Marijuana Increases Stress Resilience: Scientific Evidence
Regular marijuana users are significantly less nervous in stressful situations compared to those who are not familiar with it. This conclusion was reached by researchers from the Washington Institute, who conducted experiments on both cannabis enthusiasts and people who have rarely used it.
Recreational marijuana use is currently legalized in eight states and the District of Columbia. Last year, the nonprofit Drug Policy Alliance published a report on the impact of legalization on various sectors of the economy and public health. The main takeaway was that legalization did not cause any significant consequences—except for the end of arrests and trials for production, distribution, possession, etc., and new tax revenues flowing into state budgets.
However, for scientists, legalization changed a lot: it made possible research that was previously illegal, such as studies on the long-term effects of marijuana on the human body.
Where Marijuana Is Legal
In states marked light green, recreational marijuana use is legal; in those marked dark green, only medical use is allowed.
Short-Term and Long-Term Effects of THC
The short-term effects of tetrahydrocannabinol (THC, the active component of marijuana) have been well studied: in small doses, it calms, while in large doses it can cause anxiety, nervousness, and even paranoia. However, until now, science did not know how long-term use affects stress response, even though everyday experience suggests that regular marijuana users tend to be calmer than those who do not consume THC.
The Study: Marijuana and Stress Response
A group of psychologists, addiction specialists, and neurobiologists from the University of Washington conducted a study. They recruited 40 people who had used marijuana daily for at least a year, and 40 people who had smoked marijuana fewer than ten times in their lives. Both groups were placed in a stressful situation: they were asked to submerge their hand in very cold water and count backward from 2043 to 17, while being scolded for mistakes. In another group, participants put their hand in warm water and were not scolded for errors. Afterward, saliva samples were taken from all participants to measure cortisol—the stress hormone.
Results: Lower Cortisol in Regular Users
The level of cortisol (the stress hormone) in saliva was measured before and after the stress test. Blue bars represent data for non-users, while green bars show results for regular users. It turned out that experienced marijuana users produced significantly less cortisol than those who did not use it at all. The analysis matched the participants’ subjective assessments of their stress levels.
Researchers concluded that long-term, regular intake of THC does indeed make a person more stress-resistant. However, they note that this is not always a good thing. Stress is an important reaction to unfamiliar and dangerous stimuli; it allows us to mobilize resources and respond in any unclear situation. Life may be easier for calm and relaxed marijuana users—but what if there’s a crisis tomorrow?