7 Cancers Linked to Alcohol Consumption

Breast cancer: Even “a little” might be too much

Breast cancer is the most common form of cancer among women, with roughly 270,000 cases diagnosed annually. Within that massive number is another: About 16 percent, or more than 44,000 cases of breast cancer, are attributed to alcohol consumption, according to a 2024 research review published in the American Cancer Society’s flagship journal CA: A Cancer Journal for Clinicians.

Research consistently finds that alcohol can alter or raise hormone levels, including estrogen. Higher levels of the hormone can lead to mutations in breast tissue that cause cancer. “Even drinking within the guidelines, so one a day for women,” can increase the risk of developing breast cancer, LoConte says.

Put another way, research finds about 11 out of every 100 women who consume less than one alcoholic beverage will develop breast cancer in their lifetime, as noted in the Surgeon General’s advisory. Two more than that, or 13 in every 100 women, who have one drink a day, and 15 in 100 women who have two drinks per day, will develop breast cancer.

Of course, drinking is but one prominent risk factor that could raise a woman’s risk of developing cancer. Many others, starting with age, obesity, genetics/family history and environmental exposures (to radiation, for example), can also stack the deck against a person. Doctors encourage considering all risks.

“If you’re a postmenopausal woman and there is a reason why your risk is higher than normal for breast cancer,” it’s important to factor that in when choosing whether to drink — and how much to drink, says William Dahut, M.D., chief scientific officer for the American Cancer Society.

Mouth, throat and esophageal cancers: The “dose-dependent” dangers of drinking

Although head and neck cancers aren’t as common as breast cancer, the alcohol-related risk of developing these cancers is more pronounced and increases more sharply the more a person drinks.

That risk is present even when a person stays within the recommended limit, which is two drinks per day for men (and, again, one drink per day for women), LoConte says. She recommends abiding by those guidelines at a minimum, “but really getting as low as comfortable” is ideal, she says.

LoConte was the lead author of a 2018 statement on alcohol and cancer by the American Society of Clinical Oncology that outlined those “dose-dependent” relationships between total alcohol consumption and rates for certain cancers.

Heavy drinkers — which the National Institute on Alcohol Abuse and Alcoholism defines as men who consume five or more drinks on any day or 15 drinks or more per week, and women who have four or more drinks on any day or eight or more per week — developed oral cavity (mouth) and pharynx (throat) cancers and esophageal squamous cell carcinoma at around five times the rate of non-drinkers.

A predominant cause of these and other alcohol-related cancers (and a contributor to breast cancer) is a byproduct of the body’s breakdown of alcohol called acetaldehyde, which can damage DNA. Once damaged, cells can grow out of control and turn into tumors.

A mix of risk factors – and a fluid approach to prevention

Other cancer-causing substances and risk factors also mix dangerously with alcohol. As noted in the Surgeon General’s advisory, “carcinogens [a term for cancer-causing substances] from other sources, especially particles of tobacco smoke, can dissolve in alcohol, making it easier for them to be absorbed into the body, increasing the risk for mouth and throat cancers.”

The challenge for public health experts and frustration for social drinkers alike is that there’s no one-size-fits-all recommendation for drinking.

But a general principle holds: “It seems the more you do drink, the greater the risk would be — and factoring that into your individual risk becomes really important,” Dahut says.

That’s true for those who have already been diagnosed with cancer who drink alcohol, too. “It pretty much complicates every step of cancer treatment,” LeConte says, pointing to research on cancer patients who imbibe. “Their surgery stays are longer, they have more surgical complications, they [don’t tolerate] chemotherapy as well, they have higher rates of cancer recurrence.” 

For some time, it’s been known that heavy drinkers have more infections — “evidence of a ‘deranged immune system’ we call it,” LeConte says. “But that may mean immunotherapy, which is potentially curative therapy for many people with cancer — even stage 4 cancer sometimes — will not work as well.”

LeConte understands people don’t make all their decisions based on cancer risk. “But we would like people to at least be aware that alcohol is a carcinogen so that they can incorporate that in their decision-making,” she says.

Editor's note: This story has been updated with new information.