Psychosis risk doubles for pot smokers, says study: What you smoking?

(CBS) Don't tell Snoop Dogg, but a new study adds to mounting evidence that there is a link between smoking pot and psychosis, especially for young people.

According to a 10-year European study of adolescents and young adults, smoking pot doubled the risk of later having psychotic symptoms. Dutch researchers working in Germany did their best to weed out those who had psychotic symptoms before the study in an effort to remove kids who might be self-medicating with marijuana, said Reuters.

The findings echo previous research, including a 2010 Australian study which also found a doubled risk of psychotic symptoms for young people smoking six years or more.

Each year, more than 2 million Americans 12 or older smoke marijuana for the first time, according to the National Survey on Drug Use and Health.

Still, some outside researchers are cautious to draw a direct link between smoking weed and mental problems.

"It's important to remember that psychosis is a very complex bio-psycho-social phenomenon," Peter Kinderman, clinical psychology professor from the University of Liverpool, told Reuters. "But this important paper certainly reminds us that there's a strong link to the use of cannabis."

The findings led by Jim van Os from Maastricht University were published in the British Medical Journal.