Smoking cannabis is unlikely to increase your risk of killing yourself. Researchers from Cardiff University looked at data on more than 50,000 Swedish military recruits. Sweden has conscription and the study covered 50,087 men and women who were conscripted between 1969 and 1970 when they were aged between 18 and 20. Over the next 30 years 600 of the sample killed themselves. Those who admitted to smoking cannabis when they were conscripted were 62% more likely to kill themselves during the follow-up period. However, once other factors such as childhood behaviour problems, psychological adjustment, mental-health problems, drinking, smoking and parental drug use were taken into account the link between cannabis use and suicide disappeared.
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