Phytoestrogens and bone health

The major isoflavones in soy are genistein, daidzein and glycitein (reviewed by Setchell, 1998 Setchell and Cassidy, 1999). Isoflavone content varies among soybean varieties, growing conditions and soil (Wang and Murphy, 

---

Studies have demonstrated that treatment with soy or phytoestrogen enriched diets is effective in conserving bone in rodent models of osteoporosis (Anderson and Gamer, 1998 Ishimi et al, 2000 Draper et al, 1997). The mechanism of action of phytoestrogens on bone health is unclear but several mechanisms including inhibition of bone resorption and stimulation of bone formation maybe involved (Fanti etal, 1998 Ishimi e/a/., 1999 Picherit eta/., 2000). Limited data from studies in postmenopausal women have indicated that phytoestrogen supplements have a small, beneficial effect on bone loss in the lumbar spine (Alekel et al, 2000 Potter et al, 1998 Somekawa et al, 2001). 

VALTUENA S, CASHMAN K D, ROBINS S P, CASSIDY A, KARDINAAL A and BRANCA F (2003) Investigating the role of natural phytoestrogens on bone health in postmenopausal women. Br J Nutr. in press. 

Banes S. What is the safe level of phytoestrogen intake Phytoestrogens in food and bone health. Final Meeting of the European Concerted Action on Phytoestrogens in Food and Bone Health, Versailles, Oct 4—6, 2001. 

Hanna K, Wong J, Patterson C, O Neill S, Lyons-Wall P. Phytoestrogen intake, excretion and markers of bone health in Australian women. Asia Pacific J. Clin. Nutr. 13 (Suppl.), S74, 2004. 

---