Obesity Genes Raise Risk of Death After Breast Cancer – But Walking Can Lower the Odds
A new study reveals breast cancer survivors with a genetic predisposition to obesity face a higher risk of early death, but researchers say regular walking can significantly reduce that risk.
The research, led by Clara Bodelon, PhD, a senior principal scientist at the American Cancer Society, focused on how genetic factors influencing weight impact mortality among breast cancer survivors. “There are ways to offset the genetic contribution to mortality risk by adding additional steps,” Bodelon says.
Researchers Analyzed Hundreds of Genetic Markers
Previous research has established that women with obesity or who are overweight have a higher risk of dying from breast cancer. This study investigated whether a genetic tendency toward excess weight further increases that risk.
Researchers followed over 4,000 postmenopausal women in their sixties and seventies diagnosed with early-stage breast cancer between 1992 and 2017. Participants, part of the American Cancer Society’s Cancer Prevention Study II Nutrition Cohort, were tracked for an average of 15 years.
The team estimated genetic risk for higher body weight by analyzing DNA samples and calculating a polygenic score based on over 900 genetic markers previously linked to body mass index. women were then divided into groups based on their genetic score: high, medium, and low risk.
Women with a high genetic risk for carrying extra weight were more likely to be obese at the time of their breast cancer diagnosis, though genetics weren’t a perfect predictor of body size. Over 40 percent of women in the high genetic risk group had a body mass index (BMI)