A new study finds that Americans are drinking a lot more than they used to, and it could have major implications for health care costs in the future. The study, published in the journal JAMA Psychiatry, found that the number of adults who binge drink at least once a week could be as much as 30 million.

“This should be a big wake-up call,” said David Jernigan, director of the Center on Alcohol Marketing and Youth at the Johns Hopkins Bloomberg School of Public Health, according to an SFGate report. “Alcohol is our number one drug problem, and it’s not just a problem among kids.”

Women showed a bigger increase than men, and older Americans, minorities, and people with lower education and income showed an especially large jump.

“Alcohol use, high-risk drinking and alcohol use disorders increased in the U.S. population and across almost all sociodemographic groups, especially women, older adults, racial/ethnic minorities and individuals with lower educational levels and family income, according to a new study published by JAMA Psychiatry,” a statement from the journal reads. “Regular and detailed monitoring of trends in drinking and alcohol use disorders is important for the health of the nation. Monitoring alcohol consumption patterns and alcohol use disorders over time also is important for the planning and targeting of prevention and intervention programs.”