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ClinicalTrials.gov Identifier: NCT00067899
Recruitment Status :
First Posted : September 8, 2003
Last Update Posted : June 19, 2013
National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK)
Information provided by (Responsible Party):
Maret Traber, National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK)
The purpose of this study is to determine if oxidative stress derived from cigarette smoking increases vitamin E requirements. The study will also assess the role of vitamin C in modulating vitamin E requirements. Vitamin E requirements will be assessed by measuring vitamin E in plasma as well as by measuring the excreted vitamin E metabolite in the urine.
Condition or disease
Drug: Vitamin E with and without Vitamin C
We will be investigating the fractional disappearance rate of tocopherols in cigarette smokers compared to nonsmokers. This will be accomplished by supplementing individuals with deuterium labeled alpha- and gamma-tocopherols. Quantification of plasma tocopherols as well as urinary metabolites, alpha- and gamma-carboxy ethyl hydroxychromanol, will be determined using liquid chromatography/mass spectrometry analysis. In addition, the role of vitamin C as it pertains to its influence on the fraction disappearance rate of vitamin E will also be evaluated.
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Layout table for eligibility information
Ages Eligible for Study:
18 Years to 35 Years (Adult)
Sexes Eligible for Study:
Accepts Healthy Volunteers:
non-smoking status or smokers (more than 1 pack per day)
age: 18-35 y
stable body weight, ranging between 80% and 130%,
maintenance of normal exercise and activity patterns