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 .
Design and baseline characteristics of the soy phytoestrogens as replacement estrogen (SPARE) study--a clinical trial of the effects of soy isoflavones in menopausal women.
Following the results of the Women 's Health Initiative , many women now decline estrogen replacement at the time of menopause and seek natural remedies that would treat menopausal symptoms and prevent bone loss and other long-term consequences of estrogen deficiency , but without adverse effects on the breast , uterus , and cardiovascular system . The results of most soy studies in this population have had limitations because of poor design , small sample size , or short duration . This report describes the study rationale , design , and procedures of the Soy Phytoestrogens As Replacement Estrogen ( SPARE ) study , which was design ed to determine the efficacy of soy isoflavones in preventing spinal bone loss and menopausal symptoms in the initial years of menopause . Women ages 45 to 60 without osteoporosis and within 5 years from menopause were r and omized to receive soy isoflavones 200 mg daily or placebo for 2 years . Participants have yearly measurements of spine and hip bone density , urinary phytoestrogens , and serum lipids , thyroid stimulating hormone , and estradiol . Menopausal symptoms , mood changes , depression , and quality of life are assessed annually . The SPARE study recruited 283 women , 66.1 % were Hispanic white . With a large cohort , long duration , and large isoflavone dose , this trial will provide important , relevant , and currently unavailable information on the benefits of purified soy isoflavones in the prevention of bone loss and menopausal symptoms in the first 5 years of menopause . Given the high proportion of Hispanics participating in the study , the results of this trial will also be applicable to this minority 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 .