Study examines effects of dietary weight loss, exercise on insulin resistance among postmenopausal women

NEW YORK — A new study that is slated to appear in the October issue of the American Journal of Preventive Medicine found that postmenopausal women may improve their insulin sensitivity through such interventions as diet, exercise, or a combination of the two.

The subjects, which were inactive, overweight/obese postmenopausal women between the ages of 50 and 70 years, were assigned to one of the following groups during the study: dietary weight-loss program (118 subjects); exercise program (117 subjects); a combined program of exercise and diet (117 subjects); or control (87 subjects). The diet intervention was a group-based reduced-calorie program with a 10% weight-loss goal, while the exercise intervention was 45 min/day, 5 days/week of moderate-to-vigorous intensity aerobic activity, the researchers said.

The research, which was conducted between 2005 and 2009 and analyzed in 2010, found that the diet and diet/exercise combination programs garnered the best results, with insulin resistance decreasing by 24% and 26%, respectively. Groups in the exercise and control groups only saw respective decreases of 9% and 2%. These effects were similar in middle-aged (ages 50 to 60 years) and older women (ages 60 to 75 years).

This study was supported by a grant from the National Cancer Institute at the National Institutes of Health.