Safety and Effectiveness of Soy Phytoestrogens to Prevent Bone Loss

Over-the-counter soy isoflavone supplement usage is becoming common among postmenopausal women. However, there is no documented scientific evidence of its long-term safety and efficacy in preventing osteoporosis. Our primary goal is to determine the safety, efficacy, and optimal dosage of isoflavone supplementation to reduce bone loss in postmenopausal women. The multi-state, multi-institutional design ensures that the study results are representative of postmenopausal women in the U.S. population. Confirming the skeletal benefits of soy isoflavones could translate into reduced healthcare costs related to osteoporosis.

Inclusion criteria

• Must be able to swallow the pills
• No menses for 12 months
• Blood follicle stimulating hormone great than 30 IU/mL
• Lumbar spine bone mineral density t-score equal to or greater than -1.5

Exclusion criteria

• Strict vegetarians
• Current or recent smokers (within last five years)
• Abnormal screening mammogram, Pap smear and blood chemistries
• Clinical diagnosis of osteoporosis, spine and/or hip fracture, cancer, liver, kidney, gallbladder and heart disease
• Clinical diagnosis of psychiatric disorder
• Any allergic reactions to soy products
• Current treatment with bisphosphonates, calcitonin, fluoride, corticosteroids, tamoxifen, raloxifene, HRT, premarin, farestron and letrozole
• Current usage of black cohosh, blue cohosh, dong quai, Caltrate 600+Soy, Estroven, ginseng, Healthy Women, Natural Estrogen, Opti-Soy, PhytoFem, Probalance, Promensil, Remifemin, Rimostil and Trinovin