What happens to your body when you stop drinking alcohol?

Mocktails and so-called zero-proof beverages are growing commonplace on menus as more people opt to follow a "sober curious" or strictly teetotal lifestyle.

Many are familiar with the "Dry January" challenge to stop drinking alcohol for a whole month, but recently, the trend of saying goodbye to the dreaded hangover hasn't stopped with New Year's resolutions, especially amongst young people. Over the past two decades, the number of American undergraduate students who report abstinence from alcohol has risen by 8%, and in the U.K. in 2019, adults aged 16 to 24 were most likely to be teetotal, with 26% saying they never drink. 

People quit alcohol for many reasons: for some it's the calories, others, the risk of liver damage, increased blood pressure and potentially cancer. But what happens to the body when the average drinker calls it quits? 

Related: What does alcohol do to the body?

Given how many variables there are, it is hard to define an "average" drinker. The Centers for Disease Control and Prevention (CDC) describes "drinking in moderation" as having no more than one drink a day if you're a woman or two drinks a day if you're a man, on the days that you drink alcohol. Two-thirds of adult drinkers, however, say they exceed these levels at least once a month, a 2014 study found. 

The agency defines "binge drinking" as consuming at least four drinks in a 2 to 3 hour sitting, for women, and at least five drinks in the same time for men; "heavy drinking" is having at least eight or 15 drinks a week for women and men, respectively. A standard drink roughly translates to 12 ounces (0.35 liters) of beer at 5% alcohol by volume (ABV), or 5 ounces (0.14 L) of wine at 12% ABV. 

One way to represent the average drinker may be to focus on people who don't have a history of alcohol dependence. This is exactly what one study, published in the British Medical Journal, did in 2018.

Scientists recruited 94 volunteers who were on average 45 years old and asked them to stop drinking for a month. Before the challenge, participants were defined as "moderate to heavy drinkers" who drank around 258 grams of alcohol a week, roughly equivalent to about 18 standard drinks. No participants had a history of known liver disease or alcohol dependence. 

After a month, those who refrained from drinking experienced a range of positive health benefits not seen in a similar group of people who continued to drink. On average, the abstainers' blood pressure decreased by 6%, they lost around 3.3 pounds (1.5 kilograms) and their insulin resistance, which reflects a person's risk of developing diabetes, fell by 25%. 

"We didn't note this in the report but they also felt better, their concentration improved and they were able to sleep better," Dr. Kevin Moore, study author and professor of hepatology at University College London, told Live Science. The team saw these results after adjusting for changes in diet, exercise and smoking, so the changes could be linked to people's alcohol use. 

They also noticed that levels of proteins in the blood that promote cancer growth, namely epidermal growth factor (EGF) and vascular endothelial growth factor (VEGF) decreased by around 73% and 41%, respectively. Moore hypothesized that instead of causing cancer to develop in the first place, these findings may suggest that alcohol instead promotes cancer's growth once it gets a footing in the body. To confirm this speculation, however, the team would need to conduct a long-term study of moderate drinkers, the authors noted in their report. 

It is still unknown whether these positive effects of abstinence persist beyond a month, but Moore speculated it could be possible. "It's quite clear that alcohol has a physiological effect on the body, so I'd be surprised if all those effects just wore off," he said. 

So, does this mean people should stop drinking altogether?

"If you have cancer and you're worried about it growing then you should stop," he explained. This is common guidance given to cancer patients. For the wider population, he emphasized that when you stop drinking, you not only feel better but you also sleep better and your physical health improves. One downside of quitting for some though, he said, could be the social side of drinking and not wanting to feel left out. 

One important caveat is that Moore's study looked only at drinkers without a history of alcohol dependence. However, other research suggests that brain regions damaged by long-term alcohol abuse can start to repair themselves after people stop drinking.

In a 2023 study published in the journal Alcohol, scientists discovered that the outer layer of the brains of people with alcohol use disorder, which can thin as a result of alcohol abuse, regained its thickness after approximately seven months of abstaining from alcohol. Before abstaining, the study participants were drinking around 13 drinks a day over 12 months, Vice reported. 

The beneficial effects of abstaining cropped up even earlier, however. 

"Our team and other researchers have observed rapid recovery over two to four weeks of abstinence, for brain volume in multiple regions across the brain, in those with an alcohol use disorder," Timothy Durazzo, lead study author and professor of psychiatry and behavioral sciences at Stanford University, told Vice. 

Nevertheless, people who have AUD should take extra care before suddenly quitting or significantly decreasing their intake as they can experience symptoms of alcohol withdrawal. This is where the central nervous system becomes so reliant on the depressive effects of alcohol that, when a patient stops drinking, their brain stays in a "hyperactive" state. This can lead to symptoms including anxiety, insomnia and irritability, and in more serious cases, hallucinations, seizures and potentially death. 

"If an individual experiences shakiness and discomfort the morning after drinking, or drinks alcohol throughout the day, then going cold turkey could be dangerous," Katie Witkiewitz, a professor of psychology at The University of New Mexico, told Live Science in an email. 

In these cases, she said that talking with a healthcare provider about taking specific withdrawal medication could be helpful. Talk therapy, either as an individual or as part of a group, can also offer support through the process of quitting. 

This article is for informational purposes only and is not meant to offer medical advice.

Editor's note: This article was updated on Jan. 1, 2024 with information from a study published in 2023. The story was first published on Aug. 16, 2023.

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