The News You NeedBy Joseph Gonzales, R.D., and Susan Levin, M.S., R.D.
Vegetarian Diets Help Expel Cancer-Causing Hormones
Vegetarian diets may reduce levels of hormones that contribute to cancer, according to a new study. The study observed how dietary patterns affect breast cancer risk by measuring hormone markers in post-menopausal women. Researchers studied diet records and conducted blood, urine, and fecal tests among women in the study’s three participant groups—a vegetarian group, an omnivorous group, and an omnivorous group with breast cancer.
Results showed that the vegetarian group significantly decreased estrogen production while boosting the hormone sex-hormone-binding-globulin (SHBG), which is known for removing excess and unneeded hormones. The omnivorous participants with breast cancer had the highest amounts of hormones while reporting a poor fiber-to-fat ratio in their diets. The omnivores without cancer did better, but not as well as the vegetarian group.
The author of the study, Mylène Aubertin-Leheudre, Ph.D., concluded that having less body fat, eating less fat, and eating more fiber, particularly cereal fiber, work together to lower estrogen levels in the bloodstream, reducing the risk of breast cancer.
Aubertin-Leheudre M, Hämäläinen E, Adlercreutz H. Diets and hormonal levels in postmenopausal women with or without breast cancer. Nutr Cancer. 2011;63:514-524.
Fiber Decreases Colorectal Cancer Risk
Fiber decreases the risk of colorectal cancer, according to a recent study published in BMJ. This study was part of the World Cancer Research Fund’s Continuous Update Report, which in 2011 upgraded fiber’s protective effects from “probable” to “convincing.” Researchers found for every 10 grams of total fiber or cereal fiber intake, colorectal cancer risk fell 10 percent. In addition, those consuming three servings of whole grains per day decreased their risk by about 20 percent. Other benefits associated with higher fiber intake include decreased risk of type 2 diabetes and heart disease, better weight control, and decreased insulin resistance. Fiber is found only in plant-based foods. The more animal products people eat, the less fiber they get.
Aune D, Chan D, Lau R, et al. Dietary fibre, whole grains, and risk of colorectal cancer: systematic review and dose-response meta-analysis of prospective studies. BMJ. 2011;343:d6617.
World Cancer Research Fund / American Institute for Cancer Research. Continuous Update Project Interim Report Summary. Food, Nutrition, Physical Activity, and the Prevention of Colorectal Cancer. 2011.
Eggs Linked to Prostate Cancer
Eating eggs is linked to developing prostate cancer, according to a recent National Institutes of Health-funded study. By consuming 2.5 eggs per week, men increased their risk for advanced prostate cancer by 81 percent, compared with men who averaged less than half an egg per week. Researchers followed 27,607 men who were part of the Health Professionals Follow-Up Study from 1994 to 2008. For men who already had prostate cancer, eating poultry and processed red meat increased the risk for death.
Richman EL, Kenfield SA, Stampfer MJ, Giovannucci EL, Chan JM. Egg, red meat, and poultry intake and risk of lethal prostate cancer in the prostate specific antigen-era: incidence and survival. Cancer Prev Res. 2011;4:1-12.