Consumption of Dairy Products Increases Ovarian Cancer Risk
A meta-analysis of 21 studies that examined a relationship between dairy product consumption and ovarian cancer risk found that every 10 grams of lactose consumed (the amount in one glass of milk) on a daily basis increased ovarian cancer risk by 13 percent. The study found a stronger link in cohort studies than in case-control studies. (Cohort studies follow a group of people over time and are considered more reliable than case-control studies, which compare patients and healthy control subjects at a single point in time.) Skim, low-fat, and whole milk, yogurt, cheese, and total lactose (dairy sugar) consumption was analyzed in these studies. Previous studies have suggested that galactose, a byproduct of lactose digestion, may have a toxic effect on a woman’s ovaries.
Larsson SC, Orsini N, Wolk A. Milk, milk products, and lactose intake and ovarian cancer risk: a meta-analysis of epidemiological studies. Int J Cancer. Available at http://www3.interscience.wiley.com/cgi-bin/abstract/110575092/ABSTRACT. Accessed September 23, 2005.
Hormone Replacement Therapy Is Only a Temporary Fix
Hormone “replacement” increases cancer risk, but is sometimes prescribed to treat hot flashes. However, these symptoms are likely to return as soon as the treatment is stopped, according to a new report from the Women’s Health Initiative. In May 2002, investigators stopped prescribing the hormones when serious risks of breast cancer, cardiovascular disease, stroke, and dementia were found. The 8,405 women who discontinued estrogens and progesterone were then surveyed. More than half of the women who had had hot flashes prior to beginning hormone therapy suffered recurrences when the treatment was ended. Women who had not had hot flashes prior to starting the hormones tended to remain symptom-free after discontinuing them. The study suggests that hormones are not a long-term solution to hot flashes and supports the use of non-hormonal strategies for dealing with menopausal symptoms.
Ockene JK, Barad DH, Cochrane BB, et al. Symptom experience after discontinuing use of estrogen plus progestin. JAMA. 2005;294:183-93.
Vegan Diet and Lifestyle Changes Slow Prostate Cancer
A new study by Dr. Dean Ornish shows the power of diet and lifestyle changes to improve cancer survival. In a group of men with prostate cancer, prostate-specific antigen (PSA) levels—a marker that tracks prostate cancer growth—decreased by 4 percent after one year on a low-fat vegan diet, complemented by moderate aerobic exercise and stress management. (The diet was supplemented with soy, omega-3 fatty acids, vitamin E, selenium, and vitamin C.) It is unusual for PSA levels to decrease without treatment. A control group saw its PSA levels rise by 6 percent. In addition, six of the men in the control group needed treatment during the one-year study period because their prostate cancer was progressing, but no one in the experimental group needed treatment. Previous studies have shown that the consumption of dietary fat and dairy products increases prostate cancer risk while compounds in tomatoes, soy, and cruciferous vegetables protect against the disease.
Ornish D, Weidner G, Fair WR, et al. Intensive lifestyle changes may affect the progression of prostate cancer. J Urol. 2005;174:1065-70.