(HealthDay News) – Postmenopausal weight loss through diet and the combination of diet and exercise is associated with a significant reduction in serum estrogens and free testosterone, according to a study published online May 21 in the Journal of Clinical Oncology.
Kristin L. Campbell, PhD, from the University of British Columbia in Vancouver, Canada, and colleagues conducted a 12-month trial to investigate the individual and combined effect of a reduced-calorie weight-loss diet and exercise on serum sex hormones. Overweight and obese postmenopausal women (mean age, 58 years; mean body mass index, 30.9kg/m²) were randomly allocated to one of four groups: reduced-calorie weight-loss diet (diet; 118 women); moderate- to vigorous-intensity aerobic exercise (exercise; 117 women); combined reduced-calorie weight-loss diet and moderate- to vigorous-intensity aerobic exercise (diet + exercise; 117 women); or control (87 women).
Compared with controls, the researchers noted a significant decrease is estrone in the diet (9.6%), exercise (5.5%), and diet + exercise (11.1%) groups. There was also a significant decrease in estradiol with diet (16.2%) and diet + exercise (20.3%), but the reduction with exercise was not significant (4.9%; P=0.10). Sex hormone-binding globulin increased significantly with diet (22.4%) and with diet + exercise (25.8%). Free estradiol and testosterone decreased significantly with diet (21.4 and 10.0%, respectively) and with diet + exercise (26.0 and 15.6%, respectively). The effect on estrogens and sex hormone-binding globulin was greater with greater weight loss.
“Weight loss significantly lowered serum estrogens and free testosterone, supporting weight loss for risk reduction through lowering exposure to breast cancer biomarkers,” the authors write.
One author disclosed financial ties to the pharmaceutical industry.