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Cannabis doubles the risk of psychosis
By Evening Standard Last updated at 00:00am on 01.03.05Smoking cannabis almost doubles the risk of psychotic mental illness such as schizophrenia, new research revealed today.
Based on data gathered over 25 years, researchers in New Zealand suggested that effects on the brain caused by cannabis probably explained higher rates of psychosis. It was not likely to be due to people with mental illness having a greater wish to smoke.
They analysed information obtained on 1,055 people born in 1977 who took part in a public health study which followed their fortunes over 25 years.
At the ages of 18, 21 and 25, participants were questioned about cannabis use. They were also assessed on aspects of their mental health. The team, from the University of Otago, concluded that cannabis was related to increased rates of psychosis.
