Pubdate: Wed, 29 Aug 2012 Source: Manchester Evening News (UK) Copyright: 2012 Manchester Evening News Contact: http://www.manchesteronline.co.uk Details: http://www.mapinc.org/media/1313 Author: Alice McKeegan EX-ADDICT BACKS NEW RESEARCH SHOWING CANNABIS DOES AFFECT IQ A woman who started smoking cannabis at the age of 15 has warned of the dangers of the drug after new research showed it can lower the IQ of young teenagers and may cause permanent mental impairment. Zoe Houston, 38, smoked up to 25 joints a day after getting hooked just months after leaving school. Her addiction became so bad that she dropped out of college because she couldn't concentrate on her studies - and needed to earn cash to feed her habit. Zoe smoked the drug for 21 years - going from job to job and 'drifting' in life - until she decided to seek help. She enrolled on a treatment programme with Stockport-based Acorn Treatment and finally got clean. Now Zoe helps out at Acorn's treatment centres across the region and supports people going through similar problems. She has backed a major study by British and American researchers showing that the most persistent users suffer an average eight-point decline in IQ between adolescence and adulthood. Scientists believe smoking cannabis from around puberty may disrupt developing and vulnerable brain circuits. Users experienced significantly more attention and memory problems than non-users, the study revealed. This was the case even after taking account of different educational backgrounds and use of alcohol and other drugs. Zoe, from Lancashire, said: "I started on cannabis at 15 and by 16 I was smoking from morning to night. A group of my friends also used it and I guess we thought it was cool at the time. "There's a misconception that it's only a herb and it's not dangerous but that's simply not the case. I had 20-odd jobs by the age of 30 and couldn't settle in anything. "My memory was horrendous and I really struggled so I definitely agree with the study's findings. My advice to other people is not to use cannabis at all - it's not worth it." Zoe sought help two years ago and has been clean ever since. It took her two months to stop completely - and she believes it was the best thing she could have done. The international research team, led by US psychologist Dr Madeline Meier, from Duke University in Durham, Carolina, wrote in the journal Proceedings of the National Academy of Sciences: "Persistent cannabis use was associated with neuropsychological decline broadly across domains of functioning even after controlling for years of education. "Impairment was concentrated among adolescent-onset cannabis users, with more persistent use associated with greater decline. Further, cessation of cannabis use did not fully restore neuropsychological functioning among adolescent-onset cannabis users." The researchers analysed data on 1,037 individuals enrolled into the Dunedin Study, a large lifestyle and health investigation based in New Zealand. For help on drug issues, contact Acorn on 0161 484 0000. - --- MAP posted-by: Jay Bergstrom