ASCO 2019: Can a Low-Fat Diet Reduce Breast Cancer Mortality?
Posted: Thursday, May 16, 2019
Based on nearly 20-year data from the Women’s Health Initiative trial, to be presented at the upcoming 2019 American Society of Clinical Oncology (ASCO) Annual Meeting (Abstract 520) in Chicago, a low-fat diet consisting of increased vegetable, fruit, and grain intake may significantly reduce the risk of death from breast cancer in postmenopausal women. This randomized clinical trial included of nearly 50,000 women between the ages of 50 and 79 years with no previous breast cancer.
“To our review, these findings provide the first randomized clinical trial evidence that a dietary change can reduce a postmenopausal woman’s risk of dying from breast cancer,” Rowan T. Chlebowski, MD, PhD, of the Los Angeles Biomedical Research Institute, Torrance, California, and colleagues concluded.
The trial was conducted at 40 centers across the United States and included 48,835 postmenopausal women with no history of breast cancer and a dietary fat intake greater than 32% of total energy. Those women were randomly assigned to either a usual diet comparison group or a dietary intervention group, with goals to reduce fat intake to 20% of energy and increase consumption of vegetables, fruit, and grains.
The investigators found that the dietary change significantly reduced fat intake. During the 8.5 years of dietary intervention, patients experienced 8% fewer occurrences and deaths from breast cancer. However, deaths after breast cancer occurrence were significantly reduced with the dietary intervention, both during the intervention (hazard ratio = 0.65) and through cumulative follow-up of median 16.1 years.
After long-term, cumulative median follow-up of 19.6 years, the investigators continued to observe a significant reduction in deaths after breast cancer (1,011 deaths, hazard ratio = 0.85) and a significant reduction in deaths from breast cancer (383 deaths, hazard ratio = 0.79).
Disclosure: The study authors’ disclosure information may be found at coi.asco.org.