Comparative Bioavailability of Two Forms of Vitamin C

Study Overview
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Brief Summary
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The purpose of this study is to compare levels of vitamin C in the blood over the 24 hour period following a single 1000 mg dose of vitamin C from ascorbic acid, calcium ascorbate and placebo.

Official Title
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A Randomized, Double-blind, Placebo-controlled Crossover Study Comparing the Bioavailability of Two Forms of Vitamin C in Plasma and Leukocytes Over 24 Hours.

Conditions
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Bioavailability

Intervention / Treatment
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* Dietary Supplement: calcium ascorbate
* Dietary Supplement: ascorbic acid
* Other: placebo


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Healthy as determined by laboratory results and medical history Females not of child bearing potential BMI 18-30 kg/m2 Agrees to consume a low vitamin C diet Non-smoker or ex-smoker >1 year Exclusion Criteria: Pregnant, breastfeeding, or planning to become pregnant during the trial Alcohol >2 drinks per day; alcohol or drug abuse within the past year Cardiac conditions Duodenal ulcer or gastric ulcer, gastritis, hiatus hernia, or gastroesophageal reflux disease (GERD) within past 3 months History irritable bowel syndrome, malabsorption or significant GI disease History of kidney stones Use of medications known to interact with vitamin C Use of supplements containing vitamin C Use of anticoagulants (warfarin), barbiturates, tetracycline antibiotics, beta-blockers, cyclosporine, prednisone, tricyclic antidepressants, diuretics and nitrate medications History of or current diagnosis of cancer Uncontrolled hypertension History of diabetes, renal disease and/or liver disease Unstable psychiatric disorder History of or current immunocompromise History of hemochromatosis or hemoglobinopathies Participation in a clinical research trial <30 days Use of acute medication w/in 72 hours of intervention Unstable medications <90 days Abnormal liver function Serum creatinine > 1.5 x upper limit of normal (ULN) Anemia of any etiology Blood donation w/in the last 2 months Allergy or sensitivity to test articles, foods or beverages provided during the study Cognitive impairment and/or unable to give informed consent

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 60 Years

Sexes Eligible for Study
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All

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Basic Science
Allocation: Randomized
Intervention Model: Crossover Assignment
Masking: Triple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: calcium ascorbate<br> | Dietary Supplement: calcium ascorbate<br> <br> * Other names: vitamin C;|
| Active Comparator: ascorbic acid<br> | Dietary Supplement: ascorbic acid<br> <br> * Other names: vitamin C;|
| Placebo Comparator: placebo<br> | Other: placebo<br> <br> |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Plasma and leukocyte vitamin C concentration |  | 0, 2, 4, 8 and 24 hours | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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vitamin C, calcium ascorbate, ascorbic acid, bioavailability