Vitamin E Pharmacokinetics and Biomarkers in Normal and Obese Women
Public ClinicalTrials.gov record NCT00862433. Field values are reproduced from the official study page; the official ClinicalTrials.gov record remains the source of truth for eligibility, enrollment, and contact information.
Data is sourced from official ClinicalTrials.gov public API records. Always review the official ClinicalTrials.gov record for the latest information.
Brief summary
Reproduced verbatim from the official ClinicalTrials.gov record. Not medical advice.
Background: * Vitamin E is an antioxidant that reduces the damaging effects of oxygen in the body. Most American men (90%) and women (96%) do not get enough vitamin E from their diets; however, the amount of vitamin E needed by the body has been studied only in men, not women. In addition, it is unknown whether another antioxidant, vitamin C, helps vitamin E in protecting the body. Because vitamin E is a fat-soluble vitamin, how much body fat a person has could affect the amount of vitamin E needed for protection. Objectives: This study has three arms to examine vitamin E requirements: * To determine the amount of fat required to get the best vitamin E absorption from a meal. * To determine the amount (i.e., best dose) of vitamin E that must be consumed before it can be measured in the blood. * To examine how vitamin E and vitamin C work together in the body, in conjunction with diet and vitamin supplements. Eligibility: * Arms 1 and 2: Women between the ages of 18 and 40 years who have a normal weight and body mass index (BMI) of 27 or less. * Arm 3: Women between the ages of 18 and 40 years who have a normal weight (BMI 27), who are overweight (BMI \> 27), or who are overweight (BMI \> 27) and have non insulin-dependent diabetes. Design: * Arm 1: Five studies, each lasting 1 month with 1 month off between studies (total study = 10 months). Participants will take 500 1,000 mg of vitamin C twice daily for 2 weeks before admission to the clinical center for 1 week. * Study 1: Participants will eat breakfast containing a known amount of fat, after which they will take a vitamin E pill as well as receive an IV injection of vitamin E. Other foods contain only negligible amounts of vitamin E. Blood and urine samples will measure levels of vitamin E and other substances. * Studies 2 5: Outpatient visits will consist of the same tests as in Study 1; however, the amount of fat in the breakfast will range from 0% to 40% in random order. During one of the studies, an adipose tissue biopsy will be collected to determine how much vitamin E is in the tissues. * Arm 2: Five studies, each lasting 1 month with 1 month off between studies (total study = 10 months). Preparation for Arm 2 is the same as in Arm 1. The proportion of fat, muscle, and water in the body will also be measured. * Study 1: Participants will eat breakfast containing 30% fat, after which they will take a vitamin E pill as well as receive an IV injection of vitamin E. Conditions and procedures are the same as in Arm 1. * Studies 2 5: Outpatient visits will consist of the same tests as in Study 1; however, the amount of vitamin E in the breakfast will range from 2 to 30 mg in random order. * Arm 3: Outpatient (2 to 6 weeks) and inpatient studies (4 to 6 weeks). * Outpatient study: Participants will take 500 1,000 mg of vitamin C daily and provide blood and urine samples, as well as an adipose tissue sample. * Inpatient studies: Two vitamin E inpatient studies. Before these begin, participants vitamin C blood levels will be reduced by means of a diet low in vitamin C. Blood tests will determine how quickly vitamin C leaves the body. Once the vitamin C level is reduced, the first vitamin E study will begin. Study A: The procedure for this study is the same as in Arm 2, Study 1. Study B: The procedure for this study is the same as in Study A, except that the participants blood vitamin C levels will be higher.
Study identification
- NCT ID
- NCT00862433
- Recruitment status
- Completed
- Study type
- Interventional
- Phase
- Phase 1
- Enrollment
- 50 participants
Conditions and interventions
Conditions
Eligibility (public fields only)
- Age range
- 18 Years to 55 Years
- Sex
- Female
- Healthy volunteers
- Healthy volunteers not accepted
This page does not interpret eligibility. Detailed inclusion and exclusion criteria are on the official ClinicalTrials.gov record.
Study timeline
- Start date
- Oct 9, 2014
- Primary completion
- Oct 20, 2016
- Completion
- May 2, 2022
- Last update posted
- Aug 31, 2026
2014 – 2022
United States locations
- U.S. sites
- 1
- U.S. states
- 1
- U.S. cities
- 1
| Facility | City | State | ZIP | Site status |
|---|---|---|---|---|
| National Institutes of Health Clinical Center | Bethesda | Maryland | 20892 | — |
Site contact phone numbers, emails, and investigator names are intentionally not displayed here. Open the official ClinicalTrials.gov record for site contact information.
About this trial record page
- What this page shows
- Public field values for ClinicalTrials.gov record NCT00862433, including study identification, conditions, interventions, eligibility (age, sex, healthy volunteer), timeline, and U.S. site list.
- What this page does not do
- No medical advice, eligibility judgments, treatment recommendations, study quality scoring, or AI-generated medical summaries. No site contact phone numbers, emails, or investigator names.
- Where the data comes from
- Sourced from the official ClinicalTrials.gov public API. The official record is the source of truth.
- Last refresh
- Last update posted Aug 31, 2026 · Synced Sep 21, 2026
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Open the official record
The complete protocol, eligibility criteria, and contact information for NCT00862433 live on ClinicalTrials.gov.