Just one of many studies.
“The study found that those who used pot daily were three times more likely to have a psychotic episode compared with someone who never used the drug.
Those who started using cannabis at 15 or younger had a slightly more elevated risk than those who started using in later years.
Use of high-potency weed almost doubled the odds of having psychosis compared with someone who had never smoked weed, explains Di Forti.”
Let’s look at studies on those who were habitual drinkers starting at 15.
This is not about 15 year olds. But, for adults.
A
Several years ago, Canada was treating patients with medical marijuana. The complaint was always the same: “This stuff is too weak”.
From your link:
‘the study doesn’t prove causality, cautions Dr. Diana Martinez, a psychiatrist and addiction researcher at Columbia University. “You can’t say that cannabis causes psychosis,” she says. “It’s simply not supported by the data,” she says.
‘Lisdahl agrees. In order to show causality, one would have to follow people over time — before they started using weed to years later when they have their psychotic episodes, she says. “You need twins in the studies, you need genetic information,” among all other kinds of data, she says.’