Many people use the New Year to reflect on their relationship with alcohol. Just-released government guidance gives Americans another reason to consider Dry January.
Over the past few decades, a growing body of scientific evidence has shown that drinking as little as 1-2 alcoholic drinks per day is associated with an increased risk of many cancers. This prompted U.S. Surgeon General Dr. Vivek Murthy to issue new Surgeon General's Advisory on January 3, 2025, warning of the link between alcohol and cancer. The report highlights the evidence and calls for new cancer warning labels on alcoholic drinks.
The link between alcohol and cancer is nothing new—scientists have been trying to identify the link for decades—but most people are unaware of the risks and may only associate drinking with liver diseases such as cirrhosis . A 2019 survey by the American Institute for Cancer Research showed that less than half of Americans believe alcohol is a risk factor for cancer.
Alcohol is the third leading preventable cause of cancer in the United States, behind tobacco and obesity. As the Health Secretary's report highlights, alcohol is linked to approximately 100,000 cancer cases and 20,000 cancer deaths each year, playing a role in cases of breast, liver, colorectal, oral cavity, throat, esophageal and vocal cord cancers important role. Each year, alcohol-related cancer deaths exceed alcohol-related traffic fatalities.
The report recommends adding warning labels on alcohol similar to those on tobacco products, another substance of abuse known to cause cancer.
As a neuroscientist who specializes in studying the neurobiological effects of drinking and binge drinking, I'm pleased to see calls for action to reduce alcohol consumption in the United States.
Key points of the report
With so few people aware of the link between alcohol consumption and various cancers, and the vast majority of people drinking alcohol on a weekly basis, it's easy to see why the Surgeon General is calling for greater awareness. The 22-page report highlights what scientists know about the relationship between alcohol and cancer and provides recommendations for action moving forward. These include changes to the alcohol label, which has not been updated since its creation in 1988.
Surprisingly, breast cancer accounts for a large proportion of this risk - which is particularly worrisome as women drink more alcohol.
These numbers don't just apply to alcoholics. While drinking less is better, 25% of these cancer cases were among moderate drinkers - an average of less than two drinks per day. This means that anyone who drinks alcohol regularly, even in small amounts, should be informed and aware of the risks.
The Surgeon General's recommendations are the primary way the Department of Health and Human Services, where the Surgeon General's office is located, communicates to the public about very important health issues. The Surgeon General's recommendations are not necessarily breaking news, but they are an opportunity to increase public scientific understanding of a major public health issue.
The science behind the link between alcohol and cancer
Scientists have known about the relationship between alcohol and cancer for decades. In fact, this was highlighted by the 2016 Surgeon General’s report, which looked at addiction more broadly.
The new report outlines the different types of evidence supporting this link. One approach is through epidemiology, which attempts to understand patterns and relationships between cancer rates and how much alcohol people drink. The other is through experimental animal studies, allowing scientists to understand the mechanisms and causation by which these links apply to specific cancers. Overall, the research conclusively shows that there are links and pathways between alcohol consumption and cancer.
The Surgeon General's report highlights four key pathways through which alcohol causes cancer. These focus primarily on the ways in which alcohol negatively affects DNA, the building blocks of cells. Although healthy cells in your body are dividing all the time, abnormal factors such as DNA damage caused by alcohol can cause them to grow abnormally.
This DNA damage causes uncontrolled tissue growth instead of healthy, normal tissue growth. This abnormal tissue growth is cancer. The four ways alcohol causes cancer highlighted in the report are:
The body naturally breaks down alcohol into acetaldehyde. Acetaldehyde can damage and destroy DNA, leading to chromosomal rearrangements and tumors. The connection is so strong that acetaldehyde has been classified as a carcinogen since 1999.
Alcohol produces reactive oxygen species. Reactive oxygen species, sometimes called "free radicals," are unstable molecules containing oxygen that can further damage DNA, proteins and fats.
Alcohol affects hormones such as estrogen. Alcohol can increase the amount of estrogen in the body, which may explain its link to breast cancer. You guessed it, increased estrogen can cause DNA damage, which affects breast tissue.
Alcohol is a solvent, which means other things can dissolve in it. When the two are consumed together, this makes carcinogens from other sources, such as cigarettes and e-cigarettes, more easily absorbed by the body.
Is any amount of alcohol safe?
Probably the biggest question on people's minds right now is "How much alcohol can I safely drink?" The answer may disappoint you—probably not.
Alcohol consumption remains one of the most preventable cancer risk factors. Even moderate drinking (one drink a day or less) may increase the risk of certain types of cancer, such as breast, throat, and oral cancer.
But none of these studies can tell you what your individual risk of cancer is. The relationship between alcohol and cancer may be influenced by genes, such as those that control alcohol-metabolizing enzymes, as well as other lifestyle factors that broadly influence cancer incidence, such as diet and inflammation. All of these lifestyle and personal health factors affect the risks of drinking alcohol to you.
If you choose to drink alcohol, consider sticking to less than one (women) or two (men) standard servings of alcohol per day—it may be less than you think—and avoid binge drinking, the Centers for Disease Control and Prevention says. The surgeon general also recommended reconsidering the guidelines, including updating daily alcohol limits and increasing education around the link between alcohol and cancer.
The National Institute on Alcohol Abuse and Alcoholism has made similar recommendations for limiting drinking, advising those who choose to drink "the less the better."
On its website, the institute offers tips for managing drinking or quitting drinking altogether, including finding other hobbies and activities, identifying what causes urges to drink and developing a plan for dealing with them, and identifying strategies for saying "no" in social situations Drink alcoholic beverages.