Women who exercise more and keep their weight under control may dramatically reduce their odds of developing breast cancer, a population-based study by a team of investigators at Meharry Medical College and the Vanderbilt-Ingram Cancer Center suggests. The researchers, along with colleagues at the Shanghai Cancer Institute in China, report a strong link between “energy balance” and breast cancer risk in the June issue of Cancer Epidemiology, Biomarkers & Prevention, a journal of the American Association for Cancer Research (AACR).Energy balance represents the difference between energy intake (eating) and energy expenditure (activity).
Breast cancer will be diagnosed in more than 211,000 American women this year, and will claim almost 41,000 lives, making it the second leading cancer killer among women in the United States. While certain factors are known to increase breast cancer risk — including family history and age of first menstruation and onset of menopause — there is a need for more information about those risk factors that can be modified.
Women with low levels of physical activity and higher body mass index levels (weight divided by height) were at more than twice the risk of developing breast cancer than women who undertook approximately three metabolic equivalent hours (MET) per day, per year, of exercise, and had lower BMI levels, the researchers found. This level of exercise is equivalent to about 45 minutes of brisk walking or 20 minutes of vigorous exercise per day.
