Cannabinoids have been the subject of many research studies over the past few decades. With the potential to help a whole host of medical conditions, and a low risk of side effects, they have been hailed by some as a new wonder drug. For others, using marijuana is a more recreational affair, and its mind-altering properties are as popular now as they have ever been.
As scientists seek to understand the impact of cannabinoids on the body, more and more evidence of their potential benefits is becoming clear. These findings have led people’s attitudes towards cannabis to change slowly, both within the medical profession and the population at large. With cannabis laws being relaxed in many places, and medical marijuana becoming more widely available, it is now even more important to understand the chemistry of cannabinoids and their effects on the body.
What are Cannabinoids?
‘Cannabinoids’ is the name given to a large group of chemical compounds which work similarly within the body. There are two types of cannabinoids, endocannabinoids and phytocannabinoids.
Endocannabinoids are made inside the body. They are synthesized by enzymes as and when their functions are required. Phytocannabinoids, on the other hand, are compounds found in plants such as Cannabis sativa. These phytocannabinoids can enter the bloodstream via the respiratory system when smoked or the digestive system when eaten. Once inside the body, they work in a similar way to endocannabinoids.
The two most well-researched endocannabinoids are anandamide (AEA) and 2-arachidonoylglycerol (2-AG), although there are several others. Phytocannabinoids are even more varied, and there are around 100 naturally occurring cannabinoids found in the cannabis plant. The most well-known of these are Δ9-tetrahydrocannabinol (THC) and cannabidiol (CBD).
The Effects of Cannabinoids on the Body
Your body’s cells are covered with what are known as receptors. These receptors are shaped to fit a specific molecule, much like a lock is shaped to fit a specific key. When a molecule binds with a receptor, it causes a reaction within the cell, which leads to a physiological response. These receptors can either be activated or blocked, and most of your body’s vital processes are managed in this way. Your nervous, immune, digestive, and reproductive systems all rely on receptors to function as they should.
Endocannabinoids are designed to fit receptors known as CB1 and CB2 receptors. The majority of CB1 receptors are found in the brain and central nervous system, whereas CB2 receptors are mainly found in peripheral tissue and the immune system. AEA and 2-AG bind with these receptors to control a wide range of biological functions including appetite, immunity, fertility, and regulation of the nervous system. These endocannabinoids, cannabinoid receptors, and various enzymes all make up what is known as the endocannabinoid system.
A major function of the endocannabinoid system is helping your body to maintain homeostasis, a state of internal equilibrium which is vital to good health. If this system becomes dysfunctional, it can result in problems such as inflammation, pain, epilepsy, impaired memory, addiction, obesity, cardiovascular disease, and even some forms of cancer.
The phytocannabinoids THC and CBD also have the ability to bind to CB1 and CB2 receptors and cause a range of different effects throughout your body.
THC affects both types of cannabinoid receptors, although it affects CB1 receptors more readily. When THC binds to these receptors, it simultaneously activates and blocks them. This action appears to influence the release of neurotransmitters, with a mixed stimulatory and inhibitory effect.
Neurotransmitters are chemicals which are responsible for controlling your mood, emotions, and mental function among other things. By influencing these chemicals and the way they interact with nerve cells, THC has a number of effects on your body and mind, including the psychoactive “high” which is associated with cannabis use.
CBD binds to CB1 and CB2 receptor less readily than THC. However, it still has many dramatic effects on the body. Even at low doses, CBD has an inhibitory effect at CB1 receptors and balances the action of THC at these sites. At the CB2 receptors, it influences the immune system and appears to have potent anti-inflammatory effects.
The Effects of Cannabinoids on Inflammation and Pain
Inflammation is a natural response by your body to injury or infection. When your immune system senses a threat of this type, it triggers a chain reaction, increasing blood flow to the area and transporting an army of white blood cells which are specifically designed to destroy invading bacteria and viruses.
The downside of this response is that the area becomes red, hot, swollen, and tender. These are the classic signs of inflammation, and you will have experienced them if you have ever strained a muscle, cut yourself, or had the flu.
Inflammation is a useful and healthy process, and in most cases will subside after a few days. However, in some conditions such as arthritis, inflammation never goes away and the sufferer is left with symptoms such as chronic pain and stiffness. Chronic inflammation has also been linked with many serious diseases including heart disease, strokes and diabetes.
CB2 receptors located in the immune system are thought to play an important role in immune function and the inflammatory process. These receptors’ ability to manage inflammation, combined with the action of CB1 receptors in the central nervous system, is the reason why cannabinoids are considered such a useful treatment for inflammatory conditions such as chronic pain.
The Antioxidant Effects of Cannabinoids
Cannabinoids are also regularly reported to have an antioxidant effect. We often hear about certain foods or supplements being high in antioxidants, but what does that really mean?
To understand antioxidants, we need to look back to the immune system and the inflammatory process once again. When white blood cells are channeled to an infected area, they deal with unwelcome visitors in a variety of ways. Some types of white blood cells are designed to consume bacteria and viruses, breaking them down much like your stomach would digest a meal. Other types of white blood cells work by releasing chemicals called reactive oxygen species (ROS), more commonly known as free radicals. These are highly unstable molecules which are designed to react with foreign bodies and damaged tissue and destroy them.
Like inflammation, this should be a temporary, targeted process. However, it is possible for ROS to get out of control and begin attacking healthy cells and tissues. This harmful process is known as oxidative stress and often occurs in the presence of environmental toxins. Like chronic inflammation, oxidative stress has been linked with many serious diseases, and that is where antioxidants come in.
Antioxidants are chemicals which react with ROS to make them more stable and stop the chain reaction of oxidative stress. Cannabinoids have been found to do this and more. As well as reducing the harmful effects of ROS, they appear to act as a powerful neuroprotectant agent, preventing nerve cells from being damaged. What is even more interesting is that they seem to do this completely independently from the CB1 or CB2 receptors, meaning that cannabinoids have multiple mechanisms of action within the body.
The Medicinal Use of Cannabinoids
With such potent anti-inflammatory and antioxidant effects, it should come as no surprise that cannabinoids also have varied and far-reaching medicinal benefits.
Research has shown that cannabinoids may be helpful in the treatment of many different conditions including chronic pain, chemotherapy-induced nausea and vomiting, spasticity due to multiple sclerosis, anorexia and weight loss, epilepsy, anxiety, depression, dementia, and more.
The advantage of cannabinoids over many conventional medicines is that they are naturally occurring and carry a low risk of adverse effects. Most of the side effects of cannabinoids can be attributed to the psychoactive effects of THC, including drowsiness, euphoria, paranoia, and increased appetite. CBD is far less likely to cause side effects, although it may interact with other medications taken at the same time.
The use of cannabis and cannabinoids as medicine is still in its infancy, but these compounds do show great promise and are likely to become more widely used in the near future.
As well utilizing naturally occurring cannabinoids from cannabis, scientists have also developed several synthetic cannabinoids which work in a similar way. Drugs like nabilone and dronabinol may be more acceptable to some people than marijuana, which still has some stigma attached to it. However, cannabis contains a whole range of chemicals which work together, synergistically, on the body. Therefore, isolating and synthesizing one particular cannabinoid may be less effective than using the plant itself.
Final Thoughts on the Chemistry of Cannabinoids on the Human Body
There are many different cannabinoids. Some are produced naturally by the human body, and others are found in the Cannabis sativa plant. These chemicals have a wide range of effects on the body, ranging from the psychoactive properties of THC to the anti-inflammatory actions of CBD.
Cannabinoids play a crucial role in maintaining the balance of our biological systems and have a great deal of potential as a natural medicine. Cannabinoids, especially THC, may cause some unwanted effects within the body. However, they are generally considered safe and are well tolerated in most people.
For more information about the chemistry of cannabinoids and how they may affect you personally, talk to your physician or healthcare provider.