Body fat does have an effect on your breast cancer risks, but the risks vary based on pre- and post-menopause factors, as well where you carry the most body fat. If you are concerned about your risk for breast cancer, consult with your doctor to determine appropriate changes you can make to reduce your risk.
Premenopausal Risk
Before menopause, women with a higher percentage of body fat and who weigh more than 175 lbs. have a lower risk of breast cancer than women weighing less than 130 lbs., according to Cornell University. Cornell University reported on a study correlating breast cancer and the weight of women at ages 5, 10 and 20. The study found women who were heaviest at age 10 had a lower risk of pre- and post-menopausal breast cancer in comparison to thinner girls. There are several other diseases and health concerns associated with being overweight, so even if your risk is lower, it's important to maintain a body mass index less than 25 throughout your adult life, according to the National Cancer Institute. Even though being overweight lowers your risk of developing breast cancer before menopause, your risk of death from breast cancer increases.
Postmenopausal Risk
The tables turn after menopause, and women who are obese have a 1.5 times higher risk of breast cancer in comparison to healthy women with a stable weight, according to the National Cancer Institute. Changes in your body weight after early adulthood is a risk factor for postmenopausal breast cancer. The body's production and use of estrogen after menopause plays a key role in this increased risk for overweight and obese women. Before menopause, the ovaries primarily produce estrogen, but fat tissue becomes the primary source of estrogen production after menopause. Breast tumors are estrogen-responsive, so increased estrogen in fat tissue makes estrogen levels 50 to 100 percent higher among heavy women in comparison to lean women, according to the National Cancer Institute.
Body Fat Location
Body fat is carried differently among women, and your shape can affect your risk of breast cancer. If you carry body fat in your stomach, you have a higher chance of developing breast cancer than a woman who carries fat on her hips, according to Cornell University.
Considerations
Although body fat does correlate with breast cancer risks, the size of your breast does not increase or decrease your risk of breast cancer. According to the National Cancer Institute, exercise reduces the overall risk of both pre- and post-menopausal breast cancer. Reduce the amount of fat you consume in your diet and perform a minimum of 150 minutes of moderate intensity aerobic exercise weekly, especially if you have an apple-shaped figure.
References
- Cornell University: Breast Cancer and Environmental Risk Factors
- National Cancer Institute: Obesity and Cancer
- "The Breast Cancer Prevention Cookbook"; Vincent Connelly and Hope Ricciotti; 2002
