December 13, 2006 One year of calorie restriction or exercise yielded similar weight loss, but only weight loss from calorie restriction produced significant decreases in bone-mineral density (BMD) in older adults, according to the results of a randomized study reported in the December 11/25 issue of the Archives of Internal Medicine. write Dennis T. Villarreal, MD, of the Washington University School of Medicine in St. Louis, Missouri, and colleagues. The purpose of the present study was to conduct a 12-month, randomized controlled trial to test the hypothesis that weight loss induced by EX results in less bone loss compared with weight loss induced by CR at clinically important sites of osteoporosis fracture (i.e., hip and spine) in no obese middle-aged men and women. The data reported in this article were obtained as part of an investigation of the feasibility of calorie restriction in healthy volunteers (Comprehensive Assessment of Long-Term Effects of Reducing Intake of Energy [CALERIE]). 3 years. The main endpoint was change in hip and spine BMD, and secondary endpoints were bone markers and hormones. the authors write. These data suggest that EX should be an important component of a weight-loss program to offset adverse effects of CR on bone. Study limitations include the use of hormone therapy by approximately one third of female subjects; the use of dual-energy x-ray absorptiometry, providing information on bone quantity but not bone quality; the relatively small sample size; insufficient power to examine sex differences in BMD responses; and most participants being overweight, limiting generalizability. Our results suggest that regular EX should be included as part of a comprehensive weight-loss program to offset the adverse effects of CR on bone. The National Institutes of Health supported this study. The authors have disclosed no relevant financial relationships. Read the complete news article here: http://www.medscape.com