Experts Warn Binge Drinking Drives Early-Onset Breast Cancer, While Cessation Reduces Risk

Alcohol increases breast cancer risk, with binge drinking particularly driving early-onset cases, underscoring the need for public education, clinical intervention, and further research, experts said during yesterday’s special session, “Open Bar and All You Can Eat? The Impact of Lifestyle in Breast Cancer Risk and Recurrence,” which helped kick off this year’s San Antonio Breast Cancer Symposium (SABCS).1

Experts at SABCS 2025 said alcohol consumption raises breast cancer risk, emphasizing the need for public education and clinical intervention.| Image credit: BillionPhotos.com - stock.adobe.com

From Early Studies to Modern Understanding of Alcohol, Breast Cancer

Before his term ended on January 20, then–Surgeon General Vivek Murthy, MD, MBA, called for alcohol labels to include cancer warnings, noting links to at least 7 types: oral cavity, pharynx, larynx, esophagus, colorectum, liver, and breast.2 Despite the recent attention on the connection between alcohol and cancer, Julia R. Palmer, ScD, MPH, of Boston University, highlighted in her presentation, “Alcohol, Genetics of Alcohol Metabolism, and Breast Cancer Risk,” that the first evidence linking the two emerged in 1977 from a study by William and Horm, which included breast cancer among several associated cancers.3

A second study published 5 years later built on this work by controlling for known and suspected breast cancer risk factors and using 2 different control groups.4 It found that women who consumed 4 or more drinks per week were estimated to have more than twice the risk of breast cancer than those who drank very little or not at all.

Palmer noted that an influx of research followed over the next 5 to 10 years, with the most impactful being the 1987 prospective Nurses Health Study published in the New England Journal of Medicine.5 It reported a small increased breast cancer risk for women consuming about 1 drink per day and a higher risk for those drinking more than 1 daily or over 7 per week. This study, she said, caused researchers to pay closer attention to the relationship between alcohol and breast cancer.1

Today, the preponderance of evidence indicates alcohol as a risk factor for breast cancer, with risk increasing alongside consumption.

“By now, there have been studies done in many other countries, pretty much all parts of the world,” Palmer said. “Results aren’t completely consistent, but almost all of the studies find that women who drink at least a drink a day, or maybe a little bit less, have an increased risk of breast cancer, so across all populations.”

She further examined how different patient factors influence risk, including drinking patterns. Even very light drinking was found to increase risk, though Palmer noted that self-reported intake often underestimates true consumption, potentially skewing results. Binge drinking, defined as drinking 6 or more drinks in a day or a large quantity at least once a month, also increases risk, even after women take control of their drinking habits.

Contrary to past beliefs, the type of alcoholic beverage consumed does not affect risk, and the relationship is observed in both pre- and postmenopausal women. As for breast cancer type, Palmer noted alcohol consumption to be more strongly linked with estrogen receptor–positive disease.

She concluded by highlighting the potential genetic factors of this connection. Palmer explained that alcohol is primarily metabolized by alcohol dehydrogenase into acetaldehyde, a carcinogen. Genetic variants influence how quickly alcohol is metabolized, namely ADH1C, which is common globally, and ADH1B, found mostly in Asian populations.

Although these variants affect alcohol metabolism, studies indicate they have minimal impact on breast cancer risk. Instead, Palmer highlighted that alcohol’s effect could likely be driven more by hormonal changes, as it increases circulating female hormones and androgens, with more research needed.

The Impact of Alcohol Cessation, Reduction on Breast Cancer Risk

Mary Beth Terry, PhD, of the Columbia University Mailman School of Public Health, built on Palmer’s presentation with her own, “Effects of Alcohol Consumption and Cessation on Breast Cancer Risk,” exploring whether stopping or reducing alcohol consumption lowers breast cancer risk. She noted that she was first invited to speak on this relationship at SABCS 7 or 8 years ago, at a time she assumed the connection was widely known, but it remains an important topic that is still not well understood today.

Terry focused on what happens to breast cancer risk if someone stops drinking. Of the hundreds of studies on breast cancer and alcohol, only 21 addressed cessation or reduction, with evidence being limited due to inconsistencies in cohort studies and the limited biological data.6 However, available studies indicate that stopping alcohol consumption completely reduces the risk of hormone receptor–positive breast cancers.

She emphasized that there are fewer epidemiological studies on alcohol cessation than smoking cessation, partly due to cultural bias, yet they remain essential.1

“…we don’t really think people stop drinking or reduce drinking unless they’re of that tail of the distribution that has alcohol use disorder,” she said. “Well, I would argue that these kinds of questions are coming up more and more, and especially when we’re looking at early-onset cancer, we need to be asking these questions about patterns of use, reduction of use, and cessation of use.”

Terry underscored that sufficient data existed to establish this association decades ago via meta-analysis. Still, the evidence went largely untranslated since it was not a clinical trial, leaving many patients unaware of alcohol’s link to breast cancer. She noted that the delay in understanding is partly due to superficial clinical assessments, with physicians often labeling patients as “social drinkers” without meaningful discussion, and the widespread underreporting of alcohol consumption, as highlighted by Palmer earlier.

Research comparisons have also been flawed historically, Terry added, often using nondrinkers as a reference group, which mixes never-drinkers with “sick quitters,” including past binge drinkers with hard-to-reverse effects. Additionally, mechanistic studies on cessation are extremely limited, mostly focusing on men with alcohol use disorders, leaving key questions, such as how stopping alcohol consumption affects women’s hormone levels, unanswered.

Additionally, early-onset cancers disproportionately affect women, with two-thirds of cancers diagnosed under age 50 in the US and globally being in women, most frequently breast cancer, followed by thyroid cancer. Although alcohol is not the only factor, Terry emphasized the importance of acknowledging its role, particularly binge drinking. US data show that binge drinking, independent of regular alcohol consumption, strongly predicts these early-onset trends in patients diagnosed with breast cancer under age 40.7

To address alcohol-related cancer risk, she suggested using counter-marketing strategies like those used in successful antismoking campaigns, emphasizing education for young people about the dangers of alcohol, particularly before age 25.1 Terry highlighted the role of clinicians in prevention, noting their “incredible power” to discuss the dangers of alcohol, especially binge drinking, with patients.

She concluded by underscoring that stopping alcohol use reduces breast cancer risk, though evidence on the impact of limiting intake remains limited. Particularly, Terry stressed the need to inform the public about the relationship between binge drinking and cancer risk.

“I do think, as public health practitioners, we have enough data now to say, independent of regular alcohol drinking, binge drinking is separate,” she said. “We should definitely start promoting intervention studies to find people, identify people, and get them into care who admit to binge drinking.”

References

1. Khan SA, Palmer JR, Terry MB, Brown KA, Tinianov S. Open bar and all you can eat? the impact of lifestyle in breast cancer risk and recurrence. Presented at: San Antonio Breast Cancer Symposium 2025; December 9-12, 2025; San Antonio, TX.
2. Shaw ML. Alcohol and cancer: Murthy’s urgent call. AJMC. January 6, 2025. Accessed December 9, 2025. https://www.ajmc.com/view/alcohol-and-cancer-murthy-s-urgent-call
3. Williams RR, Horm JW. Association of cancer sites with tobacco and alcohol consumption and socioeconomic status of patients: interview study from the Third National Cancer Survey. J Natl Cancer Inst. 1977;58(3):525-547. doi:10.1093/jnci/58.3.525
4. Rosenberg L, Slone D, Shapiro S, et al. Breast cancer and alcoholic-beverage consumption. Lancet. 1982;1(8266):267-270. doi:10.1016/s0140-6736(82)90987-4
5. Willett WC, Stampfer MJ, Colditz GA, Rosner BA, Hennekens CH, Speizer FE. Moderate alcohol consumption and the risk of breast cancer. N Engl J Med. 1987;316(19):1174-1180. doi:10.1056/NEJM198705073161902
6. Gapstur SM, Bouvard V, Nethan ST, et al. The IARC perspective on alcohol reduction or cessation and cancer risk. N Engl J Med. 2023;389(26):2486-2494. doi:10.1056/NEJMsr2306723
7. Chen J, Kehm R, Yang W, Terry MB. Increasing rates of early-onset Luminal A breast cancers correlate with binge drinking patterns. Breast Cancer Res. 2024;26(1):145. doi:10.1186/s13058-024-01894-7