Numerous studies, journal articles, and media reports suggest that CBD and the endocannabinoid system play key roles in promoting homeostasis- but what exactly is homeostasis, and what does the endocannabinoid system have to do with it?
What is homeostasis?
Homeostasis is a term used to describe the process of maintaining internal balance in an ever-changing external environment. In humans, homeostasis refers to a plethora of individual yet interdependent processes that ultimately keep our bodies functioning properly.
The conditions within our bodies can fluctuate in response to a variety of external factors. Think about how things like temperature, stress, or even the food you eat can temporarily affect how your body works.
The heat on a particularly hot day, for example, might cause your blood pressure to drop and leave you feeling light-headed, fatigued, or nauseous. On the other hand, the stress of preparing for a work presentation or studying for an exam might cause your blood pressure to rise, leaving you feeling anxious or dealing with headaches and other physical symptoms.
These are just some examples of how the internal conditions of your body can fluctuate in response to the ever-changing conditions of the external environment. Luckily, your body has inbuilt response mechanisms to deal with these changes and get back to functioning properly as quickly as possible.
These different mechanisms all play important roles in helping our body achieve and maintain homeostasis. And while the individual homeostatic processes in your body vary, they are all made up of 3 essential components:
- Receptors responsible for sensing external changes.
- A Control Center that decides on how to respond to these changes.
- Effectors which carry out the relevant response.
To better understand how our body responds to external changes, let’s think about how it regulates our internal body temperature.
In this example, the control center is the hypothalamus, a part of the brain which helps our bodies detect changes in temperature and respond to them accordingly to maintain an optimal internal temperature.
In some ways, the hypothalamus works like a thermostat. Using receptors found both on the skin and internal structures within the body, the hypothalamus is able to sense any changes in temperature and respond to them accordingly. When temperatures rise, our body starts to promote heat loss in order to keep its internal temperature at around 37°C (98.6°F). When temperatures drop, on the other hand, our body reduces heat loss.
Thermoregulation is just 1 example of a homeostatic process that constantly takes place in our body. Body fluid composition, blood sugar, and blood pressure are some other processes involved in keeping our body operating at its best.
Homeostasis and the endocannabinoid system
The endocannabinoid system (or ECS) is a complex physiological system present in all mammals. Recent research has highlighted the complexity of the endocannabinoid system and suggests it is involved in managing various homeostatic processes.
There is a solid body of research exploring the role of the endocannabinoid system. Up until now, studies show that it is involved in managing pain, inflammation, immune response, appetite, metabolism, memory, mood and emotion, and much more.
The endocannabinoid system is made up of 3 main components:
1. Cannabinoid receptors (such as CB1 and CB2), which are found in various sites around the brain and body, as well as in specific cells of the immune system.
2. Endocannabinoids like anandamide and 2-AG which are produced in the brain and bind to either of the 2 cannabinoid receptors.
3. Metabolic enzymes that break up endocannabinoids after they’ve been used. The two main enzymes in the endocannabinoid system ar FAAH, which breaks down anandamide, and MAGL, which breaks down 2-AG
Unlike other molecules in the body, anandamide and 2-AG are synthesized and used when they’re needed, not produced and stored to be used later.
The growing body of research on the endocannabinoid system suggests that the endocannabinoid system switches into gear when it senses certain imbalances in the body, and then switches back off once order has been restored to the system.
Below we’ll look at some specific examples of how the endocannabinoid system can help regulate various bodily processes and promote homeostasis:
The endocannabinoid system regulates metabolism
By stimulating key receptors in areas like the digestive tract, the pancreas, liver, and even adipose tissue, the endocannabinoid system has been shown to directly affect a variety of metabolic processes.
Studies suggest, for example, that by stimulating receptors in the digestive tract, endocannabinoids can possibly influence digestion and nutrient uptake. Furthermore, research also shows that the endocannabinoid system can directly influence how nutrients are stored and transported around the body.
For example, research from 2016 showed that the endocannabinoid system is involved in a process known as “fat browning.” There are essentially 2 kinds of fat stores in your body; white fat, which is linked to higher risks of diabetes and heart disease, and brown fat, which can actually help burn energy and calories.
These results suggest that the endocannabinoid system may be a target for treating a variety of metabolic conditions, including obesity and diabetes. They also suggest that the ECS may help promote weight loss. Moreover, this research confirms that the endocannabinoid system has an important homeostatic role in regulating various metabolic processes.
The endocannabinoid system can regulate mood, emotion, and stress response
Besides its role in regulating metabolic processes, the endocannabinoid system has also been shown to be involved in managing emotions, mood, and response to external stress.
As we mentioned earlier, cannabis receptors (especially CB1) are present all throughout the body, especially in the brain (where CB1 receptors are among the most abundant G-protein-coupled receptors). Especially high concentrations of CB1 receptors are found in key areas of the brain involved in managing stress, emotion, mood, anxiety, and our response to fear.
This includes the:
- Prefrontal cortex
- Periaqueductal gray (PAG)
Animal-based studies have shown that by stimulating receptors in these various parts of the brain, the endocannabinoid system can help reduce stress, anxiety, and fear.
For example, a study from the 2008 European Journal Of Pharmacology showed that anandamide helped reduce anxiety in rats. Other studies have also shown that plant-based cannabinoids (especially THC) can actually produce anxiolytic effects.
Due to its involvement in managing fear and emotional responses, the endocannabinoid system has also become a possible target for treating patients suffering from depression, clinical anxiety, and even post-traumatic stress disorder.
The endocannabinoid system can affect immune function
Unlike CB1 receptors, CB2 receptors are most commonly found within immune cells. By either directly or indirectly stimulating these receptors, cannabinoids are believed to play a key role in promoting immune regulation.
Research suggests that the endocannabinoid system can help regulate immune homeostasis in the gut. Conditions like Crohn’s disease, for example, are characterized by an imbalance that causes the immune system to attack healthy tissue in the digestive tract. Studies show that cannabinoids can help reduce the chronic inflammation caused by these conditions and possibly restore order to the immune system.
A paper published in 2009 explored the role of endocannabinoids in regulating the immune system. Based on evidence that using cannabinoids or inhibitors of the enzymes of endocannabinoids (which essentially slow down the break down of compounds like anandamide and 2-AG) can suppress immune hyperactivity and help the body recover from immune-related injuries.
How can CBD promote homeostasis?
CBD is a natural compound derived from hemp. Unlike some other plant-derived cannabinoids, CBD doesn’t actually fit into any of the cannabinoid receptors in the body. However, it is still able to stimulate activity in the receptors without directly binding to them.
Instead of binding either to CB1 or CB2 receptors, CBD has 2 very unique effects on the body. First, it promotes the synthesis of 2-AG which, in turn, stimulates activity in the receptors. Secondly, studies show that CBD also inhibits the activity of FAAH, the enzyme responsible for breaking down anandamide.
CBD has been shown to bind another G-protein coupled receptor known as TRPV-1. This receptor is known to play an active role in regulating body temperature as well as pain and inflammation.
By interacting with TRPV-1 and provoking an increase in both anandamide and 2-AG, CBD indirectly promotes healthy endocannabinoid activity. And since the endocannabinoid system is directly involved in so many homeostatic processes, CBD may help give your system the boost it needs in order to continue functioning properly.