Marijuana users more likely to be paranoid – study /Stuff New Zealand, 2 Mar 2005

http://www.stuff.co.nz/stuff/0,2106,3203576a11,00.html
"Heavy marijuana use will make people paranoid, a Christchurch study shows. Researchers at Otago University's School of Medicine in Christchurch have found that daily marijuana users are about 1.5 times more likely than non-users to have psychotic symptoms such as thinking other people are aware of their private thoughts or feeling that something is terribly wrong with their bodies. "