New Breast Cancer Prevention Essay Research Paper

New Breast Cancer Prevention Essay, Research Paper

Researchers Link Diet To Prevention

Breast cancer is the most common malignant tumor among women and is the

number two killer of women in the United States. Approximately one woman in nine will develop breast cancer in her lifetime (DeGregorio & Wiebe, 1995). The most common form of cancer found in women, breast cancer is devastating socially, psychologically, and physically in ways that too often are considered secondary to the disease process itself. According to Dr. Paul Kehun (1991), a caner surgeon, breast cancer is one of the most feared diseases for women.

Breast cancer has become a major medical problem for women and while progress has been made, 150,000 new cases of breast cancer are diagnosed each year and 50,000 women are dying of the disease each year. In recent statistics published by the National Cancer Institute, the incidence of cancer of the breast in both black and white women is higher today than for any other year since 1973. This disease, as we see it, has not been conquered; innovative research must continue in order to find a cure.

Of all the environmental factors known to influence cancer, diet appears to be one of the most significant. A wide variety of dietary factors are thought to be important in altering cancer initiation, promotion, and progression, as well as in the prevention of cancer. Breast cancer incidence in women consuming traditional Asian diets is approximately 10% that of general female population of the United States. Asian diets are low in red meat and fats but rich in grains such as rice and high in soybeans products such as tufu and miso. Although such diets contain many components other than soy, factors found in soybeans have been reported to provide important protection against initiation, promotion, or progression of breast cancer in animal models. As Hakkak et al. (2000) demonstrated, experimental studies suggest that dietary bovine milk products may exert inhibitory effects on the growth of several tumor types.

This study was conducted to determine the possible preventive effects of diets containing soy protein isolate or bovine whey proteins on DMBA-induced breast tumors in rats. The experiments were created to determine the effects of long-term consumption of these proteins in diets that were formulated to meet the allowances recommended by the American Institute of Nutrition for the rat.

Recent research indicates that babies whose diet includes specific proteins found in some foods have a reduced lifetime risk of breast cancer, Arkansas Children s Nutrition Center researchers say. If a minor class of chemically modified cow s milk protein called whey is included in the diets of baby rats instead of milk s major protein, casein, their lifetime incidence of breast cancer is cut in half, researchers state. The researchers also at ACH have found that isolates of soy protein reduced breast cancer by 25%, compared with casein.

The study that got these results was conducted at the Arkansas Children s Hospital under the supervision of Doctor Thomas Badger. The study was conducted to determine the protective effects of two common dietary proteins, soy protein isolate (soy), and bovine whey, against chemically induced mammary tumors in female Sprague Dawley rats. Rats were fed AIN-93G diets having casein, soy or whey as the sole protein source. Rats within the same dietary groups were mated to obtain the F1 and F2 generations. All the rats did grow well on all three diets, but casein-fed rats gained slightly more body weight than soy or whey-fed rats. When 50% of the casein-fed rats had at least one mammary tumor, lower tumor incidences (24%-34%) were observed in the soy-fed rats and whey-fed groups. When 100% of the casein-fed rats had at least one tumor, soy-fed rats had a lower tumor incidence (77%) in experiment B, but not in experiment A, and there were no differences in tumor multiplicity. Whey-fed rats had lower mammary tumor incidence and multiplicity than casein-fed rats in both experiments. The results indicate that diets rich in soy reduce the incidence of chemically induced mammary tumors by approximately 20%. Furthermore, whey appears to be at least twice as effective as soy in reducing both tumor multiplicity and incidence.

Hakkak el al. (2000) suggests that cancer rates in countries with high consumption of soybeans are lower than those in the Untied States, where less soy products are consumed, and cancer rates increase in the second generation of families that migrate to the Untied States form these countries as their diet becomes Westernized. Data from this study validate the breast cancer prevention claims for experimental diets containing soy protein isolate as reported by others. Furthermore, these data extend our knowledge on soy protein-containing diets and add new information on another dietary factor of animal origin, whey protein, with respect to chemically induced breast cancer. Results from this study demonstrates clearly that diets containing isolated soy protein or whey protein can significantly increase the age of onset of DMBA-induced tumors and reduce the percentages of rats that develop tumors.

To this date, this is the first demonstration that rats fed whey protein-containing diets develop fewer DMBA-induced breast tumors than rats fed either casein or soy-based di