SANTA ROSA, CA - FEBRUARY 07:  A Russian River Brewing Company customer takes a sip of the newly released Pliny the Younger triple IPA beer on February 7, 2014 in Santa Rosa, California.  Hundreds of people lined up hours before the opening of Russian River Brewing Co. to taste the 10th annual release of the wildly popular Pliny the Younger triple IPA beer that will only be available on tap from February 7th through February 20th. Craft beer aficionados rank Pliny the Younger as one of the top beers in the world. The craft beer sector of the beverage industry has grown from being a niche market into a fast growing 12 billion dollar business, as global breweries continue to purchase smaller regional craft breweries such this week's purchase of New York's Blue Point Brewing by AB Inbev. (Photo by Justin Sullivan/Getty Images)
How alcohol affects your health
01:16 - Source: CNN
CNN  — 

Call them Generation Dry. More college-age Americans are choosing not to drink alcohol than they did nearly two decades ago, according to a new study.

Between 2002 and 2018, the number of adults age 18 to 22 in the United States who abstained from drinking alcohol increased from 20% to 28% for those in college. For those not in school, the percentage was 30%, up from 24% in 2002. Alcohol abuse among both groups decreased by roughly half.

“We’re encouraged by the significant decreases in alcohol use disorder – for both college and non-college students,” said Sean Esteban McCabe, director of the Center for the Study of Drugs, Alcohol, Smoking and Health at the University of Michigan School of Nursing and lead author of the study that published Monday in the journal JAMA Pediatrics.

While the study didn’t look at the reasons for the decrease, the authors suggested the changes could be down to the increases in the number of young adults who live with their parents as well as alcohol prevention and intervention efforts that have targeted college students.

It’s not just young Americans who are drinking less. Risky behavior such as binge drinking is much less prevalent in the United Kingdom than it used to be.

Researchers recently found that 29% of 16- to 24-year olds in the UK were non-drinkers in 2015 in the UK, up from 18% in 2005, while rates of binge drinking – defined as drinking twice the recommended daily limits – fell from 27% to 18%.

Misusing several substances

The most alarming trend the study identified was more young adults using or misusing several different substances, as opposed to just marijuana or alcohol.

“Points of concern that deserve more attention are the rise in co-use of alcohol and marijuana, as we know that polysubstance use can have more negative consequences and be more difficult to treat,” said Ty Schepis, a professor of psychology at Texas State University and a co-author of the study.

“For example, from 2015 to 2018, only 2.5% of young adults who abstained from both alcohol and marijuana reported misusing prescription drugs, while 25.1% of co-users misused prescription drugs,” Schepis said.

“That is a tenfold difference with potentially dangerous consequences.”

The study found that marijuana use increased from 27% to 31% among college students from 2002 to 2018 and 26% to 30% among those not in college – but the researchers didn’t find an increase in problematic marijuana use.

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The study said US policymakers must “find ways to address the changing landscape of substance use behaviors by providing support to the increasing number of young adults who are abstinent, while also creating interventions to address the increases in marijuana use and co-use of alcohol and marijuana.”

The study examined data collected each year as part of National Survey on Drug Use and Health. The sample included 182,722 adults ages 18 to 22 years.

Although drinking by people under the age of 21 is illegal in the US, people ages 12 to 20 years drink 11% of all alcohol consumed in the United States, according to the CDC.