While breast cancer risk factors like genetic predisposition and excess weight have been studied at length, researchers are gathering new evidence on how they impact a woman's chances of surviving the disease.
According to research presented at the Fifth AACR Conference on The Science of Cancer Health Disparities in San Diego this week, weight -- and more specifically, an extreme body mass index or high waist-to-hip ratio -- was shown to increase risk for mortality among patients with breast cancer, experts say. But the association varied by race/ethnicity.
In a study of data from 12,025 female patients with breast cancer from the California Breast Cancer Survivorship Consortium, research scientist Marilyn L. Kwan discovered that among non-Latina white women, being underweight or morbidly obese at the time of a breast cancer diagnosis was associated with worse survival. The relationship was not found in the other racial/ethnic groups, however.
For other groups, including African Americans, Kwan and her team honed in on another form of excess weight instead -- abdominal fat. “African-American women and Asian-American women with larger waist-to-hip ratios had poorer survival, an observation not seen in non-Latina white women and Latina women,” Kwan said in a release.
While researchers have known the danger abdominal fat poses to breast cancer patients for some time (a team at UNC also made the link back in 2006), it's the racial and ethnic disparity that Kwan points out as new. Her research joins a growing body of evidence suggesting that breast cancer recommendations and treatment should be more personalized.
According to the Mayo Clinic, a waist measurement of 35 inches (89 centimeters) or more indicates an unhealthy concentration of belly fat in women and a greater risk of problems, including breast cancer, diabetes and heart disease.
To trim it (especially the dangerous visceral variety), doctors recommend a portion-controlled, plant-based diet that is low in saturated fat, along with at least 150 minutes of moderate to vigorous aerobic activity per week. For long-lasting results, aim for a slow and steady weight loss of up to 2 pounds (1 kilogram) a week and forgo crunches or other targeted abdominal exercises, which experts say won't get rid of belly fat.