Losing Weight Through Diet, Exercise May Cut Postmenopausal Women's Risk of Breast Cancer
The combination of menopause and aging causes many changes to a woman’s body. One of those is the potential for weight gain. As we age, our metabolism slows down and we also lose muscle mass, which makes it more difficult for our bodies to burn calories. Menopause just accelerates the loss of muscle mass. That combination makes it really easy to pack on the pounds.
But if those pounds have crept onto your frame, there’s a good reason to focus on working to shed them. MedlinePlus reported on a new study that found that postmenopausal women who lose weight through a healthy diet and exercise may lower the levels of certain hormones in their blood that, in turn, may help them avoid developing breast cancer.
These findings, which were published in the May 21 issue of the Journal of Clinical Oncology, were the first randomized, controlled clinical trial that tested the effects of weight loss on sex hormones in overweight and obese postmenopausal women.
The study followed 439 women who were between the ages of 50 and 75 (with an average age of 58) and who were either overweight or obese, as well as sedentary. These participants were randomly put into four groups that respectively were assigned to exercise (mainly through walking), diet, both diet and exercise, and do nothing. The two groups that were assigned to diet were placed on a plan that not only reduced calories, but also reduced fat and increased the women’s consumption of vegetables, fruits and fiber.
The researchers found that women in the groups that dieted or died and exercised lost an average of 10 percent of their starting weight. These groups of women also lowered their levels of several hormones, including three forms of estrogen and two types of estrogen. One of the most important changes they experienced was an increase in sex hormone binding globulin (SHBG); this is important since high levels of this hormone are associated with reduced breast cancer risk.
Another of the study’s findings also gives women who face losing a lot of weight a reason to get started. That’s because losing as little as five percent of total body weight had a beneficial impact on a woman’s hormone levels. Furthermore, the positive effect actually increased as the woman lost more weight. “The amount of weight lost was key to changes in hormone levels,” researcher Dr. Anne McTiernan, the director of the Prevention Center at the Fred Hutchinson Cancer Research Center, said in a press release on the center’s website. “The biggest effect was through diet plus exercise; exercise by itself didn’t produce much of a change in weight or estrogen.” Dr. Tiernan warned that these findings apply only to overweight or obese women who are not taking hormone-replacement therapy.
This study also was the first to find that losing weight through a healthy diet that emphasized vegetables, fruits and fiber could significantly lower blood estrogen levels in postmenopausal women. “This shows that it’s never too late to make lifestyle changes to reduce your risk for breast cancer,” Dr. McTiernan said.
Dr. McTiernan also believes the study’s findings could be relevant to overweight women who are taking breast cancer prevention drugs. “None of these medications are recommended for use beyond about five years and they can have significant side effects in some women,” she explained. “Weight loss represents an additional option for long-term breast cancer risk reduction without significant or bothersome side effects.”
Primary Sources for This Sharepost:
Fred Hutchinson Cancer Research Center. (2012). Study finds that moderate weight loss reduces levels of sex hormones linked with increased risk of breast cancer.
MedlinePlus. (2012). Dieting may lower hormone levels tied to breast cancer. The National Institutes of Health’s U.S. National Library of Medicine.