Posted with permission from Newsweek

After a long and stressful day at work, some people enjoy coming home, kicking up their feet and savoring a full-bodied glass of red wine. Others might choose to loosen their collars with a stiff and sweet Brandy. And some adults would rather sit back and chill with a few puffs of a marijuana-packed joint.

Now that marijuana is legal for adults 21 and older in eight states, more people can freely indulge in the herb that’s long been considered the ultimate relaxer among stoners. Now, thanks to a few researchers from Washington State University, we may finally have an inkling of scientific evidence that cannabis reduces stress.

The study, published in the journal Psychopharmacology on Monday, found that regular marijuana users were significantly better at keeping their cool under stressful situations compared to those who did not use marijuana.

The study took 82 individuals and split them into two groups, including 40 self-identified chronic users and 42 people who had not used marijuana more than 10 times in their lives and not at all within the last year. All the participants experienced several physiological and psychosocial stressors. They were sober during the tests, but the marijuana users were allowed to consume the night before.

The experiment employed a method called the Maastricht Acute Stress Test, which exposes people to several situations know to elicit stress reactions in the body. For example, half the participants in each groups dunked a hand in a container of freezing cold water and left it there for 45 to 95 seconds. While their hand was submerged in the frigid water, they had to count backwards from 2,043 in intervals of 17. Every time they made a mistake, they were verbally reprimanded by a lab worker. And they had to watch their faces on a live video feed as they attempted the count.

The remaining participants within the two groups were given the easier task of sticking their hand in lukewarm water and count forward from 1 to 25. They weren't criticized or required to watch themselves performing the task.

The participants completed a stress-related questionnaire before and after each test. They also submitted saliva samples before and after the experiment, which researchers used to measure levels of cortisol, a stress-related hormone produced by the adrenal glands. According to the report, cortisol levels spiked dramatically among non-marijuana users who were given the cold water task compared to those who only had to stick their hand in lukewarm water. In contrast, chronic marijuana users in each stress-test group showed barely any difference in cortisol levels. 

In the findings, the researchers noted that daily marijuana users verbally reported feeling more stressed after performing the harder task, but they only showed “a significantly smaller increase in subjective stress rating” compared to non-users who had to perform the cold water challenge.

Carrie Cuttler, the study’s lead author and an assistant clinical professor in WSU’s psychology department, told Spokesman.com that the study couldn’t confirm the therapeutic effect of cannabis, but said the plant could modify stress response. 

“We’re not sure if it’s a good thing, a bad thing or potentially both,” she said, pointing out that weakening stress response in healthy people could have other negative impacts. “Cortisol helps to release energy stores and, more generally, just helps us to respond appropriately to threats in our environment.”

Next, Cuttler plans to analyze long-term cannabis use in lab rats to determine how residual THC   in users’ bloodstreams may have an effect on their response to stress. THC, or tetrahydrocannabinol, is the psychoactive ingredient in marijuana.

A separate Yahoo News and Marist College survey released in April found nearly 35 million adults in America used marijuana. Thirty-seven percent of these respondents turned to the recreational drug simply for relaxation.