Effect of Dietary Protein Source on Calcium Metabolism

Calcium Metabolism Clinical Trial

Official title:

Effect of Dietary Protein Source on Calcium Metabolism

Clinical Trial Details — Status: Completed

Administrative data

• NCT number: NCT00187538
• Other study ID #: H9291-19207-05
• Status: Completed
• Phase: N/A
• First received: September 13, 2005
• Last updated: August 20, 2014
• Start date: February 2002
• Est. completion date: July 2013

Study information

• Verified date: August 2014
• Source: University of California, San Francisco
• Contact: n/a
• Is FDA regulated: No
• Health authority: United States: Federal Government
• Study type: Interventional

Clinical Trial Summary

Osteoporosis is a major health concern worldwide. While there are drugs available for the treatment and prevention of osteoporosis, they are not practical for population-wide prevention efforts. Demonstrating the effectiveness of safe and widely available dietary interventions to prevent osteoporosis could have important public health ramifications. Different food sources of dietary protein may have different effects on bone metabolism. Animal foods provide a dietary acid load that may lead to negative calcium balance and increased bone resorption. In contrast, vegetable sources of protein, while providing some acid due to their protein content, provide proportionally more base that counters the dietary acid load. The effect of dairy products, which are rich in animal protein but also contain potential base precursors not found in vegetable foods, has not been established. Finally, soy protein sources may have a dual benefit: soy foods provide base precursors as well as plant estrogens that may have a beneficial effect on bone. We are resubmitting this proposal to randomize postmenopausal women to one of four diets equal in calories, protein, calcium, and sodium. The diets will differ by having 80 percent of the protein from one of four sources: non-dairy animal, vegetable, dairy, or soy foods, resulting in significant differences among the diets in acid, base, and isoflavone content. All food will be prepared and provided by the General Clinical Research Center. The subjects will consume the diets for 6 weeks with measurements of acid-base status, isoflavone excretion, and calcium metabolism. This will be the first intervention study to examine the effect of different sources of dietary protein in whole foods on calcium metabolism. Eventually our findings could have substantial public health implications and provide a widely available and low risk means to help prevent osteoporosis.

Description:

Demonstrating the effectiveness of safe and widely available dietary interventions to prevent osteoporosis could have important public health ramifications. Different food sources of dietary protein may have different effects on bone metabolism. Animal foods provide a dietary acid load that may lead to negative calcium balance and increased bone resorption. In contrast, vegetable sources of protein, while providing some acid due to their protein content, provide proportionally more base that counters the dietary acid load. The effect of dairy products, which are rich in animal protein but also contain potential base precursors not found in vegetable foods, has not been established. Finally, soy protein sources may have a dual benefit: soy foods provide base precursors as well as plant estrogens that may have a beneficial effect on bone. We are resubmitting this proposal to randomize postmenopausal women to one of four diets equal in calories, protein, calcium, and sodium. The diets will differ by having 80 percent of the protein from one of four sources: non-dairy animal, vegetable, dairy, or soy foods, resulting in significant differences among the diets in acid, base, and isoflavone content. All food will be prepared and provided by the General Clinical Research Center. The subjects will consume the diets for 6 weeks with measurements of acid-base status, isoflavone excretion, and calcium metabolism. This will be the first intervention study to examine the effect of different sources of dietary protein in whole foods on calcium metabolism. Eventually our findings could have substantial public health implications and provide a widely available and low risk means to help prevent osteoporosis.

Recruitment information / eligibility

• Status: Completed
• Enrollment: 183
• Est. completion date: July 2013
• Est. primary completion date: December 2012
• Accepts healthy volunteers: Accepts Healthy Volunteers
• Gender: Female
• Age group: 55 Years and older

Eligibility

Inclusion Criteria:

Healthy postmenopausal women

Exclusion Criteria:

No meds affecting bone Normal renal, GI, hepatic function

Study Design

Allocation: Randomized, Endpoint Classification: Efficacy Study, Intervention Model: Single Group Assignment, Masking: Open Label, Primary Purpose: Prevention

Related Conditions & MeSH terms

• Calcium Metabolism

Intervention

Behavioral:
• Dietary
dietary

Locations

Country	Name	City	State
United States	Johns Hopkins University	Baltimore	Maryland

Sponsors (2)

Lead Sponsor	Collaborator
University of California, San Francisco	National Institute of Arthritis and Musculoskeletal and Skin Diseases (NIAMS)

Country where clinical trial is conducted

United States, 

Outcome

Type	Measure	Description	Time frame	Safety issue
Primary	calcium metabolism		after 8 weeks of diet	No