5 Things Drinking Too Much Alcohol May Be Doing to Your Body

When you wake up with a hangover, it’s a no-brainer that last night’s drinks didn’t do you much good. But, despite what you hear about the health benefits of an occasional glass of wine, overdoing it on alcohol can have a much bigger impact on your body than just one day of misery.

“People tend to forget that alcohol is a depressant,” says Hilary Sheinbaum, author of The Dry Challenge: How to Lose the Booze for Dry January, Sober October, and Any Other Alcohol-Free Month. She has given up drinking alcohol at least one month out of the year since 2017 and has noticed a variety of positive effects while doing so, from improved digestion to better sleep.

“After the first 10 days without alcohol, I recognized that my mood was more elevated,” she recalls. “I went from five hours of sleep a night to seven or eight, and I was more energized and excited to get up in the morning. Even my skin changed.”

The evidence is more than anecdotal. A few years ago, the cumulative effects of heavy drinking were revealed in a large-scale study of almost 600,000 drinkers in 19 countries. Researchers found that people who downed approximately 14 to 25 drinks per week had an average life span up to two years shorter than people who drank a maximum of around seven alcoholic drinks per week. The findings, which were published in the journal The Lancet, also revealed that as weekly alcohol consumption increased, so did the risk of stroke, heart failure, and death from hypertension or aortic aneurysm.

How Much Alcohol Is Too Much?

The Centers for Disease Control and Prevention (CDC) defines heavy alcohol consumption as eight or more drinks per week for women and 15 or more for men. For drinkers, the CDC recommends limiting to moderate alcohol consumption, which is defined as up to two drinks per day for men and up to one drink per day for women, on days when alcohol is consumed.

“I think that, often, people don’t realize how much alcohol they consume on a monthly basis,” says Sheinbaum. “When considering that someone might have a few drinks on weekends, a glass of wine with dinner, or a beer (or two or three) watching sports, it can add up.”

Also, if you only drink once or twice a month, it’s easy to think you’re not overdoing it. But, when it comes to excessive alcohol use, CDC data indicates that the main problem for most people is drinking excessively on a single occasion, known as binge drinking. That means four or more drinks for women, and five or more for men, over two to three hours. According to the CDC, one in six U.S. adults engages in this behavior, and while the majority do not have alcohol use disorder, it’s definitely not healthy.

“Having one drink every day of the week is not the same as having seven drinks on a Saturday,” says Kathy Jung, PhD, director of the National Institute on Alcohol Abuse and Alcoholism Division of Metabolism and Health Effects. “Binge drinking is never safe.”

It’s important to know exactly how much alcohol you are drinking. The CDC defines a drink as 5 oz of wine, 12 ounces (oz) of any beer with 5 percent or less alcohol by volume — an amount exceeded by many craft brews — or 1.5 oz of distilled spirits, such as vodka or rum. These serving sizes are often inflated by overpouring, so you may be drinking more than you realize.

What Other Effects Can Alcohol Have on Your Body?

In addition to taking years off your life, excess drinking can have other significant effects on your body and mind. Here are five that research has unearthed:

1. Alcohol Can Change Your DNA — and Make You Crave More Alcohol

Yes, you read that right. Both binge drinking and heavy drinking can actually change your genetic makeup and leave you wanting more alcohol, more often, according to research.

When researchers compared groups of binge drinkers and heavy drinkers with moderate drinkers (one drink per day for women and up to two for men), they found that an alcohol-induced gene modification process called methylation changed two genes in the binge drinkers and heavy drinkers. One of those genes, known as PER2, affects the body’s biological clock, and the other, POMC, regulates the stress response system. The result of these changes is an increased desire for alcohol. This finding provides evidence that excessive drinking can actually alter your genes and that these specific changes in gene function are associated with an increase in the desire to drink alcohol. That may help explain why alcohol use disorder is so powerful and affects so many.

2. Alcohol Increases the Risk of Certain Cancers

The National Cancer Institute (NCI) cites several studies, including one meta-analysis that showed alcohol increases the risk of certain cancers, including those that affect the mouth, throat, liver, and breasts. Another study, published in September 2021 in the journal Nutrients, also noted that drinking alcohol raises your risk of these cancers, as well as cancer of the digestive tract (including colorectal cancer).

Not surprisingly, cancer risk skyrockets in heavy drinkers. According to the NCI, people who drink heavily are five times more likely than nondrinkers to contract esophageal cancer. But, even moderate drinking nearly doubles the odds of mouth and throat cancers, and having as little as one drink a day can increase the risk of breast cancer, too, notes Dr. Jung. Globally, more than 4 percent of all new cases of cancer in 2020 were attributed to alcohol consumption, according to a study published in July 2021 in the journal The Lancet Oncology.

3. Alcohol Changes the Composition of Organisms in the Gut, Which Harms Immunity

Research focusing on the delicate balance of microorganisms that reside in the gastrointestinal tract has found that disruptions to these colonies of bacteria can affect not only digestion but also other aspects of health, particularly immunity. Consuming alcohol has been shown to affect this bacterial balance: Studies have shown that alcoholics have a different balance of gut bacteria, which affects their intestinal barrier, according to a review published in July 2021 in the International Journal of Molecular Sciences. And, chronic drinking has been shown to have harmful effects on immune system cells.

4. Alcohol Affects Long-Term Memory and Brain Structure

One night of binge drinking can lead to blackouts that wipe out memories of key events and details, and consistent alcohol consumption can affect long-term brain function. People who drink heavily over a long period of time are at risk of memory loss, confusion, dementia, and learning issues, among other cognitive problems, reports American Addiction Centers. Heavy alcohol consumption can also raise the risk of stroke and depression, and research published in May 2022 in NeuroImage: Clinical found that even moderate drinking decreases the brain’s gray and white matter. The findings concluded that there is “no safe level of alcohol consumption for brain health.”

5. Alcohol Causes Hormonal Disturbances

Chronic heavy drinking can also wreak havoc on the endocrine system, which acts as one of the body’s main lines of communication between organs and other systems (such as the nervous and immune systems). Similar to the way alcohol creates an imbalance in the gut, it also throws off the endocrine system by disrupting the release of important hormones, creating hormonal disturbances that can permeate every organ and tissue in the body, according to a study published in Alcohol Research. The study reports that the disturbances can go as far as causing reproductive dysfunction, thyroid problems, immune system abnormalities, diabetes, cardiovascular disease, cancer, and psychological and behavioral disorders. Research published in July 2023 in the journal Neurobiology of Stress also found that binge drinking was associated with higher levels of the stress hormone cortisol.