Women who have a genetic predisposition for breast cancer can lower their risk of developing the disease by following a healthy lifestyle, state researchers at the Johns Hopkins Bloomberg School of Public Health in Baltimore. Using records from more than 40,000 women tested for the gene variant associated with breast cancer risk, the researchers created a “model” for predicting a woman’s risk. They found that the average 30-year-old white woman has an 11% chance of developing breast cancer by age 80-years-old. Some women have a higher risk because of other gene variations, but lifestyle choices made the biggest difference in risk. The lifestyle choices that had the greatest protective effect against breast cancer were: 1) maintaining a healthy weight, 2) not smoking, 3) limiting alcohol, and 4) not using hormone therapy after menopause. The researchers estimated that if all white women followed those four rules, 30% of breast cancer cases would be avoided, and the majority of those cases would be among women at increased risk because of family history and the gene variants they carry. Even women with the highest risk could reduced their odds of breast cancer to an average risk.
Maas P, Barrdahl M, Joshi A, et al: Breast cancer risk from modifiable and nonmodifiable risk factors among white women in the United States. Journal of the American Medical Association: Oncology 2016; May 26th.