What Happens When You Quit Casual Drinking? Scientists Reveal the Effects

"For many populations, there is not a safe level of drinking."

Over thousands of years, drinking alcohol has become embedded in human culture. But an increasing amount of evidence shows that even a casual relationship with alcohol can come at a cost. While scientists aren’t lobbying to enforce sobriety, there now appears to be a shift in their thinking: The body can be changed by booze, even without the extremes of alcoholism.

The effects of moderate drinking — and quitting — were evaluated in a study published Monday in the Canadian Medical Association Journal. In it, scientists observed how changing drinking habits shifted the mental and physical well-being of 10,385 Chinese people, comparing those results to data from a representative survey of 31,079 Americans.

Over the four-year study period, lifetime alcohol abstainers reported the highest level of mental well-being. But the people who drank and then quit — females in particular — approached the same level of mental well-being as lifetime abstainers within four years of going sober in both the Chinese and American populations.

The study suggests that even if you’re just a casual drinker to begin with, going sober can have profound benefits.

How Quitting Alcohol Affects Mental Health

In the study, both Chinese and American participants answered previously established questionnaires on physical and mental well-being twice over a four-year period. These people included lifetime abstainers, persistent moderate drinkers, and those who drank when they were first surveyed and had quit by the second survey. Throughout, moderate drinking was defined as 14 drinks or less per week for men and seven drinks or less per week for women.

On average, the mental well-being of the women who quit drinking approached the level of lifetime abstainers within the four-year period. There was, however, very little change in the mental well-being of the men who quit. These results were persistent even after the scientists adjusted for sociodemographic characteristics, body mass index, and smoking status.

Alcohol, whiskey
In the United States, low-risk drinking is defined for women as no more than three drinks a day and no more than seven drinks a week.

Study co-author Herbert Pang, Ph.D., an assistant professor at the University of Hong Kong, explains to Inverse that by validating the findings across both Chinese and American populations, the team showed that their observations were indeed the result of people’s drinking habits and not cultural factors. Since alcohol consumption isn’t as common in China as it is in the United States, any patterns that emerged from the data would demonstrate the effects of drinking, not of local social norms.

Understanding Male and Female Differences

It’s not clear why quitting led only women to experience a favorable change in mental well-being. “It is possible that alcohol cessation may reduce stressful life events, such as conflict within a family, difficulties in employment, and legal troubles, resulting in improved mental well-being,” Pang says.

“Further studies are needed to establish clearly the impact of alcohol use on mental and physical well-being before alcohol is recommended as part of a healthy diet.” 

Co-author Mary Schooling, Ph.D., a professor at the CUNY Graduate School of Public Health & Health Policy, who advised on the study, says any explanations for the sex difference the team observed remain speculative.

“It could be that men and women react differently to giving up alcohol, because of physiological differences,” Schooling tells Inverse. “Alternatively, alcohol use is a complex activity that may represent more than intake of alcohol. For example, it could be an indicator of active social life in men, but of a guilty pleasure in women.”

“As such, giving up alcohol would also represent different things in men and women, and hence have different associations with well-being.”

drinks, beer
"Safe" drinking limits vary across countries.

In part, the incomplete understanding of these effects is due to the fact that light drinking has been studied a lot less than heavy drinking. Heavy drinking is well known to be harmful; lighter drinking less so.

Is Light Drinking Healthy for You?

Even as some evidence shows that light to moderate drinking is good for you, it pales in comparison to the findings showing that it is not.

In August 2018, for instance, scientists reported in The Lancet that, despite research suggesting low levels of alcohol consumption can have protective effects on ischemic heart disease and diabetes, the “safest level of drinking is none.” The authors determined that any amount of alcohol use is linked to worsening health conditions, although the risk is also contingent on how much a person drinks.

“Each individual can decide what they think that acceptable risk is, but there’s no free lunch, or free drink, so to speak,” lead author and University of Washington Institute for Health Metrics and Evaluation Senior Researcher Max Griswold, Ph.D., told Inverse at the time. He emphasized that the goal of the research wasn’t to scare people into abstaining but to help them understand that drinking is a risk at any level.

Kimberly Nixon, Ph.D., an associate professor at the University of Texas at Austin’s Waggoner Center for Alcohol and Addiction Research, tells Inverse that “for many populations, there is not a safe level of drinking.” She points out that the National Institute on Alcohol Abuse and Alcoholism states that one drink a day for women and two drinks a day for men is considered low risk. That risk rises dramatically above four drinks a day for women and five drinks a day for men.

What Is a Safe Amount to Drink?

One barrier to understanding the risks of drinking is that safety limits vary widely across countries. The US, Canada, and Sweden share similar limits, while the limits for low risk are almost 50 percent higher in Italy, Portugal, and Spain. In the United Kingdom, the upper safe limit of drinking is six pints of beer or seven glasses of wine per week — a much lower threshold than those other countries. That low threshold is supported by research showing that having 10 or more drinks per week is linked with one to two years shorter life expectancy.

Another major issue is that it’s common for people who think they are drinking moderately to actually be binging — and when it comes to binging, the evidence of its damage is clear.

WATCH: A Hungover Neuroscientist Explains What Happens to Your Brain When You are Hungover

More research on the risks of casual drinking is needed, but fortunately, there are signs that we can recover from some of the damage alcohol causes. For example, though alcoholism leads to changes in brain tissue volume, the brain can experience rapid recovery within 14 days of abstinence.