A study has found cannabis smokers are five times more likely to become alcoholics (Picture:Bruce Bennett/Getty Images)

If you smoke cannabis you are five times more likely to become an alcoholic.

That is the verdict of new research carried out by two American universities which also suggests drinkers who smoke will see the problem persist.

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The study used data from more than 27,000 adults who had enrolled in a survey on alcohol and related conditions.

It looked at those who had first smoked weed at a time when they had no history of alcoholism.


Researchers discovered that adults who used cannabis over three years were five times more likely to develop an alcohol problem compared with those who didn’t.

The study looked at 27,000 American adults (Picture: Miguel Schincariol/AFP/Getty Images)

Also, problem drinkers who didn’t smoke cannabis were more likely to be in recovery three years later.



Renee Goodwin, an associate professor at the Mailman School of Public Health, led the study.

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She told EurekAlert: ‘Our results suggest that cannabis use appears to be associated with an increased vulnerability to developing an alcohol use disorder, even among those without any history of this.

‘Marijuana use also appears to increase the likelihood that an existing alcohol use disorder will continue over time.’

She called for more research to be carried out to see, for example, if the youth were affected in the same way as adults.

‘If future research confirms these findings, investigating whether preventing or delaying first use of marijuana might reduce the risk of developing alcohol use disorders among some segments of the population may be worthwhile,’ she added.

The study was carried out by researchers at Columbia University’s Mailman School of Public Health and the City University of New York.

It used data from the National Epidemiologic Survey on Alcohol and Related Conditions.

It is possible to view the full research online in the journal Drug and Alcohol Dependence.