African-American women who consume seven or more alcoholic beverages per week have an increased risk of developing breast cancer, according to new research.

Results of a study showed women who drank seven or more drinks per week showed a higher risk of nearly all of the subtypes of breast cancer. Those who drank 14 or more drinks per week were 33 percent more likely to develop breast cancer than women who were light drinkers and consumed four or fewer alcoholic beverages per week.

The study, published in Cancer Epidemiology, Biomarkers & Prevention, includes data from 22,338  women from the African American Breast Cancer Epidemiology and Risk (AMBER) Consortium. The participants self-reported their alcohol intake via a questionnaire, and researchers used a statistical method to determine the association between the number of alcoholic beverages they drank and cases of breast cancer. There were 5,108 cases of breast cancer among the women involved in the study.

Previous studies indicate white women have the same risk, but the researchers were interested in seeing if this held true for African-Americans, as this population is largely understudied, in regards to the association between breast cancer and alcohol consumption.

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Overall, black women drink less alcohol than white women, study author Melissa Troester, noted in a press release. In the study, nearly half of the women indicated they didn’t consume alcohol, and Troester and her team found “never drinkers” were more likely to develop breast cancer than the light drinkers. Although the researchers did not indicate why the women who didn’t drink had an increased risk of cancer, prior research has found similar elevated risks, and has shown other diseases, such as diabetes, led them to avoid alcohol.

Unlike other risk factors for breast cancer, people can avoid drinking alcohol, and “reduced intake among African American women should be encouraged,” the authors note in their paper. According to the American Cancer Society, some breast cancer risk factors you cannot change include getting older, certain inherited genes, having dense breast tissue, and having a personal or family history of breast cancer.

Troester said future studies are necessary to understand how breast cancer risks, such as weight or oral contraceptive use, impact each race differently.

"Understanding the impact of these various risk factors could help narrow the disparity in breast cancer incidence and mortality," she said.

Prior findings have clearly linked alcohol consumption to an increased risk of developing breast cancer. Heavy drinking has also been identified as increasing the risk of other types of cancer, the American Cancer Society states.

Not including certain types of skin cancer, breast cancer in the United States is the most common cancer in women, regardless of race or ethnicity, according to the Centers for Disease Control and Prevention. It’s also the second most common cause of death from cancer among white, black, and Asian/Pacific Islander women; lung cancer is the first.

 

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