What We Know About Alcohol and Other Risk Factors

by Annette Pinder 

Breast cancer deaths have declined dramatically over the past several decades, thanks to earlier detection and better treatments. Yet there is a troubling trend: more women are being diagnosed with the disease. 

According to the American Cancer Society (ACS), breast cancer incidence among U.S. women has been increasing by about 1% annually in recent years. The increase has been somewhat greater among women younger than 50, at about 1.4% per year. 

There is no single explanation. Researchers point to a combination of factors, including excess body weight, having fewer children, having a first child later in life, hormonal and reproductive factors, and lifestyle. One established risk factor that often receives less attention is alcohol. 

Alcohol and Breast Cancer

The connection between alcohol and breast cancer is not new, but many people remain unaware of it. The National Cancer Institute (NCI) says there is strong scientific evidence that drinking alcohol causes several cancers, including breast cancer.  

And heavy drinking is not required to increase risk. Women who average just one alcoholic drink a day have a higher risk of breast cancer than women who drink less than one drink a week. NCI estimates that breast cancer risk increases approximately 7% for each additional alcoholic drink consumed per day. 

Why? When the body breaks down alcohol, it produces acetaldehyde, a toxic chemical that can damage DNA. Alcohol can also create oxidative stress, interfere with the body’s ability to absorb certain nutrients, and increase blood levels of estrogen. Higher estrogen levels are associated with increased risk of some breast cancers. 

Beer, wine, and liquor all contain ethanol, so switching from one type of alcoholic beverage to another does not eliminate the risk. Despite its reputation for possible health benefits, red wine has not been shown to protect against cancer. 

Risk Is Bigger Than One Behavior

Alcohol should not be viewed as the explanation for rising breast cancer rates. Age, genetics, family history, breast density, reproductive history, physical activity, body weight after menopause, and hormone exposure can all influence risk. Some can be changed; others cannot. However, there is encouraging news. Breast cancer mortality has fallen dramatically. ACS reports that death rates declined 44% between 1989 and 2023, largely because of improvements in screening, awareness, and treatment. 

For Breast Cancer Awareness Month, the message isn’t that women should fear everything they eat, drink, or do. Instead, awareness provides an opportunity to make informed choices. Women can talk with their healthcare providers about their individual breast cancer risk, appropriate screening, maintaining a healthy weight, staying physically active, and alcohol consumption. For women who drink, drinking less is one step that may help lower cancer risk.