Diet Double In Fruits, Vegetables Does Not Prevent Breast Cancer Recurrence, National Study Finds
- Created on March 1st, 2008
- By The Center for Research on Minority Health
An extremely low-fat diet rich in fruits, vegetables and fiber neither reduces the risk of breast cancer recurrence in women, nor increases the chance for survival any more than the nationally recommended "5-a-day," according to a pivotal study published in the July 18 issue of the Journal of the American Medical Association.
The largest and most comprehensive diet prevention study ever conducted, The Women's Healthy Eating Living (WHEL) was supported by the National Cancer Institute and enrolled 3,088 women previously treated for early stage breast cancer. Seven institutions across the country participated in the study, with the Moores Cancer Center at the University of California, San Diego serving as the coordinating site.
The University of Texas M. D. Anderson Cancer Center enrolled 380 breast cancer survivors, including approximately 50 percent (50) of the African American who participated in the study, with total minority participation being approximately 25%. Lovell Jones, Ph.D., professor & director of the Center for Research on Minority Health (CRMH) in the Department of Heath Disparities Center, says the study's results were extremely surprising. It should be noted that the CRMH is one of NIH/NCMHD's Centers of Excellence.
"The WHEL's findings are pivotal because we always assumed that we were not eating enough fruits and vegetables and the more we ate, the more protected we would be against cancer," says Jones, the study's principal investigator at M. D. Anderson.
"Earlier observational studies of the WHEL's own control group saw a 40 percent increase in survival. Additionally, a report of interim analysis from the Women's Intervention Nutrition Study found that a low fat diet might reduce the risk of recurrence. Given these findings, we really did think that we would see a significant statistical difference in the recurrence and survival rates between the women who adopted a super healthy lifestyle compared to those that ate the recommended allowance."
The 10-year randomized trial enrolled participants between 1995 and 2000; all of the patients were 18-70 years old and survivors of early stage breast cancer, up to Stage IIIA. The comparison group (1551 women) followed the "five-a-day" healthy diet, were given written material regarding a healthy lifestyle, offered four cooking classes during the first year and received bimonthly newsletters. In contrast, the intervention group (1537 women) adopted a diet double in vegetable and fruit daily servings, high in fiber and low in fat. They were intensively monitored with frequent phone counseling sessions, were offered 12 cooking classes during the first year and received monthly newsletters.
There was a 90 percent compliance rate in the study and the women in the intervention group averaged an intake of nine servings of fruits and vegetable a day, both very impressive statistics, says Jones. The study's primary endpoints were combined outcome of breast cancer recurrence or a new primary cancer diagnosis and death from any cause. The women were followed for 7.3 years.
There was no statistical difference in either the recurrence or death rates in the two groups. During the study, 518 of the women.