New research shows that regular exercise, from mild to intense, can reduce breast cancer risk, even after menopause. But significant weight gain may cancel this out.
Have you heard before that a healthy diet and exercise is good for your health? At the risk of repeating—yet again—what you already know, maintaining a healthy weight and exercising makes a difference for women when it comes to their risk of developing breast cancer.
A new study, just published in the journal, Cancer, reports on the latest findings by researchers at the University of North Carolina. Their study examined data from the Long Island Breast Cancer Study Project for 1,504 women who had breast cancer and 1,555 women who didn’t. The women were between the ages of 20 and 98.
Exercise, but how much?
Though it has long been known that exercise can reduce breast cancer risk, the researchers wanted to determine how much exercise, how often, how intense, when, and whether this works for all types of breast cancer.
Any amount is good
What they found was that women who exercised had a lower risk of developing breast cancer (sound familiar?). This was particularly true for the most common breast cancer, the hormone receptor positive breast cancers.
10 to 19 hours per week was most protective
But what they also found was that those who were most active—those who exercised between 10 and 19 hours each week outside of work activity—had the greatest decrease in breast cancer risk: 30 percent.
But protection is lost with substantial weight gain
The caveat, though, was for women who had been active, but who had gained a lot of weight, particularly following menopause. These women had an increased risk for breast cancer. This suggests that women can lose the protection they earned from staying physically active with a significant increase in weight.
The researchers suggested that the benefit from exercise is probably from reducing insulin resistance and inflammation by keeping energy balance and obesity under control.
Their conclusion: “Collectively, these results suggest that women can still reduce their breast cancer risk later in life by maintaining their weight and engaging in moderate amounts of activity.”
Things you can do to reduce your risk
Men’s health across the life course
Theodore D. Cosco, PhD (Cantab) CPsychol