Washington State University researchers have found evidence supporting an already popular theory: that regular cannabis users stay more relaxed in stressful situations.

A study published recently in the journal Psychopharmacology found that daily – or “chronic” – cannabis users were significantly calmer than nonusers when subjected to a barrage of physiological and psychosocial stressors – even though all of the participants were sober on the day of testing.

“This study is actually quite novel and new and different from those that have been previously conducted,” said Carrie Cuttler, an assistant clinical professor in WSU’s psychology department and the lead author of the study.

Cuttler said only a small amount of research has examined the relationship between cannabis use and stress, and much of it relies on self-reported data. As might be expected, most survey respondents list “relaxation” or “stress relief” among the top reasons they use pot on a regular basis, she said.

Other studies have measured the effects of individual doses of THC, the active chemical compound in pot. Researchers in Chicago, for example, recently found that low doses of THC can relieve stress, while slightly higher doses – enough to produce a mild high – actually increase anxiety.

Cuttler and her colleagues asked a different question: Would a heavy cannabis user still experience stress-relieving or stress-inducing effects after a high wears off?

“There have been studies before that looked at whether people were high or not high,” she said, “but nobody’s looked at sober cannabis users.”

So the researchers recruited two groups of people: 40 who self-identified as chronic users and 42 nonusers. The first group had used cannabis daily or almost daily for at least a year. The second group had used it 10 or fewer times in their life and not at all during the previous year.

All of the participants were required to abstain from using cannabis on the day of testing, although they could use it the night before. The experiment involved a procedure called the Maastricht Acute Stress Test, or MAST.

Half of each group of participants were told to dunk a hand in a container of frigid water and leave it there for 45 to 90 seconds. At the same time, they were told to count backward from 2,043 in intervals of 17, while being chided by lab workers each time they made a mistake. Compounding the stressors, they also had to watch their own faces on a live video feed as they attempted to perform the count.

The other half of the participants – the control group – had a much simpler task. Their nonstressful scenario involved dipping a hand in lukewarm water and counting, forward, from 1 to 25. There was no “negative verbal feedback” and no distracting video feed.

Before and after each test, researchers questioned the participant about his or her stress level. They also took saliva samples to measure levels of cortisol, the primary hormone associated with stress.

Among cannabis users, there was no difference in cortisol levels between those who completed the stressful scenario and those who completed the nonstressful scenario. Among nonusers, however, cortisol levels were significantly higher among those who got the ice-water-and-reprimands treatment.

And while cannabis users reported feeling more stressed after the less-pleasant of the two tests, they showed “a significantly smaller increase in subjective stress ratings” than nonusers, the researchers wrote.

The results surprised Cuttler, who had predicted that daily cannabis users, suddenly without their preferred coping tool, would experience unusually high stress levels during the experiment. But it ultimately confirmed the hypothesis of Ryan McLaughlin, one of the study’s authors and Cuttler’s husband.

“We kind of had a bet,” she said. “I had to admit that he was right, this time.”

The researchers stopped short of advocating cannabis use for its therapeutic effects.

“We’re not sure if it’s a good thing, a bad thing or potentially both,” Cuttler said.

Cannabis use might help protect against maladies associated with cortisol imbalances, including weight gain, hypertension and various psychological disorders, she said. But dampening stress responses in healthy individuals could have other negative effects.

“Cortisol helps to release energy stores and, more generally, just helps us to respond appropriately to threats in our environment,” Cuttler said.

In future experiments, she plans to examine long-term cannabis use in rats and home in on factors such as residual THC in users’ bloodstreams, she said.