Heavy teen marijuana use may cut life short by 60

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.