Cannabis doubles the risk of paranoia, suggests study
- Published
Cannabis can make us paranoid meaning we don't trust those around us
Smoking cannabis can double the risk of developing the disorder, an expert on paranoia has told Newsbeat.
Professor Daniel Freeman is a clinical psychologist at Oxford University and says teenagers are most vulnerable.
The results of his study, the largest ever looking at the effects of cannabis, suggests it can cause paranoia.
The active ingredient of Cannabis is THC and Prof Freeman says it "raises levels of suspiciousness".
It can also lead users to ''misread situations''.
His study focussed on people who had taken the drug at least once before.
Prof Freeman says that paranoia is our most common fear, with over half the population having "slight paranoid thoughts".
Many studies have been done on the general psychotic effects of THC but this was the largest dedicated solely to paranoia.
It focussed on what Prof Freeman calls "every day suspiciousness", where we have to judge what people are thinking and who we should trust.
More than 100 cannabis users took the drug and were placed in simulated social situations before being questioned on how they felt.
The results show THC can make noises appear louder and lights more bright. Thoughts might echo in users heads and it can even distort their perception of time.
While Prof Freeman accepts some people enjoy these effects, he warns that young people are more likely to have a negative reaction.
"THC makes the world feel different and that can be confusing," he said. "It can make people worry and that has an impact on their self-esteem.
"All these issues stem from the paranoia making us feel negative about ourselves. We start to worry and worry leads us to the worst conclusions."
He suggests that teenage years are the "real window of vulnerability" and young users "severely raise their risk" of developing a disorder.
"Most people will be fine", he told Newsbeat.
But with nearly 14% of 16 to 24-year-olds using the drug each year he says that's lots of people putting themselves at risk.
When using the drug, he recommends asking friends how they feel, but knows this is unlikely given the sense of mistrust THC generates.
He says the best way to clear your head of paranoid thoughts is to stop smoking cannabis.
"The increased paranoia only happens when there's THC in your bloodstream," he said.
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