Even Small Amounts of Alcohol Can Cause Cancer, Surgeon General Says

On Jan. 3, the U.S. Surgeon General issued a sobering report about the cancer risks linked to something that most Americans enjoy frequently: an alcoholic beverage.

In the advisory, Dr. Vivek Murthy outlined the substantial evidence behind the increased risk of developing seven types of cancers among people who consumed as little as one daily drink, or even fewer.

“What we know with a high degree of confidence is that there is a causal link between alcohol and cancer risk,” says Murthy. “The data has been building for some time and getting stronger and stronger.”

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The advisory cites alcohol as the third leading preventable cause of cancer in the U.S. after tobacco and obesity and notes that there are about 20,000 alcohol-related cancer deaths in the country annually. That’s more than the yearly number of alcohol-associated traffic crash fatalities.

What’s especially concerning, Murthy says, is that 17% of these deaths occur in people who follow the U.S. Dietary Guidelines: consuming no more than two drinks a day for men, and one drink a day for women. One of the recommendations Murthy makes in the advisory is to reassess that advice when the guidelines are revised later this year. “In my mind, this data is concerning and warrants a reduction in the guideline limit [of alcohol consumption],” he says. “This is exactly the kind of data that should be considered when the guidelines are formulated or updated.”

Fewer than half of Americans know that alcohol can increase the risk of certain cancers, despite growing evidence supporting the connection over the past few decades, warnings from major cancer and public-health organizations, and classifications of alcoholic beverages as human carcinogens.

“As a cancer specialist, I am really grateful that the Surgeon General took this action,” says Dr. Ernest Hawk, vice president of cancer prevention at MD Anderson Cancer Center, “and that this message is being shared with the public so they are aware.”

Here’s what to know.

Does this mean that I could get cancer from drinking a glass of wine with dinner?

Overall, people who had one drink a day had a 40% higher risk of developing any of seven types of cancer—mouth, throat, voice box, esophagus, breast, liver, and colorectal—compared to those who didn’t drink at all. The risk was notable for breast cancer: women who consumed one alcoholic drink daily had a 10% higher risk of developing that cancer than those who didn’t drink.

However, any one person’s risk will vary depending on their other behaviors (such as smoking), factors like genetics, and environmental exposures such as pollution or UV radiation. And the more drinks people consumed a day, the higher their risk became.

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Research on alcohol is largely observational; people who drink are compared to those who do not, and their cancer rates are measured over a period of time. Researchers try to account for other factors that could explain for the association between alcohol and cancer, but they may not be able to fully account for these confounding variables.

So while the advisory attributes 100,000 cancer cases in the country each year to alcohol, most cancers can’t be traced back to a single cause. “Can we ever say something is wholly associated with alcohol as opposed to a variety of other things? Probably not,” says Hawk. “But you can, in population-based studies where you’ve tried to account for and mitigate the influence of other variables, see an association between things like alcohol and cancer.”

How solid is the evidence?

In addition to the observational studies in people, animal studies consistently show that alcohol leads to increased risk of cancer.

There are also more detailed studies delving into how alcohol contributes to cancer, including the way in which alcohol is broken down by the body into a compound that can damage DNA in cells, potentially turning them cancerous. Alcohol can also produce harmful oxidation compounds that can trigger inflammation, which can also play a role in cancer formation.

Another theory involves alcohol’s ability to change the balance of hormones, including estrogen, which is implicated in breast cancer. It’s also possible that other cancer-causing agents such as tobacco can be more easily absorbed and dissolved in alcohol, accelerating their carcinogenic effects on the body.

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“The message regarding cancer is very clear: alcohol increases the risk of cancer across several sites [in the body] in a convincing manner,” says Hawk. “Alcohol is one of the leading modifiable cancer risks.”

“From a strictly cancer perspective, there is no safe amount of alcohol,” says Dr. Noelle LoConte, associate professor of hematology, medical oncology, and palliative care at the University of Wisconsin who authored the American Society of Clinical Oncology’s policy statement on alcohol and cancer.

The group recognizes, however, that people have differing underlying risks for cancer and therefore supports the current recommendation that most men limit themselves to no more than two drinks a day and most women consume no more than one.

I thought drinking red wine protected my heart.

Alcohol’s link to cancer was the sole focus of the current advisory. Its link to heart health is somewhat more complicated—but science there is changing, too.

In 1996, the American Heart Association issued an advisory that sent quite a different message about alcohol. It noted that studies showed a 30% to 50% lower risk of heart-related events among people who drank up to two drinks daily compared to those who abstained.

But additional research with more stringent control groups and better trial designs in recent years have questioned the potential heart benefits of alcohol, with the latest showing that even a daily drink can increase blood pressure, a risk factor for heart disease.

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“The relation between alcohol and coronary heart disease is complex,” said the American Heart Association in a statement to TIME. “Risks and benefits of drinking alcohol vary depending on many factors. The American Heart Association looks forward to reviewing the reports that will inform the 2025 U.S. Dietary Guidelines in depth.”

The American Heart Association currently advises people to not start drinking if they don’t already, and if they do enjoy imbibing, to limit themselves to two drinks a day for men and one drink a day for women.

Will the Surgeon General’s advisory change alcohol labels?

Murthy is calling for all alcoholic beverages to carry a warning label, similar to the one that currently calls out the risk of birth defects for pregnant women who drink.

Nearly 50 countries require warnings about the health risks of alcohol, according to the advisory, but only South Korea and Ireland mention cancer specifically, with Ireland’s new warnings expected to start appearing in 2026.

Many cancer experts support a new warning label, noting that while the evidence of alcohol’s risks have been growing in recent decades, most people aren’t aware of the connection. “We’re not here to take us back to prohibition; we just want people to be aware of the risk so they can act on it as it suits them best,” Hawk says.

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The U.S.’s cultural and public-health evolution concerning tobacco and smoking could serve as a useful precedent for changing how we think about alcohol and its associated health risks. Congress will need to require adding the warning, as it did for tobacco products after the Surgeon General’s warning in the 1960s. “In terms of the scientific data, there is enough to support a warning label,” says Jennifer Hay, attending psychologist and behavioral scientist at Memorial Sloan Kettering Cancer Center. The question is: “How important is this to Congress?” Hay says. “And what kind of evidence are they going to want to see in order to move ahead with a warning label?”

Raising awareness about the risks of alcohol is just the first step, she says, and will require cultural shifts as well. Alcohol is an ingrained part of how we celebrate and define social enjoyment, but that could change. “People smoked in restaurants, people smoked at the movies; people smoked everywhere,” says Hay. “It looked cool, it looked sophisticated, but things changed slowly.”

“It will take time,” she says. “But if we use what happened with tobacco as a cultural touchpoint for what the country is able to do, it shows that we are teachable.”