Acid-Base Balance, Metabolism and Minerals

Study Overview
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Brief Summary
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Metabolism is controlled by macro- and micronutrients. Protein-rich diets should lead to latent acidosis at tissue level with further negative implications. Food supplements with alkaline salts are available and popular pretending to prevent these changes. Within a randomized double-blind placebo-controlled trial, the investigators tested the hypotheses 1) that a 4-week protein-rich diet induces a latent tissue acidosis and 2) an alkaline supplement can compensate this. Acid-base balance and important metabolic parameters were determined before and after 4 weeks of supplementation by peripheral blood samples, indirect calorimetry and muscle microdialysis before and after a protein-rich test meal.

Official Title
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Randomized, Double-blind, Placebo-controlled Intervention Study on Effects of Basica® on Acid-base Balance, Metabolism and Quality of Life in Elderly Healthy Volunteers.

Conditions
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Acid-Base Balance Disorder, Metabolic Acidosis

Intervention / Treatment
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* Dietary Supplement: alkaline salt mixture
* Dietary Supplement: placebo


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: slightly reduced kidney function (GFR 60-89 ml/min) Body mass index 20.0 - 29.9 kg/m2 normal daily diet composition: 45-50, 35-40, and 15 E% from carbs, fats and proteins, respectively Exclusion Criteria: sorbitol-/fructose-intolerance intake of antacidic drugs vegetarians, vegans intake of any nutritional supplements any cardiovascular, pulmonary, endocrine or metabolic diseases any drug abuse intake of any anticoagulant drugs

Ages Eligible for Study
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Minimum Age: 60 Years
Maximum Age: 70 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Quadruple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: Basica<br>4-week dietary supplementation with an alkaline salt (Basica) | Dietary Supplement: alkaline salt mixture<br>* blood and tissue alkalinisation<br>* Other names: Basica;|
| Placebo Comparator: Placebo<br>4-week dietary supplementation with a placebo | Dietary Supplement: placebo<br>* no blood and tissue alkalinisation<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in muscle dialysate lactate-pyruvate ratio | surrogate measure for muscle tissue pH | before and after 4-weeks of supplementation at baseline (after a 12 hours overnight fast) and 60, 120, and 180 minutes after a protein-enriched test meal | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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acid-base balance, energy metabolism, protein-rich diet, alkaline supplementation, calorimetry, microdialysis, randomized placebo-controlled trial