Erroneous messages on diet and breast cancer with potentially life threatening consequences

Recent media reports are suggesting that a diet high in fruits and vegetables and low in fat has no notable impact on breast cancer recurrence or death.

Internationally recognized integrative cancer care specialist Keith Block, MD, is advising breast cancer survivors to pay no heed to these stories.

“The news reports that condense findings from the Women's Healthy Eating and Living (WHEL) breast cancer study into attention-grabbing sound bites have missed the point about the connection between healthy eating and preventing breast cancer recurrence,” says Dr. Block, medical director at the Block Center for Integrative Cancer Treatment. “The public is getting erroneous messages with potentially life threatening consequences. The headlines from this six year study: ‘Diet Found Not to Help Breast Cancer Survival,' and ‘Healthiest Diet Made Little Difference to Breast Cancer Survivors,' are not only misleading, they misrepresent the study's findings.”

A close look at the study explains this discrepancy. The investigators' goal was to get the intervention group to reduce their fat intake to 15%- 20% of their total caloric intake, and increase their fruit and vegetable consumption. While fruit and vegetable consumption was increased, study participants never came close to reaching the desired goal for fat intake. Initially, the fat intake did drop in the direction of the intended goal; however, the problem is that by year 4, the average intake was greater than 27%, and by year 6, the participants averaged 29% of their daily calories from fat. Even the most conservative researchers will agree that this level of intake is too high to be called a “low-fat diet.” Thus, the suggestion that the recommended diet didn't work is unjustified. “The proposed intervention wasn't even tested, perhaps because the telephone counseling system used to instruct patients in the diet was ineffective in the long run. It is therefore impossible to conclude from the WHEL study that diet doesn't help prevent breast cancer recurrence,” notes Block.

Countering the misleading headlines from the WHEL study is the Women's Intervention Nutrition Study (WINS). In this study, women who received in-person counseling were successful in cutting their fat intake to 20% or less, and maintained this level for the entire 5 years of the study. This reduction in fat intake demonstrated an impressive 24% decline in breast cancer recurrence! Among women who lacked estrogen receptors (referred to as estrogen negative), the low-fat diet was even more effective. This group showed a 42% reduction in breast cancer recurrence.

According to Block, another analysis of the WHEL study has also been left out of most of the headlines. The WHEL investigators also looked at data from the women in the control group. These women not only ate 5 servings a day of vegetables and fruits, but also exercised at least 30 minutes a day, 6 days a week. They had half the mortality rate of those who either ate fewer servings of vegetables and fruits, or exercised less. “This is a truly exciting result, and one that puts the findings of both the WHEL and the WINS study into a different perspective,” reports Block. What is the takeaway message? According to Block, “I continue to tell my breast cancer patients that diet is crucial as one component of care. At the Block Center, we believe that careful, long term monitoring is necessary to individualize therapeutic interventions for each patient. There are dietary strategies, however, that are appropriate for all of our patients.” These include:

• Eat a diet lower in fat, ideally no more than 18% of your daily caloric intake. Use “good” fats -- monounsaturated and omega-3 fats – from olive oil, flax seed oil, almond oil and canola oil, as well as fats from deep-sea fish.
• Eat cruciferous vegetables, such as broccoli, bok choy, and brussel sprouts – which contain plant phytochemicals that lower blood estrogen levels by increasing the estrogen detoxification capacity of the liver.
• Eat a diet high in fiber, with plant-based sources of protein. Fiber from whole grains, vegetables, fruit, and beans can reduce harmful circulating estrogen levels.

The Block Center for Integrative Cancer Treatment, located in Evanston, Illinois, was founded in 1980 by Penny and Keith Block, MD. The Center's research-based treatment integrates an innovative approach to the best of conventional medicine with scientifically sound complementary therapies -- therapeutic nutrition, botanical and phytonutrient supplementation, prescriptive exercise, and systematic mind-body strategies, to enhance the recovery process. Block has pioneered this "middle ground" approach to cancer care and optimal health. The Block Center is currently the only private North American medical center using chronomodulated chemotherapy. Dr. Block is a member of the National Cancer Institute's PDQ Cancer Complementary and Alternative Medicine (CAM) Editorial Board in Bethesda, MD, and Director of Integrative Medical Education at the College of Medicine at the University of Illinois, Chicago. The Block Center is a full treatment clinic, is a member of the MD Anderson Cancer Center Community Clinical Oncology Program (CCOP), and is also engaged in clinical cancer research with the University of Illinois and other university facilities in the United States and Israel.