Bone Mineral Density & Weight Loss
When it comes to maintaining strong bones as we age, is it better to lose weight by severely reducing your caloric intake or by exercising instead? Researchers recently set out to examine whether one weight loss method was superior to the other in terms of lost bone mineral density (BMD).
The researchers observed 48 adults (mean age 57) who were
randomly assigned for a year to one of three study groups: a calorie-
restricted (CR) group, a regular exercise (EX) group and a healthy lifestyle (HL), or control, group. Each group was measured for
changes in hip and spine BMD.
By the end of the study period, body weight had decreased similarly in both the CR and EX groups, but not in the HR group. However, the CR group also showed a decrease in BMD in the spine, whereas the EX group did not demonstrate any decrease in BMD.
Writing in the Archives of Internal Medicine (2006; 166 , 2502–10), the researchers concluded that “CR-induced weight loss,
but not EX-induced weight loss, is associated with reduction in BMD
at clinically important sites of fracture. These data suggest that EX should be an important component of a weight loss program to offset adverse effects of CR on bone.”
The bottom line? This study underscores the importance of regular physical activity for preventing future bone loss, especially in middle-aged clients.