Regular resistance training helps to strengthen the muscles that support your breasts but it does more than improve the way your chest looks – it helps keep your breasts healthy too. One of the biggest concerns women face as they age is protecting their breasts against cancer. The average woman has a one in eight chance of developing breast cancer at some point in her life. Breast cancer is the second leading cause of cancer death among women, second only to lung malignancies. The good news? More research shows exercise offers some degree of protection against breast cancer.
Not only does exercise decrease the risk of getting breast cancer – regular physical activity reduces the risk of breast cancer recurrence in women diagnosed with it. That’s why more doctors are telling breast cancer patients to exercise. Even women that are undergoing breast cancer treatment can benefit from moderate amounts of lower intensity exercise.
Exercise and Breast Health: What Studies Show
A number of studies have shown a link between exercise and a reduced risk for breast cancer. In fact, a recent meta-analysis looked at 37 studies published between 1987 and 2013 involving more than 4 million women. This study showed women that exercised an hour or more each day had a 12% lower risk for developing breast cancer. Other research has shown greater rates of risk reduction, up to 30%. On the other hand, hormone replacement therapy appears to negate some of the breast health benefits of exercise.
How Does Exercise Lower Breast Cancer Risk?
Many breast tumors are estrogen-dependent. This means they grow in response to the hormone estrogen. Estrogen is broken down by your body into different metabolites. These metabolites differ in the way they affect breast tissue. Some research shows exercise shifts estrogen breakdown towards estrogen metabolites that are less likely to stimulate breast tissue and trigger growth of breast cancer.
How much exercise does it take to get the breast health benefits of exercise? According to a study involving 391 pre-menopausal women carried out at the University of Minnesota, 30 minutes of moderate to high-intensity exercise most days of the week was enough to favorably affect estrogen metabolism. Women who exercise regularly also tend to have lower total estrogen levels than women who are sedentary. When you have lower total estrogen circulating in your body, breast tissue is less likely to be stimulated or encouraged to grow abnormally to form cancer.
Another way exercise may lower breast cancer risk is related to its effects on insulin. Estrogen isn’t the only hormone that encourages breast cells to divide. In animals, insulin stimulates the growth of cells, including breast cells, and promotes the growth of breast tumors. One study carried out at Albert Einstein University found women with insulin levels in the top third had twice the risk of breast cancer compared to those in the lowest third. Exercise helps to improve insulin sensitivity and lower insulin levels. Women with insulin resistance and type 2 diabetes also appear to have a higher risk of breast cancer.
Exercise helps control body weight. After menopause, women who are overweight or obese have a higher risk for breast cancer relative to lean women. Fat tissue produces hormones called androgens that can be converted to estrogen. After menopause, ovarian production of estrogen shuts down, but you continue to produce some estrogen from fat. Obese and overweight women produce more estrogen after menopause than lean women. This estrogen can promote breast cell growth.
What Type of Exercise is Best for Breast Health?
Some studies show lower intensity exercise like walking for 30 minutes or more a day slightly lowers the risk, but most research suggests vigorous exercise is better than walking. The key is to be consistent. The benefits of exercise for breast cancer prevention appear to be greatest for women who had children, are not overweight and have no family history of breast cancer.
Take a Multi-Pronged Approach to Breast Health
Exercise is one tool in your breast health arsenal but you’ll get more bang for your buck when you combine it with a breast-healthy diet. Some research has linked a diet rich in plant-based foods with a lower risk for breast cancer. A recent study found a link between red meat consumption and a higher breast cancer risk. This study suggested that younger women can lower their risk for breast cancer by 14% just by replacing one serving of red meat a day with poultry, fish or plant-based sources of protein like nuts, beans, and lentils.
Fruits and vegetables are a good source of cell-protective antioxidants and fiber that may also be protective. Mushrooms have special significance when it comes to breast health. Research shows they’re rich a natural compound that prevents the conversion of testosterone (produced by fat tissue) to estrogen. You don’t need to eat “fancy” mushrooms to get the benefits. Simple button mushrooms, the common white ones at the grocery store, offer this benefit.
Cruciferous vegetables like broccoli, cabbage, and kale are a rich source of natural chemicals that help your liver detoxify and convert estrogen to safer forms that are less likely to stimulate breast cells. Here are some other cruciferous vegetables to add to your grocery list:
Arugula
Bok choy
Brussels sprouts
Cabbage
Cauliflower
Collard greens
Radishes
Turnips
Watercress
Wasabi
Enjoy eating more veggies and keep exercising to keep your breasts healthy and lower your risk for breast cancer!
References:
American Cancer Society. “What are the key statistics about breast cancer?”
BreastCancer.org. “Exercise”
Time. “How Exercise May Lower Breast Cancer Risk”
Science Daily. “Elevated Insulin Linked To Increased Breast Cancer Risk”
JCO January 1, 2011 vol. 29 no. 1 7-10.
BreastCancer.org. “Controlling Insulin Levels Key for Diagnosed Women”
Eurekalert.org. “Regular Physical Activity Reduces Breast Cancer Risk Irrespective of Age”
Recent Results Cancer Res. 2011;186:13-42. doi: 10.1007/978-3-642-04231-7_2.
Medical News Today. “Could red meat consumption increase breast cancer risk?”
Am J Clin Nutr December 2013 ajcn.061184.
National Cancer Institute. “Cruciferous Vegetables and Cancer Prevention”
Related Cathe Articles:
Short, Intense Exercise May Reduce Your Risk of Breast Cancer
Exercise and Breast Cancer Prevention: Does It Matter What Age You Begin Working Out?
Are High-Sugar Diets Linked with Breast Cancer?
Metabolic Health May Be More Important Than Body Weight for Breast Cancer Risk
