Many people have seen success with cannabis therapy, one big question still looms: What does marijuana do to the immune system?
Marijuana has quickly become something of a health trend. In states where people can access medical marijuana, it's often used as a remedy for a whole host of conditions. Multiple forms of cannabis exist and can be used to relieve a gamut of symptoms. One person could use infused coconut oil to treat a rash, where another might use it to soothe arthritis-related inflammation.
Edibles are often a favorite for patients suffering from chronic, terminal diseases, and smoking and vaping show no signs of losing popularity yet.
Understanding the Immune System
Obviously, the immune system is an extremely complex network of cells and organs, working in concert to protect your body from potentially ravaging invaders. An interaction between marijuana and the immune system could affect any number of processes that continually take place in within that system.
It helps to be familiar with some basic terms and processes of the immune system before we take a deep dive into the science-heavy side of things, so let's cover the bare basics.
- White Blood Cells: White blood cells are your immune system's first line of defense against intruders. They circulate with your blood, on the lookout for pathogens. There are a few different types of critical white blood cells. Lymphocytes are responsible for recording previous intruders so your immune system recognizes them if they return. B lymphocytes alert T lymphocytes (your T cells) to come destroy cells that have been compromised.
- Cytokines: These cells are known as "immunomodulating agents" that act on nearby cells to different ends. Some cytokines promote inflammation, and some are anti-inflammatory, making them a helpful measure of immune competence. Cytokines may also play a direct role in pathologic pain, since they can directly activate certain sensory neurons.
- Immune Response: An immune response happens when B lymphocytes see an intruder. Other white blood cells then work together to coordinate and carry out attacks on these other cells in order to destroy viruses, bacteria, and infected cells. This process is where cytokines call for inflammation, to help separate infected or damaged parts of the body from the healthy parts.
Cannabis and Inflammation
Since inflammation is such a key aspect of your body's immune response, it makes sense to start with that aspect of marijuana and the immune system. Since inflammation occurs as a protective measure in the body, it's a double-edged sword.
Too little inflammation in response to a bacteria or virus means that the illness is able to spread faster and get you even sicker, even quicker. Too much inflammation means significant pain.
We know that cannabis can help with inflammation. Certain cannabinoids act more acutely against inflammation, namely CBD and beta-caryophyllene. These compounds bind with the CB2 receptors in the brain, allowing them to down-regulate (or decrease) your inflammation response. For certain illnesses, this can be a crucial step in lessening pain.
Cannabis and Autoimmune Diseases
Normally, the immune system mounts a response to invading cells or damaged cells. But with an autoimmune disease, your body essentially becomes confused and starts attacking your own healthy cells. Rheumatoid arthritis (RA) is a prime example of an autoimmune disease. This condition causes your immune system to attack the linings of your joints, leading to painful and ravaging inflammation that can spread through the whole body.
Since cannabis can suppress immune response by working directly with the endocannabinoid system, it can work wonders in those with autoimmune disorders. But what about diseases that are marked by immune suppression?
Cannabis and HIV
If marijuana acts to suppress the immune system in terms of inflammation, that means it's dangerous for people suffering from a compromised system due to HIV, right? It's not quite that simple. A few studies have been done on marijuana and the immune system in people with these diseases. The results are frustratingly inconclusive, but also intriguing.
HIV involves a virus that takes over the immune system and suppresses its ability to ward off infections. The immunosuppression caused by HIV makes sufferers more vulnerable to illness, and therefore they're more likely to die prematurely.
In 2015, one study revealed that HIV-positive participants that consumed marijuana had lower average viral loads than non-users. The participants who reported cannabis use also had significantly higher levels of CD4 cells (a type of T-cell that naturally kills the HIV virus). This supports the findings from a 2003 study of 62 patients, which reported a 20% increase in T-cells in people who consumed marijuana.
Another study was conducted in 2016, and although it had a much larger sample size at 955 HIV patients, it failed to find any positive or negative association between immune system functionality and the consumption of marijuana.
Cannabis and Cancer
Cancer is the result of cells failing to recognize the triggers that normally tell them to self-destruct. With nothing to stop them, these cells will grow and multiply out of control, The function that results in the destruction of diseased cells is called "apoptosis," often referred to as cell suicide.
If your immune system isn't functioning properly, you may end up with too much apoptosis, or too little.
In multiple instances, cannabinoids have shown an ability to trigger apoptosis in cancer cells. Some research credits cannabinoids as an avenue worth exploring for cancer treatment, as they can "provide a targeted treatment of cancer." They do so by actively modulating the endocannabinoid system to make your body's environment more hostile to cancer cells. In fact, this study suggests complications of cancer are potentially aided by abnormalities in the endocannabinoid system.
Such abnormalities "promote cancer by fostering physiological conditions that allow cancer cells to proliferate and migrate." This study does admit that while modeling systems and mice models show cannabinoids to be effective at inducing apoptosis, there is a lack of research in actual humans.
Rounding Up The Evidence
In an attempt to draw conclusions about marijuana and the immune system, a group of researchers reviewed all the available research on the subject in 2017. The review, entitled The Health Effects of Cannabis and Cannabinoids, looks at cannabis from many angles. Chapter 8 is all about immunity, and despite the multiple entries of previous research, the reviewers were unable to draw any overarching conclusions on marijuana and the immune system.
Because every available study focuses on one aspect of the intersection between cannabis and immune function, there are many gaps in the literature. As it stands, "There is insufficient evidence to support or refute a statistical association between cannabis or cannabinoid use and adverse effects on immune status."
There is, however, "limited evidence" of marijuana's ability to act as an anti-inflammatory.
For most people, this news doesn't mean much. If you have a healthy immune system, the minor suppression that cannabis can cause isn't likely to do much damage. And if you're suffering from an autoimmune disease that causes your immune system to be hypervigilant against your own cells, marijuana may be just what the doctor ordered.
Even cancer, which is known to decrease the efficacy of immune response, can benefit from the potential apoptosis increase cannabis brings. The clinical evidence on marijuana and the immune system may be inconclusive, but the sheer number of positive anecdotes surrounding cannabis and disease are sure to result in more research in the future.