For some teenagers, heavy drinking begins well before they accept their high school diploma, according to a new University of Michigan study.

The average time of escalation from first drink to high-intensity drinking (eight or more drinks in a row for women; 10 or more drinks in a row for men) occurs within two years of first trying alcohol. And teens who initiated high-intensity drinking at younger ages or who had a faster escalation to high-intensity drinking were at greater risk.

The findings, published in JAMA Pediatrics, also indicate that having a family history of alcohol problems and not attending a four-year college by age 20 were associated with starting high-intensity drinking earlier.

U-M researchers followed a national sample of adolescents from the Monitoring the Future study who, as 12th grade students in 2018, reported alcohol use in the past 30 days. This group of 451 participants was surveyed again in 2020 at age 20 as part of the Young Adult Daily Life Study.

The analysis focused on the grade level of initiating any alcohol use, first binge drinking (4+ drinks for women and 5+ drinks for men) and first high-intensity drinking. Respondents disclosed current consumption rates and high-intensity drinking frequency, as well as personal background information including sex, race/ethnicity, family history of alcohol problems and college status.

Attention to heavy alcohol consumption often tends to focus on drinking in college, where parties, tailgates and other events foster this behavior. But the fact that there is heavy drinking in high school suggests that “waiting until college for intervention may be too late for some people because these patterns have already started for many of them,” said Megan Patrick, the study’s lead author and a research professor at the Institute for Social Research.

“Additionally, young adults who do not attend college are often overlooked but are also in need of intervention resources,” she said. “I think it’s important to be aware of when teens start drinking, and whether and how quickly they escalate to heavier drinking so we can appropriately target prevention and intervention efforts.”

The study was funded by the National Institute on Alcohol Abuse and Alcoholism and the National Institute on Drug Abuse. The study’s authors included Rebecca Evans-Polce, Brooke Arterberry and Yvonne Terry-McElrath.