Young adults aren't drinking as much as they used to. In fact, more than a quarter don't drink alcohol at all, recent surveys show.
It's good news for health. But there is also a downside in the data: While alcohol use is falling among 18-to-22-year-olds, marijuana use is inching upward. The number of young adults using both alcohol and marijuana is also rising, heightening concerns about a future surge in substance abuse problems, new research shows.
The bad news is that the number of college-age young adults saying they used marijuana at least once in the previous year has increased, from 33% to 37%.
The vast majority who said they used marijuana also used alcohol. We found that the increase in young adults using both was a result of young adults who used alcohol taking up marijuana, too.
This increase in using both alcohol and marijuana is an important warning sign, because young adults in that group also had much higher rates of other illicit drug use, like cocaine, and prescription drug misuse, involving medications like opioids or benzodiazepines.
That may signal that a greater number will need substance use treatment in the coming years.
One theory for the shifting trends in alcohol and marijuana use is that adolescent substance use is now starting at later ages.
The data support this: The numbers of adolescents starting alcohol use has declined somewhat, while more college-age adults are first-time alcohol and marijuana users. Why that shift is occurring is less clear, but one theory is that adolescents have been engaging in more virtual contact than face-to-face contact in recent years and they rarely use substances when they're alone.
Changing regulations likely also play a role. Marijuana is now legal for medical or recreational use in an increasing number of states.
Attitudes toward alcohol and marijuana have also changed over the years, particularly for marijuana.
The Monitoring the Future study, which has tracked substance use in adolescents and young adults since 1975, indicates both a sharp decline in disapproval of marijuana among middle and high school students and a decline in how harmful they perceive marijuana to be. In fact, more young people in that age group now see more harm from regular alcohol use than disapprove of marijuana.