Researchers in St. Louis divided a group of 27 obese men and women . All were physically frail at the start of the study, but one group cut calories, and the other maintained their normal lifestyle. The weight-loss group lost bone mass in the hip area by 2-3 percent, while the other group held steady.
Older, obese adults may be prone to lose bone mass even if they exercise regularly. It's known that weight loss can be accompanied by a decline in bone density, but experts had hoped it could be prevented with exercise.