Phytoöstrogene und Knochenstoffwechsel

Zusammenfassung

Insgesamt lässt sich anhand der vorhandenen Daten feststellen, dass Phytoöstrogene in vielfacher Weise in den Knochenstoffwechsel eingreifen. Klinische Studien zeigen einen geringgradigen positiven Effekt auf Knochenmineralgehalt und Knochendichte an verschiedenen Messpunkten, wobei jedoch die Datenlage als kontrovers zu beurteilen ist. Offensichtlich existieren eine Vielzahl von Einflussfaktoren, die die Effektivität einer Supplementierung von Phytoöstrogenen auf den Knochenstoffwechsel verändern, darunter Körpergewicht, körpereigene Equolproduktion, Dauer der Postmenopause vor Therapiebeginn, Kalziumgehalt der Nahrung oder konkomitante Hormontherapie. Festzustellen ist außerdem, dass bis dato keine klinische Endpunktstudie vorliegt, die eine positive Wirkung von Phytoöstrogenen auf die Knochenfrakturrate nachweist. Zusammenfassend ist daher eine Phytoöstrogensupplementierung zur Prävention von Knochenfrakturen nicht indiziert.

Summary

Phytoestrogens are capable of modulating bone metabolism in various ways. Clinical studies demonstrate an osteoprotective effect ofa phytoestrogen-rich diet as well as phytoestrogen supplementation on bone mineral density and bone strength. Data as to the magnitude of this effect are, however, controversial. A number of factors associated with variations in the osteoprotective efficacy of phytoestrogens have been described, among them equol production, duration of postmenopause before the initiation of phytoestrogen supplementation, dietary calcium, and concomitant hormone therapy. Moreover, there are no intervention trials assessing the effect of phytoestrogens on clinically relevant endpoints such as fracture rates. Therefore, phytoestrogen supplementation cannot be recommended for the prevention of bone fracture.

Schlüsselwörter

Phytoöstrogene - Knochenstoffwechsel - Knochenfrakturen

Keywords

Phytoestrogens - bone metabolism - bone fracture

• Literatur

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