FemalesPM-VitCNCT07109115
The Effects of Vitamin C on Acute-Exercise in Postmenopausal Females
A study testing Vitamin C (Ascorbic Acid) in people with Females and Males, run by University of Virginia at 1 site in United States.
Trial summary
This study is looking at whether vitamin C can help improve oxidative stress and blood vessel health in females after menopause. We will see if taking different amounts of vitamin C for a few days changes how the body handles stress from exercise. Read more about this study
- Who is it for?
- Ages 45 years and olderHealthy volunteers can take part
- What is being tested?
- Vitamin C (Ascorbic Acid)
- Could I receive a placebo?
- Yes, some participants may receive a placebo
- How many people
- 1 participants
- Where
- 1 siteUnited States
- Study dates
- 1 Sep 2025to 1 Jul 2026
- Phase
- Interventional
- Are there results?
- None posted in the registry
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 45 years and older
- All sexes
- Healthy volunteers accepted
- Adult, Older adult
Who may be able to join
- Post-menopausal (for females; defined as no menstrual cycle for 1-year)
- Sedentary (<150min of moderate-intensity exercise per week or not engaged in a regular exercise program)
- Non-smoking
- Weight stable (+/-3 kg over the past 3 months)
Who cannot join
- Overt CVD
- Any condition or medication contraindicating safe exercise
- Hormone replacement therapy (last 3-months)
- Use of vasoactive medications (e.g., calcium channel blockers, statins, ACE inhibitors, ARBs, nitrates, alpha-/beta-blockers, diuretics), diabetes, or unstable medication regimens
- Diabetes
- Oral antibiotic use within previous four weeks
Show all 9Show fewer
- Oral disease or poor oral health as determined by the Oral Health Questionnaire
- Using an antibacterial mouthwash or a mouthwash containing chlorhexidine and unwilling to discontinue use
- Cancer diagnosis
Trial locations and contacts
1 site in 1 country.
United States1 site
Student Health and Wellness Building - Department of Kinesiology
Charlottesville, Virginia, 22903
About this study
Official title: The Effects of Vitamin C on Exercise-Induced Oxidative Stress in Postmenopausal Females
This study is looking at whether vitamin C can help improve oxidative stress and blood vessel health in females after menopause. We will see if taking different amounts of vitamin C for a few days changes how the body handles stress from exercise. This could lead to safer ways to protect females from heart disease without using hormone therapy.
Read the detailed description
Cardiovascular disease (CVD) remains the leading cause of death in the United States. After menopause, females face a significantly increased risk of CVD due to declines in estrogen, which negatively impact nitric oxide (NO) production and vascular health. This coincides with an increase in reactive oxygen species (ROS), leading to an imbalance in redox signaling that may blunt beneficial adaptations to exercise.
Vitamin C (ascorbic acid) is a potent antioxidant that may restore redox balance and endothelial function. However, most studies have been conducted in males using high doses that may suppress beneficial ROS signaling. In contrast, this trial focuses on the dose-response effects of short-term vitamin C supplementation (200 mg, 500 mg, and 1000 mg/day for 3 days) on ROS/NO balance, both at rest and in response to acute exercise, in PMF versus age-matched males.
The study includes 15 sedentary PMF and 15 sedentary age-matched males, ages 45 and older. Participants complete 5-6 total study visits: one baseline/screening visit and four intervention visits in a randomized crossover design. Each intervention visit consists of 3 days of supplementation followed by fasting blood draws, vascular testing, and a 200-kcal high-intensity exercise bout on a cycle ergometer.
- Conditions
- Females, Males, Menopause, Sedentary, Healthy Participants
- Being tested
- Vitamin C (Ascorbic Acid)
- Keywords
- Vitamin C, Postmenopausal Females, Exercise, Oxidative Stress, Vascular Health
- Medical subject headings
- Sedentary Behavior, Motor Activity
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Vitamin C (Ascorbic Acid)Dietary supplement
Subjects will be supplemented with the following vitamin C doses: 0mg, 200mg, 500mg, 1000mg.
| Study group | Role | What they receive |
|---|---|---|
| Active Comparator 1: 200mg vitamin C | Experimental | Subjects will supplement with 200mg of vitamin C 2x a day for 3 days. 100mg will be taken in the morning and 100mg in the evening. On the 3rd day, subjects will be scheduled to return for post-supplementation testing and be instructed to take a full 200mg dose 30-minutes prior to arriving. Receives: Dietary Supplement: Vitamin C (Ascorbic Acid) |
| Active Comparator 1: 500mg vitamin C | Experimental | Subjects will supplement with 500mg of vitamin C 2x a day for 3 days. Subjects will take half the dose in the morning and half the dose in the evening. On the 3rd day, subjects will be scheduled to return for post-supplementation testing and be instructed to take a full dose 30-minutes prior to arriving. Receives: Dietary Supplement: Vitamin C (Ascorbic Acid) |
| Active Comparator 1: 1000mg vitamin C | Experimental | Subjects will supplement with 1000mg of vitamin C 2x a day for 3 days. Subjects will take half the dose in the morning and half the dose in the evening. On the 3rd day, subjects will be scheduled to return for post-supplementation testing and be instructed to take a full dose 30-minutes prior to arriving. Receives: Dietary Supplement: Vitamin C (Ascorbic Acid) |
| Placebo Comparator 1: 0mg Vitamin C | Placebo comparator | Subjects will supplement with 0mg of vitamin C 2x a day for 3 days. Subjects will take half the dose in the morning and half the dose in the evening. On the 3rd day, subjects will be scheduled to return for post-supplementation testing and be instructed to take a full dose 30-minutes prior to arriving. Receives: Dietary Supplement: Vitamin C (Ascorbic Acid) |
What is being measured
The primary outcome is the main question the study is designed to answer.
Flow-Mediated Dilation (FMD%) - Brachial Artery Endothelial Function
Brachial artery endothelial function will be measured by flow-mediated dilation (FMD) in each participant 5x (at baseline and after 0mg (placebo) 200mg, 500mg, and 1000mg of vitamin C). Participants will be placed in a supine position with their left forearm slightly extended and supinated with legs straight. The brachial artery will be imaged using a high-resolution 7.5MHz linear array transducer at rest, during 5 minutes of forearm occlusion via cuff inflation (250mmHg), and continuously for 2 minutes post-occlusion; an EKG trigger will be used to capture images during end-diastole of the cardiac cycle.
Measured: 5x: Baseline/un-supplemented; after 3-days of 200mg of vitamin C supplementation; after 3-days of 500mg of vitamin C supplementation; after 3-days of 1000mg of vitamin C supplementation; after 3-days of 0mg of vitamin C/placebo supplementation
Basal ROS Concentrations - plasma 8-Isoprostane (8-iso) and malondialdehyde (MDA)
A venous blood sample will be collected from a vein in the antecubital fossa. Plasma will be separated out and stored at -80C until concentrations of 8-Isoprostane (8-iso) and malondialdehyde (MDA) are measured via commerically available ELISA kits. ROS concentrations will be measured at 5x points: at baseline and after 0mg (placebo), 200mg, 500mg, and 1000mg of vitamin C
Measured: baseline and after 0mg/placebo, 200mg, 500mg, and 1000mg dose of vitamin C for 3-days each
Resting ROS/NO Balance - plasma N-oxides (nitrite and nitrate)
Venous blood samples will be collected from an antecubital fossa vein. Plasma will be separated out and stored at -80C until analysis. Plasma N-oxides (nitrite and nitrate) will be evaluated from the plasma via ozone-based chemiluminescence using a Sievers NOA model 280i. The N-oxides will be compared with the basal ROS also measured to calculate a ROS/NO balance.
Measured: Baseline and after 3-days of placebo, 200mg, 500mg, and 1000mg doses of vitamin C
Exercise-Induced ROS (plasma 8-Isoprostane (8-iso) and malondialdehyde (MDA)) and NO (plasma nitrate and nitrite)
An intravenous catheter will be placed into a vein in the antecubital fossa. Participants will complete 4 high-intensity exercise sessions (~200kcals). Each exercise session will be after 3-days of vitamin C supplementation (0mg/placebo, 200mg, 500mg, and 1000mg). Blood will be collected immediately before, immediately after, 15-min after, and 30-min after exercise. Plasma will be separated out and used to evaluate the changes in ROS (plasma 8-Isoprostane (8-iso) and malondialdehyde (MDA)) and NO (plasma nitrate and nitrite) from baseline/rest.
Measured: 16x points: 4 exercise session with blood will be collected immediately before, immediately after, 15-min after, and 30-min after exercise
Secondary outcomes (7)
Vitamin C
Blood samples will be collected to evaluate compliance. We will measure vitamin C concentrations after each supplementation phase.
Measured: 5x points over 5-6 weeks: (1) baseline/unsupplemented and after 3-days of (2) 0mg/placebo, (3) 200mg, (4) 500mg, and (5) 1000mg of vitamin C supplementation
Oral Nitrate Reducing Capacity
Assessment of the oral microbiome's ability to reduce nitrate to nitrite. This will be measured through an unstimulated saliva sample and a rinse of a standard nitrate solution.
Measured: 5x points over 5-6 weeks: (1) baseline/unsupplemented and after 3-days of (2) 0mg/placebo, (3) 200mg, (4) 500mg, and (5) 1000mg of vitamin C supplementation
Pulse Wave Analysis and Velocity
Brachial artery blood pressures will be obtained using a standard sphygmomanometer. Aortic blood pressures will be obtained using applanation tonometry (SphygmoCor version 8.0, AtCor Medical).
Measured: 5x points over 5-6 weeks: (1) baseline/unsupplemented and after 3-days of (2) 0mg/placebo, (3) 200mg, (4) 500mg, and (5) 1000mg of vitamin C supplementation
Microvascular Function
Participants will remain in a supine position with their left or right forearm slight extended and supinated. The cuff used for FMD will remain in place and two circular discs will be placed on the participants extended forearm. A laser Doppler imager (Moor Instruments - FLPI2) will be positioned directly over the participants forearm to measure skin blood flow in three different ways: microvascular flow mediated dilation, acetylcholine, and local thermal heating.
Measured: 5x points over 5-6 weeks: (1) baseline/unsupplemented and after 3-days of (2) 0mg/placebo, (3) 200mg, (4) 500mg, and (5) 1000mg of vitamin C supplementation
Exercise Capacity
Participants will exercise using an incremental cycle ergometer protocol with increasing power output until volitional exhaustion is reached. The power output will increase in 3-minute stages, where blood is collected before the start of exercise and at the end of each stage. The LT will be established by analyzing the blood lactate-power output relationship. VO2 peak will be defined as the highest one min value attained during the test.
Measured: Baseline only
Tissue Perfusion (NIRS)
Tissue oxygenation will be captured noninvasively using non-invasive, near-infrared spectrometry (NIRS, PortaMon, Artinis Medical Systems B.V., The Netherlands) positioned on the gastrocnemius (calf) or vastus lateralis (quad) muscle during the VO2/LT test and during each Experimental Visit (HIE sessions).
Measured: 5x points over 5-6 weeks: (1) baseline/unsupplemented and after 3-days of (2) 0mg/placebo, (3) 200mg, (4) 500mg, and (5) 1000mg of vitamin C supplementation
Central Hemodynamics (Physioflow)
: Measures of central hemodynamics (cardiac output, etc.) will be non-invasively captured throughout the VO2/LT test and during each Experimental Visit (HIE sessions). Using electrodes placed on the participant's body and the principles of signal morphology impedance cardiography PhysioFlow provides estimates of central cardiac measures at rest and during exercise non-invasively.
Measured: 5x points over 5-6 weeks: (1) baseline/unsupplemented and after 3-days of (2) 0mg/placebo, (3) 200mg, (4) 500mg, and (5) 1000mg of vitamin C supplementation
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted7 Aug 2025
- Study start1 Sep 2025
- Primary completion1 Jul 2026
- Study completion1 Jul 2026
Why it stopped: Insufficient funds and study personal to complete the trial when the primary grant holder and coordinator resigned from UVA.
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for FemalesStudies of the same condition, open and under way.
- More trials run by University of VirginiaThe sponsor's other registered studies.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase N/A
- Primary purpose
- Other
- Allocation
- Randomised
- Intervention model
- Crossover
- Masking
- Quadruple blind
- Who is masked
- Participant, Care provider, Investigator, Outcomes assessor
- Enrolment
- 1 participants (actual)
Sponsor and investigators
- Lead sponsor
- University of Virginia
- Sponsor type
- University, hospital or other
- Responsible party
- Principal investigator, Jason Allen, University of Virginia
- Investigators
- Jason Allen, PhD, Principal investigator, UVA
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT07109115
- Sponsor's protocol ID
- 302767
- Acronym
- PM-VitC
- Status last verified
- Jul 2026
- First submitted
- 23 Jul 2025
- Last updated
- 17 Jul 2026
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- No
Study at a glance
From the registry record, last updated by the sponsor on 17 Jul 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- The Effects of Vitamin C on Exercise-Induced Oxidative Stress in Postmenopausal Females
- ClinicalTrials.gov ID
- NCT07109115
- Acronym / sponsor ID
- PM-VitC / 302767
- Conditions
- Females, Males, Menopause, Sedentary, Healthy Participants
- Keywords
- Vitamin C, Postmenopausal Females, Exercise, Oxidative Stress, Vascular Health
- Study type
- Interventional
- Recruitment status
- TerminatedReason stopped: Insufficient funds and study personal to complete the trial when the primary grant holder and coordinator resigned from UVA.
- Enrolment
- 1 participants (actual)
- Lead sponsor
- University of VirginiaUniversity, hospital or other
- Study start
- 1 Sep 2025 (actual)
- Primary completion
- 1 Jul 2026 (actual)
- Study completion
- 1 Jul 2026 (actual)
- First posted
- 7 Aug 2025 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
This study is looking at whether vitamin C can help improve oxidative stress and blood vessel health in females after menopause. We will see if taking different amounts of vitamin C for a few days changes how the body handles stress from exercise. This could lead to safer ways to protect females from heart disease without using hormone therapy.
Detailed description
Cardiovascular disease (CVD) remains the leading cause of death in the United States. After menopause, females face a significantly increased risk of CVD due to declines in estrogen, which negatively impact nitric oxide (NO) production and vascular health. This coincides with an increase in reactive oxygen species (ROS), leading to an imbalance in redox signaling that may blunt beneficial adaptations to exercise.
Vitamin C (ascorbic acid) is a potent antioxidant that may restore redox balance and endothelial function. However, most studies have been conducted in males using high doses that may suppress beneficial ROS signaling. In contrast, this trial focuses on the dose-response effects of short-term vitamin C supplementation (200 mg, 500 mg, and 1000 mg/day for 3 days) on ROS/NO balance, both at rest and in response to acute exercise, in PMF versus age-matched males.
The study includes 15 sedentary PMF and 15 sedentary age-matched males, ages 45 and older. Participants complete 5-6 total study visits: one baseline/screening visit and four intervention visits in a randomized crossover design. Each intervention visit consists of 3 days of supplementation followed by fasting blood draws, vascular testing, and a 200-kcal high-intensity exercise bout on a cycle ergometer.
Study design
- Primary purpose
- Other
- Allocation
- Randomised
- Intervention model
- Crossover
- Masking
- Quadruple blind (participant, care provider, investigator, outcomes assessor)
- Number of arms
- 4
| Arm | Type | Receives |
|---|---|---|
| Active Comparator 1: 200mg vitamin C | Experimental | Dietary Supplement: Vitamin C (Ascorbic Acid)Subjects will supplement with 200mg of vitamin C 2x a day for 3 days. 100mg will be taken in the morning and 100mg in the evening. On the 3rd day, subjects will be scheduled to return for post-supplementation testing and be instructed to take a full 200mg dose 30-minutes prior to arriving. |
| Active Comparator 1: 500mg vitamin C | Experimental | Dietary Supplement: Vitamin C (Ascorbic Acid)Subjects will supplement with 500mg of vitamin C 2x a day for 3 days. Subjects will take half the dose in the morning and half the dose in the evening. On the 3rd day, subjects will be scheduled to return for post-supplementation testing and be instructed to take a full dose 30-minutes prior to arriving. |
| Active Comparator 1: 1000mg vitamin C | Experimental | Dietary Supplement: Vitamin C (Ascorbic Acid)Subjects will supplement with 1000mg of vitamin C 2x a day for 3 days. Subjects will take half the dose in the morning and half the dose in the evening. On the 3rd day, subjects will be scheduled to return for post-supplementation testing and be instructed to take a full dose 30-minutes prior to arriving. |
| Placebo Comparator 1: 0mg Vitamin C | Placebo comparator | Dietary Supplement: Vitamin C (Ascorbic Acid)Subjects will supplement with 0mg of vitamin C 2x a day for 3 days. Subjects will take half the dose in the morning and half the dose in the evening. On the 3rd day, subjects will be scheduled to return for post-supplementation testing and be instructed to take a full dose 30-minutes prior to arriving. |
Who may qualify
- Ages
- 45 years and older
- Sex
- All
- Healthy volunteers
- Accepted
- Age groups
- Adult, Older adult
Key inclusion criteria (4 listed)
- Post-menopausal (for females; defined as no menstrual cycle for 1-year)
- Sedentary (<150min of moderate-intensity exercise per week or not engaged in a regular exercise program)
- Non-smoking
- Weight stable (+/-3 kg over the past 3 months)
Key exclusion criteria (9 listed)
- Overt CVD
- Any condition or medication contraindicating safe exercise
- Hormone replacement therapy (last 3-months)
- Use of vasoactive medications (e.g., calcium channel blockers, statins, ACE inhibitors, ARBs, nitrates, alpha-/beta-blockers, diuretics), diabetes, or unstable medication regimens
- Diabetes
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| Vitamin C (Ascorbic Acid)Subjects will be supplemented with the following vitamin C doses: 0mg, 200mg, 500mg, 1000mg. | Dietary supplement | Active Comparator 1: 1000mg vitamin C, Active Comparator 1: 200mg vitamin C, Active Comparator 1: 500mg vitamin C, Placebo Comparator 1: 0mg Vitamin C |
Primary outcome
Flow-Mediated Dilation (FMD%) - Brachial Artery Endothelial Function
Time frame: 5x: Baseline/un-supplemented; after 3-days of 200mg of vitamin C supplementation; after 3-days of 500mg of vitamin C supplementation; after 3-days of 1000mg of vitamin C supplementation; after 3-days of 0mg of vitamin C/placebo supplementation
Brachial artery endothelial function will be measured by flow-mediated dilation (FMD) in each participant 5x (at baseline and after 0mg (placebo) 200mg, 500mg, and 1000mg of vitamin C). Participants will be placed in a supine position with their left forearm slightly extended and supinated with legs straight. The brachial artery will be imaged using a high-resolution 7.5MHz linear array transducer at rest, during 5 minutes of forearm occlusion via cuff inflation (250mmHg), and continuously for 2 minutes post-occlusion; an EKG trigger will be used to capture images during end-diastole of the cardiac cycle.
Basal ROS Concentrations - plasma 8-Isoprostane (8-iso) and malondialdehyde (MDA)
Time frame: baseline and after 0mg/placebo, 200mg, 500mg, and 1000mg dose of vitamin C for 3-days each
A venous blood sample will be collected from a vein in the antecubital fossa. Plasma will be separated out and stored at -80C until concentrations of 8-Isoprostane (8-iso) and malondialdehyde (MDA) are measured via commerically available ELISA kits. ROS concentrations will be measured at 5x points: at baseline and after 0mg (placebo), 200mg, 500mg, and 1000mg of vitamin C
Resting ROS/NO Balance - plasma N-oxides (nitrite and nitrate)
Time frame: Baseline and after 3-days of placebo, 200mg, 500mg, and 1000mg doses of vitamin C
Venous blood samples will be collected from an antecubital fossa vein. Plasma will be separated out and stored at -80C until analysis. Plasma N-oxides (nitrite and nitrate) will be evaluated from the plasma via ozone-based chemiluminescence using a Sievers NOA model 280i. The N-oxides will be compared with the basal ROS also measured to calculate a ROS/NO balance.
Exercise-Induced ROS (plasma 8-Isoprostane (8-iso) and malondialdehyde (MDA)) and NO (plasma nitrate and nitrite)
Time frame: 16x points: 4 exercise session with blood will be collected immediately before, immediately after, 15-min after, and 30-min after exercise
An intravenous catheter will be placed into a vein in the antecubital fossa. Participants will complete 4 high-intensity exercise sessions (~200kcals). Each exercise session will be after 3-days of vitamin C supplementation (0mg/placebo, 200mg, 500mg, and 1000mg). Blood will be collected immediately before, immediately after, 15-min after, and 30-min after exercise. Plasma will be separated out and used to evaluate the changes in ROS (plasma 8-Isoprostane (8-iso) and malondialdehyde (MDA)) and NO (plasma nitrate and nitrite) from baseline/rest.
7 secondary outcomes
Vitamin C
Time frame: 5x points over 5-6 weeks: (1) baseline/unsupplemented and after 3-days of (2) 0mg/placebo, (3) 200mg, (4) 500mg, and (5) 1000mg of vitamin C supplementation
Oral Nitrate Reducing Capacity
Time frame: 5x points over 5-6 weeks: (1) baseline/unsupplemented and after 3-days of (2) 0mg/placebo, (3) 200mg, (4) 500mg, and (5) 1000mg of vitamin C supplementation
Pulse Wave Analysis and Velocity
Time frame: 5x points over 5-6 weeks: (1) baseline/unsupplemented and after 3-days of (2) 0mg/placebo, (3) 200mg, (4) 500mg, and (5) 1000mg of vitamin C supplementation
Microvascular Function
Time frame: 5x points over 5-6 weeks: (1) baseline/unsupplemented and after 3-days of (2) 0mg/placebo, (3) 200mg, (4) 500mg, and (5) 1000mg of vitamin C supplementation
Exercise Capacity
Time frame: Baseline only
Tissue Perfusion (NIRS)
Time frame: 5x points over 5-6 weeks: (1) baseline/unsupplemented and after 3-days of (2) 0mg/placebo, (3) 200mg, (4) 500mg, and (5) 1000mg of vitamin C supplementation
Central Hemodynamics (Physioflow)
Time frame: 5x points over 5-6 weeks: (1) baseline/unsupplemented and after 3-days of (2) 0mg/placebo, (3) 200mg, (4) 500mg, and (5) 1000mg of vitamin C supplementation
Results and safety
The study was stopped early (reason given: Insufficient funds and study personal to complete the trial when the primary grant holder and coordinator resigned from UVA.). Results are not available in the source record.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 17 Jul 2026.
- Individual participant dataSharing planned: No
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Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part. This study is not recruiting at the moment.
Jason Allen, PhD principal investigator
UVA
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A study testing Vitamin C (Ascorbic Acid) in people with Females and Males, run by University of Virginia at 1 site in United States.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 4 inclusion and 9 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: stopped early, as of the sponsor's last update on 17 Jul 2026. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 1 site in United States. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. Some participants in this study may receive a placebo. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
Are results available for this study?
The study was stopped early (reason given: Insufficient funds and study personal to complete the trial when the primary grant holder and coordinator resigned from UVA.). Results are not available in the source record.
How can a doctor refer a patient or contact the research team?
The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Flow-Mediated Dilation (FMD%) - Brachial Artery Endothelial Function (time frame: 5x: Baseline/un-supplemented; after 3-days of 200mg of vitamin C supplementation; after 3-days of 500mg of vitamin C supplementation; after 3-days of 1000mg of vitamin C supplementation; after 3-days of 0mg of vitamin C/placebo supplementation). The study lists 4 primary outcomes in all. It is what the study was designed to measure, not a finding.
Where can I read the original study information?
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 17 Jul 2026.