Women going through menopause gain on average of one pound of body weight each year. New research reveals, however, that efforts to minimize or reverse this trend have the undesirable side effect of decreasing bone mineral density (BMD), putting those who are most successful at controlling weight gain at greater risk of osteoporosis.
?Weight reduction is often encouraged in overweight perimenopausal women and weight maintenance is recommended in normal weight perimenopausal women,? said Dr. Jane A. Cauley of the University of Pittsburgh?s Graduate School of Public Health and co-author of the study. ?However, our research reveals that lifestyle interventions to control weight gain can have negative consequences for a woman?s bone mineral density.?
The results were discovered during the Women?s Healthy Lifestyle Project, a 5-year study of 535 premenopausal women in Allegheny County, Pennsylvania. The project goal was to determine if lifestyle interventions could control cholesterol and weight gain during menopause. The lifestyle interventions focused on a low-fat diet and exercise.
The interventions were successful in preventing weight gain and its associated increases in LDL cholesterol; women in the intervention group gained an average of 2.8 kilograms (6.2 pounds) less than women in the control group. However, during the intervention, women in the intervention group also experienced greater loss in BMD, especially at the total hip and femoral neck.
It was also noted in this study that women taking hormone replacement therapy had slightly less, but still statistically significant BMD loss. ?This study suggests that the use of hormones many not totally protect women from weight loss associated bone loss,? said Cauley. Clinicians need to consider the potential loss of BMD when providing lifestyle and weight loss recommendations to midlife women, according to Cauley.
It is estimated that each year women normally lose 1.15 percent of spine bone BMD and 0.85 percent of femur neck BMD in the immediate postmenopausal period, tapering off to 0.20 percent and 0.57 percent, respectively.
A rapid release version of this paper has been published on-line and will appear in the October 2007 issue of the Journal of Clinical Endocrinology & Metabolism, a publication of The Endocrine Society.
Effects of Weight Control During the Menopausal Transition on Bone Mineral Density
Hyun A. Park, Jung S. Lee, Lewis H. Kuller, and Jane A. Cauley