Not enough data?

Cully Stimson reports:

A definitive study published this week by the Journal of Addiction by Professor Wayne Hall of Kings College London, shows that marijuana is highly addictive, causes mental health problems and is a gateway drug to other illegal dangerous drugs.

Hall’s research, conducted over the past 20 years, confirms what other studies have shown: that regular adolescent marijuana users have lower educational attainment than non-using peers, that they are more likely to use other illegal drugs, that adolescent use produces intellectual impairment, doubles the risk of being diagnosed with schizophrenia and that, not surprisingly, increases the risk of heart attacks in middle-aged adults.

Read more here.