We found that THC at low doses reduced stress, while higher doses had the opposite effect,” Emma Childs, an associate professor of psychiatry at the University of Illinois at Chicago and an author of the study.
People on the low dose reported being more relaxed than those on the placebo, and their stress levels dissipated more quickly after the tasks. But people on the high doses paused more in the job interview and reported the tasks to be stressful, challenging, and threatening.
The Cannabist has calculated the amount of THC people get from an average joint. According to a study cited in their analysis, an average joint weighs about .32 grams. They say that smoking half of that would give users 9 to 11 mg of THC, assuming that about the same amount of THC would just burn off. That’s right in between the “low” and “high” doses used in the study.
The Cannabist’s formula multiples the weight of the joint by the THC potency of marijuana to tell you how much THC you’d ingest. So in a .32 g joint with a 13% potency, you’ve got about 42 mg of THC. The low 7.5 mg dose from the study would therefore be 18% of that joint, and the high 12.5 mg dose would be about 30% of it. (It’s worth noting, however, that exact calculations are hard since some will always burn off. Plus, some joints are a lot bigger, with another commonly cited average being about .75 grams.)