Lighting up a joint now could make you more likely to crack a bottle later—and have issues putting it down, or so suggests a pair of new studies. In the first, published in Drug and Alcohol Dependence, researchers say they've found that marijuana users seem to have an "increased vulnerability" to developing an alcohol use disorder (defined as alcohol abuse or dependence) as compared to their pot-free counterparts. They used data on 27,461 adults who took part in the National Epidemiologic Survey on Alcohol and Related Conditions and reported having no AUD in 2001 and 2002 (aka, "Wave 1"). Fast-forward three years to "Wave 2," and those who reported marijuana use originally were 5.4 times more likely to have an AUD, per the study.
The second study, published in JAMA Psychiatry, made use of NESARC data as well, but a slightly broader slice: 34,653 adults. Its findings were broader as well: Those who used pot in Wave 1 were roughly six times more likely to have any kind of substance use disorder three years later; when it specifically came to an AUD, this study found they were 2.7 times more likely to have developed one (the reason for the discrepancy is unclear). Those researchers also looked at other drug use disorders and nicotine dependence; the likelihood was higher for pot smokers in both cases. But a psychology professor and legalization advocate tells HealthDay he's skeptical. As far as the pot-to-other-drugs "gateway" theory goes, "I am unable to see this association after 40 years of clinical experience." (Another study finds that teens who smoke pot don't get dumber as a result.)