Alcohol and Breast Cancer Risk

While the association between alcohol consumption and breast cancer is not as strong with other risk factors, there is a definite link. In fact, the more alcohol you drink, the greater your risk of developing the disease—and having a more aggressive type of breast cancer.

There are not many effective methods of reducing your breast cancer risk, and cutting back on alcohol is one of the important ways to decrease your chances of developing the disease, especially if you are at high risk for breast cancer.

The Link Between Alcohol and Breast Cancer

Alcohol is not the leading risk factor for breast cancer. In addition, drinking is more closely tied to a number of other illnesses than it is to breast cancer. That doesn't mean that it can't play a notable role.

Binge drinking (five or more standard alcohol drinks within a two-hour period for males; four or more for females) and/or heavy drinking (four or more drinks/day or 14 or more drinks/week for men; three or more drinks/day or more than seven drinks/week for women), especially at a young age, increase the chance of developing breast cancer later in life. Heavy drinking also affects the risk of breast cancer in postmenopausal women.

But moderate drinkers are not off the hook: 18% of alcohol-related breast cancers are associated with light alcohol consumption (10 grams of alcohol per day).

Alcohol affects females differently than it affects males, often resulting in more serious health consequences for women. However, while alcohol is associated with about 8% of newly diagnosed breast cancers and about 7% of breast cancer deaths overall, in men specifically, it is associated with 16% of breast cancers.

Tumor Type and Grade

Alcohol consumption is associated with more aggressive, fast-growing tumors (i.e, high-grade tumors).

Cases are also more likely to be of the hormone receptor-positive type, which can be treated with certain hormone inhibitors.

How Alcohol Raises Breast Cancer Risk

Alcohol increases the risk of several medical illnesses (such as liver disease, neuropathy, and dementia), as well as many types of cancer (such as pancreatic cancer, liver cancer, and stomach cancer).

According to the U.S Department of Health and Human Services, alcoholic beverages are considered to be carcinogens (cancer-causing agents). In addition to causing cancer, alcohol facilitates cancer growth when cancer has already started. 

Alcohol promotes the initiation and growth of cancer through several mechanisms, including:

• Liver disease: Alcohol often leads to liver failure. The liver is involved with many physiological functions, including maintaining healthy immunity. Because the immune system helps fight cancer, liver impairment can give cancer a greater chance of enlarging and spreading.
• Oxidative stress: Alcohol metabolism increases oxidative stress, a byproduct of normal metabolism that induces damage to DNA, which can initiate cancer.
• Breakdown of tissue: Alcohol consumption results in toxic byproducts that break down tissues throughout the body. If a person has cancer, the breakdown of epithelial tissue (tissue that lines the body) facilitates metastasis (spread) of cancer.

In addition to these general carcinogenic effects, alcohol raises the risk of breast cancer specifically by increasing estrogen levels, especially estradiol and estrone. Higher estrogen levels elevate the risk of breast cancer, and chronic or irregular exposure to elevated estrogen can have a lasting effect on breast cancer risk, increasing the chances of developing the disease years down the road.

A Word From Verywell

Keep in mind that there are other important modifiable risk factors for breast cancer, including smoking cessation, avoiding artificial additives in your food, and maintaining a healthy weight. All types of cancer, including breast cancer, develop in response to a combination of factors—alcohol is just one.