In 1563, Portuguese physician Garcia de Orta claimed cannabis could deliver users from “all worries and care.” It’s a hypothesis many can still get behind today, as numerous surveys show a significant portion of present-day cannabis consumers use the drug, in part, to reduce anxiety and stress.
But while many have long intuited the close relationship between stress and cannabis, our scientific understanding of this connection, and of cannabis in general, languished throughout the 20thcentury due to global prohibition, limiting research opportunities.
With the steady tide of legalization around the world, our understanding on this topic is evolving fast, like pretty much everything cannabis-related. For example, a 2009 study review established that people with stress-related anxiety disorders were indeed more likely to use cannabis, but whether this is due to the drug causing greater anxiety or its utility in treating preexisting symptoms remains to be seen.
To contextualize all the research-based revelations and new questions they raise about the effects of cannabis on stress, it’s important to start with the basics.
What Is Stress?
Like any negative emotion, stress exists for a well-established reason, which in this case is to help us identify and respond to potential threats or opportunities. Stress is the body’s reaction to danger, whether real or perceived.
It starts with a chemical reaction in the brain and manifests in a series of physical and emotional sensations like tightening muscles, heightened blood pressure and quickened heart rate. Together, these comprise our “fight-or-flight” response, a fearful and reactive state that’s useful for immediate life-threatening situations like outrunning a natural predator, but may become paralyzing when triggered by everyday concerns requiring more rational thought and creativity.
While stress may be manageable and beneficial in small doses, experiencing it chronically and in response to unwarranted situations can drain our physical and cognitive resources considerably, leading to all manner of short- and long-term health consequences ranging from emotional fatigue and low self-esteem (possibly constituting an anxiety disorder) to skin problems and cardiovascular disease.
How the effects of stress overlap with those of cannabis appears to come down to a part of the brain called the endocannabinoid system, which is crucial to numerous physiological processes such as fertility, appetite, mood, memory and rewards processing. It runs on a variety of neurochemicals called endocannabinoids traveling between cannabinoid receptors found throughout the brain, including in the amygdala’s central nucleus, which regulates anxiety.
While cannabis effectively delivers a stream of pleasure-inducing cannabinoids to our brains on cue, there’s reason to believe chronic stress contributes to the development of anxiety disorders by accomplishing just the opposite — reducing both our minds’ production of endocannabinoids and the responsiveness of receptors.
One process stress tends to inhibit is called Long-Term Potentiation (LTP), which enhances communication and synchronization between different neurons and plays an important part in learning and memory. In a 2013 study by the University of Haifa in Israel, lab rats who had endured chronic stress for two weeks were tested 30 days later and still showed impaired LTP between parts of the brain responsible for spatial memory and reinforcement learning.
This cognitive deficit was canceled out, however, in the experimental group of rats, who were treated daily after experiencing stress using a cannabinoid with the catchy name of WIN55,212-2. These results suggest even artificial stimulation of the cannabinoid system can measurably counteract the lingering impairments to learning and spatial awareness caused by chronic stress.
Apparently most useful for alleviating stress, however, is the natural endocannabinoid anandamide, which has also shown a proclivity for fighting certain cancers. In 2014, researchers at Vanderbilt University studied this relationship by first shocking their mice subjects’ feet for brief intervals to induce stress. The increased stress predicted a reduction of anandamide levels in the mice’s brains 24 hour after the shocks, but this was effectively reversed when researchers administered an inhibitor of fatty acid amide hydrolase (FAAH), responsible for breaking down anandamide.
These findings support the therapeutic potential of not just anandamide for treatment of stress-related disorders, but also of cannabis. Cannabidiol (CBD) — one of the main active ingredients in cannabis and primary source of its established health benefits — is another inhibitor of the FAAH enzyme, meaning it too can help preserve and restore the brain’s anandamide levels for greater resilience after cognitively taxing experiences.
This is how even the forgetfulness many stoners experience can come in handy. Smoking cannabis has been shown to facilitate the endocannabinoid system’s process of memory extinction by helping us forget painful and traumatic experiences, making it potentially well-suited for treating PTSD.
As promising as cannabis may be for alleviating stress-related disorders and reducing the harm caused by other, more addictive treatments, it’s by no means a one-size-fits-all cure.
For starters, frequent and chronic cannabis use can lead to diminishing returns by making our brain’s receptors accustomed to a steady diet of cannabinoids from an outside source. Thus, we create less natural cannabinoids to regulate anxiety and start depending on the drug for stress relief in a vicious, potentially addictive cycle.
There’s also less clarity on the relationship between anxiety and cannabis’ other major compound, tetrahydrocannabinol (THC), which was found in one study to reduce stress at low concentrations and amplify it at a more moderate dose. This could explain the heightened sense of fear and paranoia users will experience, especially when one is overindulging or new to cannabis.
Indicas and cannabis strains higher in CBD are assumed to be the safe bet for reducing anxiety, but this doesn’t account for the variability of other, less well-known endocannabinoid compounds, or terpenes, in cannabis. While this and other considerations of cannabis’ effects on stress are still waiting to be fully explored, there’s now little doubting the drug’s potential to change the way we think about and treat anxiety.