A new study has revealed heavy marijuana use during teenage years can lead to early death.
Analyzing more than 45, 000 men, scientists followed a group who underwent military training in Sweden between 1969 and 1970.
They were tracked on the National Cause of Death Register until 2011, by which time around 4,000 of the men in the group had died.
Published in the American Journal of Psychiatry, the research found that men who used marijuana heavily in their late teens were 40 per cent more likely to die by the age of 60.
Heavy use was defined as teens who used marijuana more than 50 times.
The study also discovered that the risk of death from an accident or suicide was directly proportionate to the amount of marijuana used by the men as teens.
According to addiction expert Scott Krakower, cannabis users in general have poorer health.
Speaking to CBS News, Krakower said: "'Marijuana users generally may have poorer diets and they might be tobacco smokers. There's an increased linkage between weed and tobacco."
Member of the American Psychiatric Association's Council on Addiction Psychiatry, Dr Kevin Hill, told CBS: "One of the key messages from a study like this comes down to two words: dose matters."
Heavy use at a young age is linked to cognitive issues and poor psychological health, said Hill.
He referenced a 2012 study which revealed early, regular marijuana use, as described in this new study, led to an "eight-point decline in IQ over time" and a higher chance of developing a psychotic disorder.
International research has also found a direct correlation between high cannabis use and lower paid employment and relationship difficulties.
A study published in the journal Clinical Psychological Science found regular cannabis users experienced downward social mobility, more financial trouble and antisocial behaviours at work as well as control abuse and intimate partner violence within relationships.