Diets low in fat and high in fruits and vegetables apparently have no effect on the return of breast cancer, according to a seven-year government study released earlier this month. The study is of particular importance to the 2.4 million breast cancer survivors, and to states like Texas, where over 12,000 women are expected to be diagnosed with the disease this year and over 25% of the population is going without health insurance.
Published in the Journal of the American Medical Association on July 18th, the study focused on over 3,000 women successfully treated for early-stage breast cancer. Average age of participants was fifty-three, and ten percent died within the course of the study, mostly due to a recurrence of the disease. The cancer returned for approximately the same number of individuals in each group.
Diets assigned to 1,537 of the participants exceeded the Recommended Daily Allowance (RDA) of five fruits and vegetables per day, and consisted of five daily vegetable servings, three fruit servings, sixteen ounces of vegetable juice, and thirty grams of fiber. A “serving” was to equal one-half cup, French fries and iceberg lettuce could not be counted, and only fifteen to twenty percent of calories could be derived from fat. Control groups were given educational literature on the importance of eating at least the RDA of fruits and vegetables.
But the study is already undergoing criticism from healthcare professionals and researchers, many of whom believe the causes of serious diseases like cancer are multi-dimensional, and that studies focusing on a few macronutrients or food groups — with few other controls — may be unable to yield the intended data with accuracy. Previous studies on the link between healthy diet and the prevention of breast cancer have returned mixed results at best.
Susan M. Gapstur, of the Feinberg School of Medicine at Northwestern University, is one of those asking pointed questions. “Should we really have focused on dietary components like fruits, vegetables, and fat? Or should we be focusing, in addition to diet, on lifestyle factors including physical activity and weight?”
The call to approach nutritional studies differently from studies on pharmaceutical medicines is growing stronger. Steve Mister, President and CEO of the Council for Responsible Nutrition, urged colleagues during this May’s symposium, The Workshop, to consider alternative methods for studying nutrition and the effects of dietary supplements. “nutrients have beneficial effects on multiple body tissues, and interact in a dynamic fashion with other nutrients,” said Jeffrey Blumberg, Ph.D., of the Friedman School of Nutrition Science and Policy at Tufts University, and a Workshop attendee.
In other words, simply linking one nutrient — let alone entire food groups — with a particular outcome, without taking into account this complex interaction, may yield inaccurate or incomplete results. The government study did not control for organic, versus conventionally-grown foods, nutrient levels, source of nutrients (which have been linked with osteoporosis in studies focusing on calcium), or lifestyle factors (including physical activity, weight, calorie consumption, other food consumption, and stress). Nor did it control for environmental factors, or other variables associated with breast cancer, including obesity and exposure to certain chemicals linked with breast cancer.
Texas has a particular interest in the accuracy and proper portrayal of such studies, as breast cancer is the second most commonly diagnosed cancer in Texas women. An Ecological Study of the Association of Environmental Chemicals on Breast Cancer Incidence in Texas by Y.M. Coyle and colleagues, found that twelve toxicants released into the environment by industry were positively associated with breast cancer in that state. Those twelve were Environmental Protection Agency (EPA) Toxic Release Inventory (TRI) “chemicals designated as carcinogens or had estrogenic effects associated with breast cancer risk.” The release of these chemicals, furthermore, was “consistently reported to EPA TRI for multiple counties in Texas during 1988 – 2000,” which included years for which the study used data.
Some of the chemicals associated with breast cancer rates were formaldehyde, methylene chloride, styrene, tetrachloroethylene, trichloroethylene, chromium, cobalt, copper, and nickel. Styrene was the “most important” chemical linked with the disease, affecting men and women of all ages, commonly used for food storage and preparation, and released from building materials, tobacco smoke, and industry.
The government study has been further criticized for not highlighting the many beneficial effects of better eating habits, including fewer incidences of other cancers, and improved overall wellbeing. One fear is that consumers, including breast cancer survivors, will read abstracts of the report and begin to believe that high intake levels of fruits and vegetables are simply unimportant.
If these fears were to come to fruition, and the study was to have a negative effect on the population’s eating habits, the healthcare and health insurance industries of Texas could be devastated with higher incidences of diseases already at epidemic levels in the state, including obesity and diabetes. Even a slight increase in rural, uninsured residents seeking care in the larger cities of Dallas, Houston, and Austin, could add enough weight to functionally collapse those cities’ healthcare systems.
What many don’t know, but should, is that the release of such results must be analyzed within their appropriate context, not sensationalized by high-impact headlines or incomplete reports. Common sense, overall, should take hold. Fruits and vegetables have always been good for the human population — throughout cultures, throughout technological eras. In other words, until we can alter our very DNA, keep eating those salads.
Without a doubt, how nutritiously you eat affects your health. How you take care of yourself will certainly affect you as you age, and eventually your wallet, as well.
Pat Carpenter writes for Precedent Insurance Company. Precedent puts a new spin on health insurance. Learn more at Precedent.com