Safety and Effectiveness of Soy Phytoestrogens to Prevent Bone Loss

Not Applicable

Completed

• Conditions: Osteoporosis
• Interventions: Dietary Supplement: Placebo; Dietary Supplement: Soy isoflavones

• Registration Number: NCT00665860
• Lead Sponsor: Baylor College of Medicine

Brief Summary

The purpose of this study is to determine whether soy isoflavone supplementation is safe and effective to prevent bone loss in postmenopausal women.

Detailed Description

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.

Study Timeline

• Study Start: 2001-04
• Primary Completion: 2006-06
• Study Completion: 2006-06
• Study First Submitted: 2008-04-22
• Study First Submitted QC: 2008-04-22
• Study First Posted: 2008-04-24
• Status Verified: 2020-11
• Last Update Submitted: 2020-11-25
• Last Update Posted: 2020-11-27

Recruitment & Eligibility

• Status: COMPLETED
• Sex: Female
• Target Recruitment: 403

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

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: FACTORIAL

Arm && Interventions

Group	Intervention	Description
1	Placebo	Placebo
3	Soy isoflavones	-
2	Soy isoflavones	-

Primary Outcome Measures

Name	Time	Method
Bone mineral density	One year and two years

Secondary Outcome Measures

Name	Time	Method
Blood biochemical bone markers (osteocalcin, bone-specific alkaline phosphatase, cross-linked N-telopeptides of type 1 collagen)	One year and two years

Trial Locations

Locations (3)

Baylor College of Medicine; 🇺🇸 Houston, Texas, United States

University of Georgia; 🇺🇸 Athens, Georgia, United States

University of California; 🇺🇸 Davis, California, United States