Swedish researchers analyzed the records of more than 45,000 men beginning in 1969 and 1970. The scientists from the Karolinska Institute in Stockholm reported that 4,000 died during the 42-year follow-up period, and men who'd used marijuana heavily at ages 18 and 19 were 40 percent more likely to die by age 60 compared to guys who hadn't used the drug.
Links
[1] http://www.cbsnews.com/news/heavy-teen-marijuana-use-may-cut-life-short-by-60/
[2] http://rethinkpot.org/tags/teens
[3] http://rethinkpot.org/tags/usage
[4] http://rethinkpot.org/tags/death