Insulin resistance ups breast cancer risk

BRISBANE, Australia, July 8 (UPI) -- Overweight, insulin resistant women are at greater risk of advanced breast cancer diagnosis, University of Melbourne researchers said.

Insulin resistance is most commonly caused by being overweight and inactive and is often a precursor to type 2 diabetes.

University of Melbourne researcher Dr. Anne Cust, a key collaborator on an international study, tracked more than 60,000 Swedish women over a 20-year-period from 1985 to 2005. All were cancer free when recruited.

The researchers found that women who were overweight or had signs of insulin resistance -- such as elevated blood glucose or insulin levels -- were about 50 percent more likely to be diagnosed with an advanced breast cancer tumor.

"Women with insulin resistance or who were overweight were less likely to be diagnosed with stage 1 breast cancers but at greater risk of being diagnosed with stage 2 to 4 tumors -- larger more advanced cancers," Cust said. "We know that being overweight and having insulin resistance is a risk factor for getting cancer but -- in the case of breast cancer -- our study indicates that the cancer will be more advanced."

The findings were presented at the Population Health Conference in Brisbane.