Those who smoke marijuana often report that they do so in order to relax or relieve their stress. However, few studies have actually proven these effects in the past. Researchers at Chicago's University of Illinois and the University of Chicago have recently discovered that low levels of THC, the ingredient in marijuana that gets people "high," does indeed reduce stress. However, the dosage makes all the difference.
Those who used very low doses of marijuana reported a reduction in stress – for example, the jitters associated with public speaking. However, those who used slightly higher doses, enough to produce a minor "high," actually increased their levels of anxiety.
Because marijuana is a category 1 substance – and a highly regulated one at that – it is difficult for researchers to obtain the necessary permits in order to study the drug and its effects. This is why there is so little evidence to prove the stress-reducing capabilities of the drug, if any, because while it has been accepted as common knowledge that marijuana helps with stress, this is all essentially hearsay, as there are no reports to prove it.
Now, the fact that higher doses of THC have been proven to have the opposite effect and actually cause anxiety makes it even more important to understand dosages, especially in light of the increasingly legality – both medicinally and recreationally – of the drug.
Emma Childs is an associate professor of psychiatry at the UIC College of Medicine. She is also a co-author of this recently conducted study, in which she and her colleagues recruited 42 volunteers between the ages of 18 to 40 years old who had all used cannabis at one point in their lives, but who were not daily users of the drug. The participants were then divided up into three groups: low-dose, moderate-dose, and placebo.
The low-dose group received a capsule that contained 7.5 mg. of THC. The moderate group received 12.5 mg., and the placebo group, obviously, received a capsule that contained no THC whatsoever. The participants and the researchers were both left unaware as to who was in which group. The groups participated in two four-hour sessions, five days apart. During these sessions, they took their assigned pill, then relaxed for two hours to give the THC enough time to be absorbed into their bloodstreams.
During one session, the participants were instructed to spend 10 minutes preparing for a job interview. They then participated in a five-minute interview with the lab assistants, who did not offer the participants any feedback whatsoever in an effort to increase their stress levels. The participants were then asked to count backwards from a five-digit number by taking away 13 each time, for a total of five minutes. Child stated that this task is "very reliably stress-inducing."
During their second visit, participants took part in relaxing activities, like talking about their favorite movie, then playing solitaire. Those who received the lower dosages of THC reported feeling less stress than those who were given the placebo, and their stress levels dropped faster after the test. Those with the higher dosage, however, reported a more significantly negative mood before and during the tasks and were more likely to deem the tasks to be "challenging" and "threatening" before participating in them.