Calcium Retention as Influenced by Dietary Components That Induce an Acid Load

Study Overview
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Brief Summary
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The impact of protein sources such as beef as part of Western diet on calcium retention remains controversial. We propose to test the hypothesis that the positive effect of high protein intake (especially from meat protein) can offset the negative effect of protein-induced net acid load on bone metabolism and the retention of body calcium. Healthy postmenopausal women recruited from the community will consume two diets differing in meat protein and acid load for 7 weeks. Calcium retention from diets will be determined using a highly sensitive measurement of whole body retention of a calcium isotope added to the diet.

Official Title
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Calcium Retention in Postmenopausal Women as Influenced by Beef and Other Dietary Components That Induce an Acid Load

Conditions
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Healthy

Intervention / Treatment
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* Other: High Meat - High Potential Renal Acid Load (PRAL) diet
* Other: Low Protein - Low Potential Renal Acid Load (PRAL) diet


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Average body mass index Normal blood work Normal bone density Exclusion Criteria: Chronic disorder Non-traumatic bone fractures

Ages Eligible for Study
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Minimum Age: 40 Years
Maximum Age: 75 Years

Sexes Eligible for Study
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Female

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Prevention
Allocation: Randomized
Intervention Model: Crossover Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: A<br>Dietary Intervention: High meat and high acid load diet followed by low meat and low acid load diet | Other: High Meat - High Potential Renal Acid Load (PRAL) diet<br>* Menu high in meat protein<br>Other: Low Protein - Low Potential Renal Acid Load (PRAL) diet<br>* Menu low in meat protein<br>|
| Experimental: B<br>Dietary Intervention: Low meat and low acid load diet followed by high meat and high acid load diet | Other: High Meat - High Potential Renal Acid Load (PRAL) diet<br>* Menu high in meat protein<br>Other: Low Protein - Low Potential Renal Acid Load (PRAL) diet<br>* Menu low in meat protein<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Calcium Absorption | After 3 weeks equilibration to the diet, the 2-day menu was extrinsically labeled with Calcium-47 radiotracer and retention was monitored for 28 days by whole body scintillation counting. Percent Calcium-47 absorbed was estimated from the y-intercept of the linear portion of a semilogarithmic plot of percent Calcium-47 retained vs time. | 18 weeks | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Meat protein, acid load, calcium retention, postmenopausal women