Obesity and physical inactivity are independently associated with the development of type 2 diabetes in women. Researchers in America studied 6,249 women between the ages of 20 and 79 years for 17 years. The women were free of heart disease, cancer, and diabetes at the outset. A total of 143 women developed type 2 diabetes during follow-up. After adjusting for a number of factors including body weight, women in the middle and upper thirds of cardiorespiratory fitness, as determined by a treadmill exercise test, had significantly lower risks of diabetes compared to the least fit third. In analyses accounting for multiple factors including aerobic fitness, women who were overweight had a 2.3-fold higher likelihood of developing type 2 diabetes and women who were obese had a 3.7-fold higher likelihood of type 2 diabetes, compared to normal-weight women. In an analysis examining the combined effects of cardiorespiratory fitness and body weight on diabetes risk, it was found that while aerobic fitness had a protective effect in overweight / obese individuals, it did not eliminate their increased risk. The findings indicate that with the rapid growth of diabetes and the continuing rise in obesity rates, health professionals should consider the potential benefits of greater fitness and aggressively counsel their sedentary obese patients to become more physically active and improve their fitness as a cornerstone of diabetes prevention and maintaining normal weight.
Diabetes Care,
March 2008