does cannabis lead to hard drugs

Does cannabis lead to hard drugs?

Cannabis use does not lead to experimentation with harder drugs,
Researchers say.
Researchers said it does not act as a "gateway" drug, and that measures to curb cannabis use does not have a knock-on effect on the use of harder drugs.
Instead, they say teenagers begin using cannabis, or marijuana, simply because it is the most available drug.
They said they were not advocating decriminalizing cannabis.
But they did question whether efforts to control drug use should be so focused on cannabis.
The research comes as the UK government prepares to announce a package of new measures to tackle drug misuse, which will focus on harder drugs such as cocaine and heroin.
Personality
In the US study, researchers from the independent Rand Drug Policy Research Center in Santa Monica, California, looked at data from the National Household Survey on Drug Abuse between 1982 and 1994.
They concluded that teenagers who took hard drugs did so whether they had first tried cannabis or not.
Researchers said the likelihood of cocaine or heroin users having previously used cannabis was high, not because of the gateway effect, but because of their personalities.
People who are predisposed to use drugs and have the opportunity to use drugs are more likely than others to use both marijuana and harder drugs.
Marijuana typically comes first because it is more available.
The findings would impact on drug policies, because they suggested reducing or eliminating the availability of cannabis would be "unlikely to make a dent" in the hard drug problem.
Unfortunately many of the studies have been quite small. They have not used large sample sizes, so the evidence is not strong.
The UK government downgraded cannabis to a class c drug in 2004. Then stronger negative evidence emerged. It found that cannabis use could trigger mental health problems in people who are vulnerable to such problems. In 2009 the decision to downgrade was reversed and cannabis is now a class b drug again.