Teenage cannabis use reduces IQ permanently

Study finds marijuana is 'safe' for over-18s but 'risky' for younger users

LAST UPDATED AT 11:02 ON Tue 28 Aug 2012

THE LATEST results from a major scientific study ongoing since 1972 show that smoking cannabis as a teenager can permanently lower your IQ. But the international team of scientists also found that smoking the drug was 'safe' for over-18s.

Prof Terrie Moffitt, of the international group of scientists who conducted the study, said they had ruled out other factors such as alcohol use, dropping out of school or use of other drugs and were sure the IQ loss was related to cannabis alone.

She told the BBC the effects included loss of concentration, speed of mental reactions and problems with memory. They appeared to remain in place even if the subjects stopped smoking the plant's leaves or resin for a year.

But the effects were only found to be irreversible in those who had started smoking the drug as teenagers: Moffitt said those who had started later in life suffered the same problems but recovered if they stopped using the drug.

She speculated that the problem might be because the young people's brains were still growing. The study was started when its 1,000 test subjects, from Dunedin in New Zealand, were just children and had not started using cannabis.

It continued through their teenage years and up until they reached the age of 38. Individuals who started using cannabis as adolescents and continued smoking it for years suffered an average decline of eight IQ points.

Moffitt, of King's College, London, said: "This work took an amazing scientific effort. We followed almost 1,000 participants, we tested their mental abilities as kids before they ever tried cannabis, and we tested them again 25 years later after some participants became chronic users.

"Participants were frank about their substance abuse habits because they trust our confidentiality guarantee, and 96 per cent of the original participants stuck with the study from 1972 to today.

"It is such a special study that I'm fairly confident that cannabis is safe for over-18 brains, but risky for under-18 brains." · 

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I think this study is actually no use whatsoever. As we all know 'teens' develop at different rates and that includes the growth of their brains. Even if this study had any merit to it at all, you cannot put an age definition line across the whole range and say it does or doesn't effect them.

Yep, sounds like a desperate attempt to salvage 40 years of research. One thousand test subjects? Out of this 96 percent who stuck with the program, how many actually became chronic users? Surely if it was a significant number they would have presented the figures. An 8 point IQ drop (gasp) evidenced by the IQ tests of a handful of stoners proves naught.

This study is intended solely to prop up the dying regime of cannabis prohibition.

Around the world, governments are neglecting their responsibility towards young people by their refusal to regulate cannabis in a proper manner.
Teenagers are currently able to easily buy cannabis from street dealers who do not ask for ID, only money. This situation of governments continuing to allow easy access of all drugs to street dealers is totally unacceptable. If governments would regulate the sale and use of cannabis, then our young people would be protected from moral-free drug dealers.
Take the USA, where alcohol sales are prohibited to under 21's. Many American teenagers are into sport. They know that they cannot legally access alcohol and so they turn their attention towards sporting activities - proof that a licensing system of the drug alcohol most definitely works.
If people over the age of 18 were legally able to purchase cannabis, and if the government developed a regulated structure for its consumption - along the lines of cannabis cafés in Holland - then the link between cannabis and hard drugs would be permanently broken. The image of the young, lonely, methadone addict would then be a thing of the past.
It's way past time to end this diabolical state of affairs concerning our teenage youth - it's time for the world's governments to regulate the cannabis market for adults over the age of 18.

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