The Body's Affect on Vitamin C

Launched by NATIONAL INSTITUTE OF DIABETES AND DIGESTIVE AND KIDNEY DISEASES (NIDDK) · Nov 3, 1999

Keywords

ClinConnect Summary

Vitamin C (ascorbic acid, ascorbate) is an essential water soluble vitamin. Our studies at NIH were the first to demonstrate in healthy men and women how changes in a vitamin concentration in human plasma vary as a direct function of the amount ingested, over a wide range. ln the present study, we plan to achieve a prescorbutic vitamin C plasma concentration of approximately 5-10 micromolar in healthy human volunteers. We will gradually replete these subjects with incremental doses of vitamin C to measure how their plasma, red blood cell, and leukocyte concentrations will change as a functi...

Gender

ALL

Eligibility criteria

• * INCLUSION CRITERIA:
• • 10 Males - ages 18 - 35 yrs
• • 10 Females - ages 18 - 35 yrs
• No more than 4 subjects during any period will remain as inpatients on the endocrine/metabolic ward. These subjects will be normal volunteers selected from colleges/universities who will:
• • 1. Spend within a fall or spring semester (approximately 20-26 weeks) as an inpatient resident on the endocrine-metabolic ward at NIH.
• • 2. Be willing to adhere to an ascorbate restricted diet for the duration of the time spent in the study as an inpatient at NlH.
• • 3. Have veins adequate for venipunctures and be willing to undergo venipunctures approximately two to three times per week.
• • 4. Refrain from ingestion of any medication and cigarette smoking and ethanol.
• • 5. Be able to give informed consent.
• EXCLUSION CRITERIA:
• • 1. Subject non-compliance with restricted diet.
• • 2. Pregnancy as determined by history, physical exam and urine b-HCG.
• • 3. History of diabetes mellitus, bleeding disorders, kidney stones, glucose-6- phosphate dehydrogenase deficiency, family history of hemochromatosis/iron overload.
• • 4. Platelet count \<150,000/ul blood; prothrombin time/partial thromboplastin time (PT/PTT) \> 1 second above normal upper limit.
• • 5. Positive test for exposure to human immunodeficiency virus.
• • 6. Positive tests for hepatitis B surface antigen, core antibody or surface antibody.

Trial Officials