The US Surgeon General said on Friday that alcohol is a major preventable cause of cancer, and that alcoholic beverages should carry a warning label like packs of cigarettes do.
It’s the latest salvo in a heated debate over the risks and benefits of moderate drinking, as the influential US Dietary Guidelines for Americans are about to be updated. For decades, drinking alcohol in moderation has been said to help prevent heart attacks and strokes.
This perception has been included in the nutritional advice given to Americans. But growing research has linked drinking alcohol, even sometimes within recommended limits, to various types of cancer.
Labels currently affixed to bottles and cans of alcoholic beverages warn against drinking alcohol during pregnancy or before driving and operating other machinery, and about general “health risks.”
Surgeon General Dr Vivek Murthy said alcohol directly contributes to 100,000 cancer cases and 20,000 cancer-related deaths every year.
he He called for updating the nomenclature To include an increased risk of breast cancer, colon cancer, and at least five other malignant tumors now linked through scientific studies to alcohol consumption.
“Many people assume that as long as they drink at or below the current guidelines of one drink a day for women and two for men, there is no risk to their health or well-being.” Murthy said in an interview.
“The data doesn’t hold that true for cancer risk.”
Only Congress can impose new warning labels of the kind recommended by Dr. Murthy, and it is not clear whether the incoming administration will support such a change.
However, President-elect Donald J. Trump does not drink, and Robert F. Kennedy Jr., his pick to head the Department of Health and Human Services, swore off alcohol and drugs decades ago, and says he regularly attends AA meetings.
There is no doubt that heavy consumption is harmful. But proponents of moderate drinking — including wine, beer and spirits makers, and some doctors and scientists — argue that drinking a little alcohol each day may reduce cardiovascular disease, the No. 1 killer in the United States.
However, recent scientific studies have criticized the methodology of previous studies and challenged this view, which was previously a consensus.
While most cancer deaths occur at drinking levels that exceed current recommended dietary guidelines, the risk of breast, mouth and throat cancer may rise with just one drink a day, or even fewer, Murthy said. Friday.
Overall, one in six breast cancer cases is attributed to alcohol consumption, Dr. Murthy said. More recent studies have also linked moderate alcohol consumption to certain forms of heart disease, including atrial fibrillation and irregular heartbeat.
Two scientific reviews will be used to inform updated recommendations about alcohol consumption in the federal dietary guidelines.
five years ago, Scientific report Which informed the writing of the 2020-2025 dietary guidelines recognized that alcohol is a carcinogen and generally unhealthy and suggested ‘Tighten guidelines’ By setting a maximum recommendation for men at One standard drinkOr 14 grams of alcohol per day.
However, when the final guidelines were drafted, there was no change to the advice that moderate drinking of up to two drinks a day for men was acceptable.
But the government acknowledged emerging evidence that “even drinking within recommended limits may increase the overall risk of death from various causes, such as several types of cancer and some forms of cardiovascular disease.”
Since then, more studies have linked alcoholic beverages to cancer. However, any attempt to change warning labels on alcoholic beverages is likely to face an uphill battle.
The current warning label has not been changed since its adoption in 1988, although the link between alcohol and breast cancer has been known for decades.
It was first mentioned in the 2000 US Dietary Guidelines. In 2016, the Surgeon General’s Report on Alcohol, Drugs, and Health linked alcohol misuse to seven different types of cancer.
More recently, Congress commissioned a scientific review of research on moderate alcohol use, conducted under the auspices of the National Academies of Sciences, Engineering, and Medicine.
This analysis found a link between alcohol consumption and a small increase in breast cancer, but no clear link to any other cancers. The report also revived the theory that moderate drinking is associated with fewer deaths from heart attacks and strokes, and fewer deaths overall, than not drinking at all.
The World Health Organization says there is no safe limit for alcohol consumption, and 47 countries require warnings about alcoholic beverages. But cancer is rarely mentioned.
So far, only South Korea has a warning label about liver cancer, although manufacturers can choose alternative labels that do not mention cancer. Ireland is currently due to introduce posters saying there is a “direct link between alcohol and fatal cancers” in 2026.
The industry has a strong history of combating cancer warning labels, and alcohol-producing countries have also challenged warning labels under international trade law.
Industry opposition has led to the early termination of a federally funded Canadian study on the impact of cancer warning labels.
The Surgeon General’s advice provided a brief overview of research studies and reviews published in the past two decades, including a global study of 195 countries and territories that included 28 million people.
They all found that higher levels of alcohol consumption were associated with an increased risk of cancer.
Other studies looked at specific types of cancer, e.g breast cancer and mouth cancer, It found that the risks increased by 10% and 40%, respectively, for those who had just one drink a day, compared to those who did not drink.
The report described the biological mechanisms by which alcohol is known to cause cancerous changes at the cellular level.
The most widely accepted theory is that alcohol breaks down within the body into acetaldehyde, a metabolite that binds to and destroys DNA, allowing the cell to begin growing uncontrollably and creating a malignant tumor.
Animal experiments showed that rodents whose drinking water was laced with either ethanol, alcohol used in alcoholic beverages, or acetaldehyde developed large numbers of tumors throughout their bodies.
Research has shown that alcohol generates oxidative stress, which increases inflammation and can lead to DNA damage.
It also changes hormone levels such as estrogen, which can play a role in the development of breast cancer, and facilitates the absorption of carcinogens such as tobacco smoke particles into the body, which increases susceptibility to mouth and throat cancer.
The Surgeon General’s report also goes into detail about the increases in risks associated with drinking, differentiating between increases in absolute risks and relative risks.
For example, the absolute risk of developing breast cancer over a woman’s lifetime is about 11.3 percent (11 in 100) for those who have less than one drink per week.
The risk increases to 13.1% (13 out of 100) for one drink per day, and up to 15.3% (15 out of 100) for two drinks per day.
For men, the absolute risk of alcohol-related cancer increases from about 10 percent (10 per 100 people) for those who consume less than one drink per week to 11.4 percent (11 per 100 people) for those who drink one drink every week. A day on average. It rises to 13 percent (13 out of 100 people) for those who drink two drinks a day on average.
Many Americans do not know that there is a link between alcohol and cancer.
Less than half of Americans They identified alcohol use as a risk factor for cancer, compared to 89% who considered tobacco a carcinogen, according to a 2019 American Institute for Cancer Research survey of American adults ages 18 and older.
However, alcohol consumption is the third leading preventable cause of cancer, after tobacco and obesity, according to the Surgeon General’s report.
Dr. Murthy said it is important to know that the risk increases with increased alcohol consumption. But the risk of cancer varies from person to person, depending on family history, genetic makeup and environmental exposure.
“I wish we had a magic bullet that we could tell people it’s safe,” he said. “What we know is that less is more when it comes to reducing your risk of cancer.”
He added: “If an individual drinks occasionally on special occasions, or if you have one or two drinks a week, your risk is likely to be much lower than if you drink every day.”