Cannabis interacts with a system in the human body that regulates our immune defenses and we know that it can be helpful in treating auto-immune diseases. It is not necessarily as helpful when it comes to fending off viruses and other pathogens.
What Cannabis Does To Your Body
Chemicals in the cannabis plant called cannabinoids interact with the body’s endocannabinoid system. These chemicals mimic natural chemicals the body produces, which can cause different effects to functions like sleep, hunger, pain and mood.
An important role of the endocannabinoid system is to maintain homeostasis or balance of the immune system. There are some contradictions on how exactly this works, but it's generally considered to maintain a balance in the activity of the immune system — preventing it from causing overwhelming inflammatory responses.
For instance, cannabinoids are helpful in conditions where immune responses turn against the patient’s own body. Many autoimmune conditions, such as rheumatoid arthritis, multiple sclerosis and diabetes have been tied to dysregulation in the endocannabinoid system.
Still, in cases of infection from pathogens (and viruses), researchers warn that these immunosuppressive effects could be problematic — suppressing the body’s natural and needed immune responses.
Research on cannabis for immune health
Our scientific understanding of the endocannabinoid system suggests that cannabis could suppress important immune responses, thereby increasing our susceptibility to infectious diseases, but the research presents a more complicated overview.
Suppressing immune responses can be advantageous when dealing with some infections. Our bodies sometimes go into sepsis when dealing with a particular infection or disease — causing a systemic inflammatory response that can lead to death. Reducing this response could be live-saving.
Research on animals shows that stimulating endocannabinoid receptors with cannabinoids like those in cannabis can reduce infection-related inflammation, in some cases also reducing the overall death rate. Some studies also showed it improved recovery for infections like malaria.
In other animal experiments, reducing stimulation of these same receptors led to increased survival from infection. And in some experiments stimulating these receptors decreased immune response against infections like candida, legionella pneumophila, and influenza.
As you can see, animal studies present a somewhat conflicted picture. And human studies have been limited.
Potential benefits and harms
Despite all of the data from studies done on animals, early double-blind, placebo-controlled human studies found no immunological alterations observed with THC use. Later though, some immunosuppressive effects were found in the human research. In the same study, this effect reversed in two patients who had long term exposure to cannabis. So it’s possible that the long term effects of cannabis may differ from acute use when it comes to immune response.
Still, while researchers have found immune differences in humans from cannabis use, they haven’t confirmed that these alterations make cannabis users more susceptible to infection.
Cannabinoids show promise for treating viral infections (such as reducing sepsis), they can also pose risks like suppressing needed immune responses.
Researchers report that cannabinoids do have potential as treatments for infectious disease but say we need much more research to learn exactly how to use them in a way that ensures they are helping and not hurting our chances against an infection. Until more research is done, we really can’t say for sure.