Conclusions : Isoflavone treatments exert a moderately beneficial effect against  estrogen-deficient bone loss in women .
The effect appears dependent on whether isoflavone treatments are in aglycone form ; we conclude that beneficial effects against bone loss may be enhanced for isoflavone aglycones
Background : Age-related estrogen deficiency leads to accelerated bone resorption .
There is evidence that , through selective estrogen receptor modulation , isoflavones may exert beneficial effects against  estrogen-deficient bone loss .
Isoflavone aglycones show higher bioavailability than their glycosidic counterparts and thus may have greater potency .
Objective : To summarize evidence , we executed a systematic review and meta- analysis examining isoflavone therapies and bone mineral density ( BMD ) loss in peri- and postmenopausal women .
The effect of soy isoflavone on bone mineral density in postmenopausal Taiwanese women with bone loss: a 2-year randomized double-blind placebo-controlled study
Summary The treatment of 300-mg/day isoflavones ( aglycone equivalents ) ( 172.5 mg genistein + 127.5 mg daidzein ) for 2 years failed to prevent lumbar spine and total proximal femur bone mineral density ( BMD ) from declining as compared with the placebo group in a r and omized , double-blind , two-arm design ed study enrolling 431 postmenopausal women 45–65 years old . Introduction This study evaluated the effects of soy isoflavones on bone metabolism in postmenopausal women . Methods Four hundred and thirty-one women , aged 45–65 years , orally consumed 300-mg/day isoflavones ( aglycone equivalents ) or a placebo for 2 years in a parallel group , r and omized , double-blind , two-arm study . Each participant also ingested 600 mg of calcium and 125 IU of vitamin D3 per day . The BMD of the lumbar spine and total proximal femur were measured using dual-energy X-ray absorptiometry at baseline and every half-year thereafter . Serum bone-specific alkaline phosphatase , urinary N-telopeptide of type 1 collagen/creatinine , and other safety assessment s were examined regularly . Results Two hundred out of 217 subjects in the isoflavone group and 199 out of 214 cases in placebo group completed the treatment . Serum concentrations of isoflavone metabolites , genistein and daidzein , of the intervention group were remarkably elevated following intake of isoflavones ( p < 0.001 ) . However , differences in the mean percentage changes of BMD throughout the treatment period were not statistically significant ( lumbar spine , p = 0.42 ; total femur , p = 0.39 ) between the isoflavone and placebo groups , according to the generalized estimating equation ( GEE ) method . A significant time trend of bone loss was observed at both sites as assessed by the GEE method following repeated measurement of BMD ( p < 0.001 ) . Differences in bone marker levels were not significant between the two treatment groups . Conclusion Treatment with 300-mg/day isoflavones ( aglycone equivalents ) failed to prevent a decline in BMD in the lumbar spine or total femur compared with the placebo group
Conclusions : Isoflavone treatments exert a moderately beneficial effect against  estrogen-deficient bone loss in women .
The effect appears dependent on whether isoflavone treatments are in aglycone form ; we conclude that beneficial effects against bone loss may be enhanced for isoflavone aglycones
Background : Age-related estrogen deficiency leads to accelerated bone resorption .
There is evidence that , through selective estrogen receptor modulation , isoflavones may exert beneficial effects against  estrogen-deficient bone loss .
Isoflavone aglycones show higher bioavailability than their glycosidic counterparts and thus may have greater potency .
Objective : To summarize evidence , we executed a systematic review and meta- analysis examining isoflavone therapies and bone mineral density ( BMD ) loss in peri- and postmenopausal women .