinol (THC). THC is the intoxicating compound that gives the cannabis plant its psychoactive effects. CBD is totally non-intoxicating but still interacts with the ECS (and other bodily systems) to offer potential wellness and therapeutic benefits.

While most CB1 receptors are located within the brain and central nervous system, and CB2 receptors are found in the cells of the immune system, the gastrointestinal system actually contains both. There is a growing body of research to suggest that cannabinoids affect the digestive tract in ways that may result in positive health outcomes.

How do cannabinoids affect digestion?

Cannabinoid receptors within the gut are bountiful and there is evidence to suggest that they could help to improve digestive health. Moreover, it is speculated that a deficiency in clinical endocannabinoids (where the body does not produce enough of its own cannabinoids or receptors) could be a factor in cases of irritable bowel syndrome, fibromyalgia, and gut disorders like Crohn’s, ulcerative colitis, and inflammatory bowel disease (IBD). There is even evidence to suggest that cannabinoids can play a role in counteracting the appetite loss and muscle wastage that comes with many forms of cancer and conventional cancer treatment options.

Cannabinoids, most notably CBD, have been shown to offer anti-inflammatory properties that may play a role in maintaining gut health and digestive function. Before we take a look at how cannabinoids can mitigate the effects of inflammatory bowel conditions, let's review the scientific literature regarding some of the more general ways in which cannabinoids affect the digestive system.

Cannabinoids and intestinal motility

As this review in the Journal of Gastroenterology states, the endocannabinoid system plays a significant role in the homeostasis of the digestive system.

One significant process in this is the motility and peristalsis of the digestive system – the stretching and contracting of the muscles in the digestive tract that move food through the body’s digestive system. When gut motility is increased, food passes through the digestive system too quickly resulting in bowel irritation, bloating, and loose stools.

A study by the British Journal of Pharmacology concurs that cannabinoids can assist in slowing intestinal motility and preventing the stomach from being emptied too early. It concludes "Activation of cannabinoid receptors is beneficial for gut discomfort and pain related to dysmotility and visceral perception".

Cannabinoids and gastric acid secretions

There is also evidence to suggest that cannabinoids assist in maintaining the pH levels of the digestive tract and managing the secretions of gastric acid. As well as inhibiting the secretion of gastric acids, cannabinoids can also aid the secretion of protective mucus that prevents seepage and diffusion of gastric acids that may result in irritation.

Cannabinoids and the gut microbiome

The gut is home to a complex microbiome of bacteria and flora that not only regulate digestive health but have been linked to immune function, heart health, and mental health.

The balance of the gut microbiome is a significant yet often overlooked variable in the onset of not only gastrointestinal conditions but also neurodegenerative conditions. When ratios of different gut phyla are out of kilter, it can increase the risk of obesity and colorectal cancer.

Several studies have linked cannabinoids to achieving a gut microbiome balance that metabolises energy more efficiently and improves glucose tolerance, reducing the risk of obesity and associated conditions.

While research into the role of cannabinoids in promoting digestive health is still relatively new, existing studies paint a promising picture of the applications of cannabis and cannabinoids for the treatment and management of numerous digestive conditions.

Does cannabis help to alleviate digestive disorders?

Inflammatory digestive disorders are on the rise in the UK and globally. Researchers from the University of Liverpool have identified a significant increase in inflammatory bowel conditions in the UK including almost 70,000 cases of microscopic colitis – a bowel condition that is often undiagnosed and untreated. Irritable bowel syndrome (IBS) is another substantial health concern for British patients, affecting around 12% of the population.

The good news is that there is evidence to suggest that cannabinoids like CBD and THC may be effective in mitigating these conditions.

Researchers from the University of Bath, in partnership with the University of Massachusetts Medical School, ascertained that inflammation of the gut is regulated by two processes – the immune response within the gut (which can destroy harmful pathogens but also attack friendly cells), and a newly-discovered second process whereby molecules transported into the intestinal cavity through the gut lining that effectively sends a signal to the body to turn off its inflammatory response. The research indicates that cannabinoids are integral to this process.

By suppressing inflammation, aiding healing, and reducing the permeability of the gut, cannabinoids have been shown to aid in the treatment of inflammatory bowel diseases such as ulcerative colitis and Crohn’s disease.

These conditions can be triggered or exacerbated by chronic stress and anxiety, which is another condition for which cannabinoids can be effective. CBD and THC have both been linked to reduced stress, binding with receptors in the brain and mitigating the effects of stress on the digestive system and other bodily processes.

However, studies warn that while these cannabinoids may bring short-term relief, proper balance between the two compounds is necessary to prevent a risk of exacerbated baseline symptoms over time.

What is cannabinoid hyperemesis syndrome and how can I avoid it?

Much of the research investigating the role of cannabinoids in digestive function is positive and encouraging. However, long-term cannabis administration also carries a mild risk of some more adverse digestive health outcomes. One of these is cannabinoid hyperemesis syndrome (CHS).

This is an exceedingly rare condition that occurs in only a small subsection of regular and long-term medical cannabis patients. It is typically characterised by bouts of nausea and recurrent vomiting. It is not yet completely clear what causes CHS, although the most likely causes are overstimulation of the endocannabinoid system and genetic predispositions.

Many patients suffering from this condition also experience abdominal pain, loss of appetite, and weight loss. If left untreated, CHS can result in complications including muscle spasms, seizures, kidney failure, and cardiac arrhythmia.

Symptoms almost always abate when patients stop taking cannabis. However, doctors may treat symptoms with a combination of painkillers, antipsychotic medications such as olanzapine to combat nausea, and intravenous hydration if severe bouts of vomiting have left the patient severely dehydrated.

How to reduce CHS risk

The risk of CHS can be reduced by using cannabis only for medicinal purposes and paying close attention to dosage and frequency of consumption. While CBD is likely one of the cannabinoids that contribute to CHS, it is also a compound to which the body is very tolerant.

Therefore, taking a full-spectrum CBD oil or tincture to treat digestive disorders may be an effective way to further reduce the risk of CHS while also enjoying the relief that cannabinoids can provide.

As research into CHS continues, it is important to remember that the risk of experiencing this syndrome remains low in comparison to the potential benefits of medical cannabis for digestive disorders.

Final thoughts

As we can see, there is a clear and scientifically established link between cannabinoids and the healthy, effective function of the digestive tract. However, it is important for medical cannabis patients to find the right strain and dosage schedule for their individual needs.

Before making any changes to your current treatment plan, it is essential to seek the guidance and advice of a healthcare professional who has experience prescribing medical cannabis for your particular condition. At Releaf, our team of experienced and dedicated medical cannabis experts are on hand to answer any questions you may have about starting your medical cannabis journey.

We understand the importance of medical cannabis in treating various medical conditions. With our tailored monthly packages, specialist consultations for medical cannabis, and a unique medical cannabis card for protection, you can access the treatment you need without worrying about the stigma.