The Telegraph has posted an article on a report made by the U.S.A. that says the strength of Marijuana is at its highest in 30 years.

"This report makes it more important than ever that we get past outdated, anachronistic views of marijuana," said John Walters, director of the White House Office of National Drug Control Policy.

The US Government believes the increase in potency is down to sophisticated growing techniques used by drug traffickers.

He said baby boomer parents might have misguided notions that the drug contains the weaker potency levels of the 1970s but said it can cause psychological, cognitive and respiratory problems, and lead users to "harder" drugs such as cocaine and heroin.

I've been reading FUD like this for years, yes, it's a lot more potent due to indoor growing and advanced techniques developed over the years, but there's no research that says higher potency causes psychological, cognitive and respiratory problems.