WATCH: Controversial Study Says Teen Pot Use Could Be Fatal

A Swedish study of 45,000 Swedish men from 1970 to 2011 discovered that heavily smoking Marijuana can shorten life spans. The study found a correlations between heavy pot use and cancer, lung, and heart disease when the subjects smoked in their teenage years.

The above video report provides more details. Also, here is an article that digs into the study and its findings.