About 10 percent of people who drank excessively also met the clinical definition for alcohol dependence. The vast majority of excessive drinking is binge drinking, a pattern of behavior where men consume roughly five or more drinks and women consume four or more within a short period of time.
But the big takeaway here isn't that people who drink too much don't need to worry about their habits, said study author Bob Brewer, who heads the CDC's Alcohol Program in the National Center for Chronic Disease Prevention and Health Promotion. Rather, the study shows that combating excessive drinking as a public health problem needs to go beyond focusing only on alcoholism, a chronic medical condition.
"Knowing that nine out of 10 people who drink too much are not alcohol dependent in no way diminishes the impact of alcohol dependence as a problem. It just says the problem we're dealing with is bigger than that," Brewer said. "We need to look at this problem with a wider-angle lens and consider not just treatment for those who need it."
Alcohol dependence here is a "medical problem" and "based on the consequences and the science and symptoms of someone's drinking behavior," Brewer said. People with alcohol dependence report symptoms such as withdrawal, unsuccessful attempts to cut down or stop drinking and continuing despite problems arising from drinking. While about one in three adults drinks excessively, only one in 30 (or 3.5 percent) meets the clinical definition for alcohol dependence.
The study also found that excessive and binge drinking, as well as alcoholism, was most common among 18- to 24 year-old men, with binge drinking most prevalent among people coming from households with an annual income of $75,000 or more. But alcoholism was most common among people who had family incomes of less than $25,000 and people who reported binge drinking 10 or more times in the past 30 days.
The data comes from three years of the National Survey on Drug Use and Health, in which 138,100 people from around the country answered questions about their drinking habits. That means all of the information was self-reported, and that kind of data is usually considered under-reported, the study authors noted.
Brewer said there are certain strategies that help reduce excessive drinking, such as increasing the price of alcohol and considering the geographic concentration of liquor licenses. The study "really gives us some further insight about what we need to be doing about dealing with this critical public health problem," he said.