By Joseph Gonzales, R.D., and Susan Levin, M.S., R.D.
Soy Decreases Risk of Breast Cancer Recurrence
Women consuming the most soy products have a lower risk of breast cancer recurrence, according to a new study in the Canadian Medical Association Journal. Researchers tracked soy isoflavones consumed by 524 women with breast cancer. Postmenopausal women who ate more than 42.3 milligrams of soy isoflavones daily had a 33 percent decreased risk of recurrence, compared with women who ate less than 15.2 milligrams per day. Sources of soy isoflavones included soymilk, tofu, and edamame. Eight ounces of soymilk contains roughly 20 milligrams of soy isoflavones.
The study resonates with findings from a 2009 Journal of the American Medical Association study, showing that women previously treated for breast cancer have less risk of recurrence or death if they include soy products in their routine.
Kang X, Zhang Q, Wang S, Huang X, Jin S. Effect of soy isoflavones on breast cancer recurrence and death for patients receiving adjuvant endocrine therapy. CMAJ. Published ahead of print October 18, 2010: doi:10.1503/cmaj.091298.
Shu XO, Zheng Y, Cai H, et al. Soy food intake and breast cancer survival. JAMA. 2009;302:2437-2443.
Advances in Pancreatic Cancer Detection and Prevention
It takes an average of 6.8 years for a pancreatic cancer cell to spread to other organs, and an average of 2.7 years from then until the patient’s death, according to a new study published in the journal Nature. Researchers used genetic testing methods to detect cancer progression by identifying specific genes thought to influence cancer growth. These timelines for disease progression may be useful for new screening methods in hopes of detecting cancer earlier.
Meanwhile, an Italian study in Cancer Causes and Control shows that diets rich in fruits and vegetables can reduce pancreatic cancer risk. Research participants who consumed the most fruits and vegetables had an estimated 40 percent reduction in risk, compared with those who ate the least. The study found that frequent meat consumption can double risk and that table sugar and white potatoes also increase risk. The researchers suspect insulin resistance may play a role in pancreatic cancer.
Yachida S, Jones S, Bozic I, et al. Distant metastasis occurs late during the genetic evolution of pancreatic cancer. Nature. 2010;467:1114-1117.
Polesel J, Talamini R, Negri E, et al. Dietary habits and risk of pancreatic cancer: an Italian case-control study. Cancer Causes Control. 2010;21:493-500.
Vegetables Reduce Breast Cancer Risk
Women consuming more vegetables have a decreased risk of breast cancer, according to a recent study published in the American Journal of Epidemiology. Researchers followed the diets of 51,928 participants in the Black Women’s Health Study. Participants who ate two or more servings of vegetables per day had a 43 percent decreased breast cancer risk, compared with those who ate less than four servings per week. Cruciferous vegetables (e.g., broccoli, cauliflower, and kale) and carrots had the largest impact on breast cancer risk.
Boggs DA, Palmer JR, Wise LA, et al. Fruit and Vegetable Intake in Relation to Risk of Breast Cancer in the Black Women’s Health Study. Am J Epidemiol. Published ahead of print October 11, 2010. doi: 10.1093/aje/kwq293.