Associations of Body Composition Measures and Endogenous Sex-Steroid Hormones among Postmenopausal Women

Several studies have shown a positive association between body mass index (BMI) and endogenous levels of female sex-steroid hormones, but relationship with the body fat mass and the fat free mass components of BMI has rarely been investigated. In this cross-sectional study, we included 265 women from the Danish “Diet, Cancer and Health” cohort who were postmenopausal and never users of hormone replacement therapy and who previously were included in a nested case-control study on breast cancer. Multiple log-linear regression analyses of the association between anthropometric measurements and serum levels of estrone, estrone sulfate and sex hormone binding globulin (SHBG) were performed. We found positive associations between all the anthropometric measurements included and estrone and estrone sulfate, whereas negative associations were found for SHBG. We confirmed previous findings of associations between BMI and serum levels of estrogen and SHBG among postmenopausal women. Associations were in the same direction for the two components of BMI, body fat mass index (BFMI) and fat free mass index (FFMI), and use of these more detailed measures did not give a better prediction of the hormone levels than use of BMI alone.