Dietary calcium, the 16-hydroxyl metabolic pathway of steroids, and sex hormones in blood and urine

摘要

In a recent article in the Journal, Napoli et al (1) reported cross-sectional data in healthy postmenopausal white women, which suggested that a higher calcium intake from dietary sources may be associated with a shift in estrogen metabolism toward the active 16-hydroxyl metabolic pathway and with greater bone mineral density. This study addresses the important field of steroid hormone metabolomics and underscores that steroid metabolite profiling in 24-h urine specimens allows one to uncover physiologically relevant shifts in hormone metabolism, which is usually not possible with the same physiologic plausibility if only single blood measurements are performed. Accordingly, the serum estradiol measurements made by Napoli et al showed no differences between the 3 diet groups under study.