Soy and Isoflavones Effect on Bone

Osteoporosis Clinical Trial

Official title:

Soy Proteins and Isoflavones Impact Bone Mineral Density in Older Women

Clinical Trial Details — Status: Completed

Administrative data

• NCT number: NCT00668447
• Other study ID #: AG0102
• Secondary ID: USDA CONR-2001-0
• Status: Completed
• Phase: Phase 4
• First received: April 25, 2008
• Last updated: April 25, 2008
• Start date: November 2001
• Est. completion date: June 2005

Study information

• Verified date: April 2008
• Source: National Institute on Aging (NIA)
• Contact: n/a
• Is FDA regulated: No
• Health authority: United States: Federal Government
• Study type: Interventional

Clinical Trial Summary

The purpose of this study is to test the effect of 1 year of added dietary soy protein and/or soy isoflavones on bone mineral density in late postmenopausal women.

Description:

Although soy foods contain several components (isoflavones and amino acids) that could potentially have positive effects on bone health, there are few long term, large, clinical trials using soy as a means of improving bone mineral density. The objective of this study is to provide daily soy protein and isoflavones to healthy older women in order to answer three major questions:

1. Does soy protein alone affect bone metabolism?

2. Do isoflavones, given with soy protein, affect bone metabolism?

3. What dose of isoflavones affects bone in older women?

We hypothesize that soy protein will have a beneficial effect on bone in older women compared to control protein. Further, we hypothesize that there will be an additional benefit to bone in women who receive soy protein plus isoflavones (at both doses) compared to soy protein alone.

Both control and soy proteins used in the study were isolates, meaning they were the highest concentration of protein (85-90% by weight) in order to minimize the volume of protein supplement that each woman was asked to ingest on a daily basis. The soy protein was an alcohol-washed, soy protein isolate containing 90% protein and negligible isoflavone (0.2 mg/g product). The control protein was a mix consisting of 50% protein from sodium caseinate, 25% protein from whey protein and 25% from egg white protein. The use of a mix of proteins as a control provides a more balanced level of amino acids, mimics the real life mix of proteins that humans typically consume, and avoids the unique characteristics of one source of protein. In order to maintain the dietary protein intake constant, the participant was counseled to decrease her intake of other sources of protein from primarily animal sources by approximately 3 ounces per day (the approximate equivalent of the protein powders). The isoflavones tablets each contained 57 mg of total isoflavone from primarily genistein, glycitein, and daidzein and their beta-glycosides.

Recruitment information / eligibility

• Status: Completed
• Enrollment: 97
• Est. completion date: June 2005
• Est. primary completion date: June 2005
• Accepts healthy volunteers: Accepts Healthy Volunteers
• Gender: Female
• Age group: 65 Years and older

Eligibility

Inclusion Criteria:

• Postmenopausal women 65 years old or older

• Able to travel to the clinical sites for follow-up visits

Exclusion Criteria:

• History of disease that may affect bone metabolism (including Paget's disease, primary hyperparathyroidism, osteomalacia, untreated hyperthyroidism, or multiple myeloma)

• Cancer of any kind (except basal or squamous cell of skin) in past 5 years

• Use of any of the following medications within the past 2 years: calcitonin, calcitriol, heparin, phenytoin, phenobarbital

• Use at any time of bisphosphonates, long-term corticosteroids (over 6 months), methotrexate, or fluoride

• Estimated creatinine clearance less than 50 ml/min

• History of chronic liver disease or evidence of liver disease on screening

• History of hip fracture

• Known vertebral fracture within the past year

• Vegans

Study Design

Allocation: Randomized, Endpoint Classification: Efficacy Study, Intervention Model: Factorial Assignment, Masking: Double Blind (Subject, Investigator, Outcomes Assessor), Primary Purpose: Treatment

Related Conditions & MeSH terms

• Osteoporosis

Intervention

Dietary Supplement:
• Soy Isolate
20 grams of powder mixed in beverages or food daily for one year
• Control protein
20 grams of powder mixed in beverages or food daily for one year
• Novasoy isoflavones
3 tablets daily for one year
• Placebo tablets
3 tablets daily for one year

Locations

Country	Name	City	State
United States	University of Connecticut Health Center	Farmington	Connecticut

Sponsors (2)

Lead Sponsor	Collaborator
United States Department of Agriculture (USDA)	University of Connecticut

Country where clinical trial is conducted

United States, 

References & Publications (3)

Alekel DL, Germain AS, Peterson CT, Hanson KB, Stewart JW, Toda T. Isoflavone-rich soy protein isolate attenuates bone loss in the lumbar spine of perimenopausal women. Am J Clin Nutr. 2000 Sep;72(3):844-52. — View Citation

Arjmandi BH, Lucas EA, Khalil DA, Devareddy L, Smith BJ, McDonald J, Arquitt AB, Payton ME, Mason C. One year soy protein supplementation has positive effects on bone formation markers but not bone density in postmenopausal women. Nutr J. 2005 Feb 23;4:8. — View Citation

Evans EM, Racette SB, Van Pelt RE, Peterson LR, Villareal DT. Effects of soy protein isolate and moderate exercise on bone turnover and bone mineral density in postmenopausal women. Menopause. 2007 May-Jun;14(3 Pt 1):481-8. — View Citation

Outcome

Type	Measure	Description	Time frame	Safety issue
Primary	Bone turnover markers		baseline, 3 months, and 1 year	No
Secondary	Bone Mineral Density		Baseline, 6 and 12 months	No
Secondary	Quality of life measured by Medical Outcomes Short Form		Baseline, 6 and 12 months	No
Secondary	Medication Side Effects		3 , 6, 9, and 12 months	Yes
Secondary	Adherence to dietary intervention through the use of 24-hour recall		3, 6, 9, and 12 months	No
Secondary	Long-term medication behavior self-efficacy scale		3, 6, 9, and 12 months	No