Breast cancer is the number two cancer death among women of almost all ethnicities. However, together with regular screenings, a healthy lifestyle can reduce women's risk of getting breast cancer. One major way to lower risk is through weight management. Fat accumulation, particularly around the stomach and breasts, has been shown to significantly increase a women's breast cancer risk.
Visceral Fat
Most Americans are mainly concerned about subcutaneous fat, fat that is located between the skin and the abdominal wall and can be seen by the naked eye or grabbed with their hands. However, the most dangerous type of fat actually lies deeper inside of people. Visceral fat, contained far within the abdomen and surrounding abdominal organs, is associated with many health conditions. Gaining visceral fat has been linked to cardiovascular disease, diabetes, cancer and other health problems.
Distribution
In the body, fat distribution---whether fat is located in the upper or the lower portion of the body--can seriously affect a person's health. Fat stores in the upper portion of the body are much more dangerous than fat below the waistline. This is because upper body fat, particularly around the stomach, is an active, hormone-producing substance. According to the Mayo Clinic, upper body fat is associated with heart disease diabetes, metabolic syndrome, high blood pressure and two types of cancer---one of which is breast cancer. Other medical organizations agree. A 1999 study by New York University School of Medicine found that upper-body fat accumulation can predict breast cancer risk in premenopausal women, particularly in women who are extremely overweight.
Insulin Resistance
A 1996 study by Basil A. Stoll, M.D., of St. Thomas Hospital in London suggests that the connection between fat and breast cancer may be linked to increased insulin resistance. Insulin-resistant women tend to have large deposits of abdominal fat, which can cause the body to create more bio-available estrogen. Stoll found that women with a great deal of fat predominantly in the abdomen had an increased breast cancer risk from puberty onward and believes that the estrogen and insulin may combine to promote the development of cancer in the breast. A study at Yamagata University in Japan had similar findings.
Menopause
The time at which a woman becomes obese can also affect her risk of breast cancer. Body fat gained after menopause has repeatedly been shown to increase the odds of a woman getting breast cancer. However, according to Elizabeth Sonnenschein of New York University, no studies have shown a definitive link between pre-menopausal weight gain and breast cancer. In fact, Sonnenschein's research shows a minute correlation between lower-body fat among pre-menopausal women and lowered cancer risk.
Prevention
Eating a low-fat diet and exercising regularly can prevent weight gain in women. For women who are already obese and wish to lower their breast cancer risk, the American Dietetic Association recommends losing weight through portion control, calorie reduction and 45- to 60-minute sessions of cardiovascular exercise combined with strength training. Women can also speed up weight loss by replacing two low-nutrient snacks with a serving of fruit or vegetables and avoiding processed sugars, particularly in beverages.
Beyond its effectiveness as a weight-control tool, exercise has an additional benefit for women. Because it reduces estrogen accumulations around breast tissue, vigorous exercise has been shown to lower breast cancer risk.
References
- "International Journal of Obesity"; Obesity and Breast Cancer; B.A. Stoll, M.D.; 1996
- "International Journal of Epidemiology"; Body Fat Distribution and Obesity in Pre- and Postmenopausal Breast Cancer; E. Sonnenschein; December 1999
