And those who already have drinking problems are less likely to recover if they smoke marijuana.
A study by researchers at Columbia University and the City University of New York suggest that adults who use marijuana are five times more likely to develop an alcohol use disorder (AUD) compared to adults who don’t smoke cannabis.
Conversely, marijuana users who already have a problem with alcohol abuse or dependence are more likely to see the problem persist, the researchers say. This finding aligns with another study that found that recovering alcoholics who smoked cigarettes were twice as likely to relapse — it’s best to stay away from smoking anything if you want to stay sober.
"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," Renee Goodwin, associate professor of Epidemiology at Columbia’s School of Public Health, said in a press statement. "Marijuana use also appears to increase the likelihood that an existing alcohol use disorder will continue over time."
The researchers looked at data from 27,461 adults who enrolled in the National Epidemiologic Survey on Alcohol and Related Conditions. All of these adults first used marijuana at a time when they had no history of alcohol use disorders.
The participants were then assessed at two different time points in the future, and adults who had used marijuana at the first assessment and then again over the following three years —
23 percent of the participants — were five times more likely to develop an alcohol use problem, compared to the adults who hadn’t used marijuana (5 percent).
Also, adults who had drinking problems but didn’t use cannabis were significantly more likely to be in recovery from their alcohol use disorders at the three-year follow-up, the researchers report.
"From a public health standpoint we recommend that further research be conducted to understand the pathways underlying these relationships as well as the degree to which various potentially vulnerable population subgroups -- youth, for example -- are at increased risk," noted Goodwin.
"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."
The study was supported by the National Institutes of Health and the National Institute on Drug Abuse, and the authors report no conflicts of interest.
While there’s a growing amount of evidence that advocates the benefits of smoking marijuana — it can help people overcome eating disorders and reduce the frequency of migraines, for example — but it’s important to also understand the risks that come with lighting up.