The Age You Sip Your First Drink Could Determine Your Risk for Breast Cancer

Updated: Oct. 10, 2022

Depending on how old you were when you knocked back your first drink—and how you drink now—could dramatically impact your risk of developing breast cancer.

Girl holding a drink - Women holding a drinkMarcel Kriegl/Shutterstock

Most women know they have a one in eight chance of developing breast cancer during their lifetime. Taking every preventive measure possible is one way to lower your risk—and a good place to start is taking a look at your booze intake, according to a report from the American Society of Clinical Oncology. The group lists breast cancer as one of the primary types of cancer directly linked to alcohol consumption.

From a woman’s teenage years to her first pregnancy, her breast cells undergo rapid proliferation, says Heidi Memmel, MD, a breast surgeon and Co-Medical Director of the Caldwell Breast Center at Advocate Lutheran General Hospital in Park Ridge, Illinois. Any potentially cancerous cells are growing at a fast pace and multiplying, making the young adult years a very important time for risk reduction. “Breast cancer risk accumulates across a woman’s lifespan, but the most rapid accumulation occurs around the time a woman has her first period to her first pregnancy,” says Dr. Memmel. Try these five simple habits that reduce your risk of breast cancer.

After pregnancy, a woman’s breast tissue undergoes biologic changes that make the cells more cancer-resistant. This helps explain why women who have children later in life or do not have children at all are at higher risk, says Dr. Memmel. While the link between alcohol and breast cancer isn’t completely clear, she says, the prevailing theory is that alcohol affects circulating estrogen and estrogen receptors in the breast tissue. “The products of alcohol metabolism in the body are also thought to potentially play a role in breast tumor cell growth,” says Dr. Memmel.

 Dr. Memmel says there is a significant increase in breast cancer risk associated with alcohol consumption before age 30, especially if the woman began drinking at an early age. Several studies, such as one published by Ying Liu, MD, a researcher and assistant professor at the Washington University School of Medicine, and colleagues notes that alcohol consumption before a first pregnancy increases risk of breast cancer: “Alcohol is causally related to the risk of breast cancer, with a 7 to 10 percent increased risk for each drink of alcohol consumed daily,” says Dr. Liu.

The age at which a woman begins drinking is only one part of the equation, says Dr. Liu. How she drinks also factors into risk. Binge drinking, which the Centers for Disease Control and Prevention defines for women as having four or more drinks in two hours, is problematic, explains Dr. Memmel: “Women who report seven drinks on the weekend, but no alcoholic drinks during the week have a higher risk than women who have one drink per night,” she says. “Because much youth alcohol consumption is in the form of binge drinking, many young women are unknowingly putting themselves at higher risk of developing breast cancer. It is especially important for young women to know how important a risk factor alcohol consumption is at this stage in their life because it is one of the factors that we can control.”

The CDC reports that one in six adults binge drinks about four times a month. Find out the seven signs you might be binge drinking without realizing it.