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Evaluating Response to Vitamin D3 and K2 Supplementation in Healthcare Personnel
NCT07199829 · View on ClinicalTrials.gov ↗
Study Summary
The main purpose of this research study is to learn about the effects of supplemental vitamin D3 and vitamin K2 on blood levels and the gut microbial community, called the gut microbiome. There are many influences on blood levels of vitamin D and K to include your dietary intake, lifestyle behaviors (physical activity, sleep), genetic alterations in metabolism of these vitamins, and the gut microbial abundance and diversity. You will be asked to take one capsule containing vitamin D3 (125 mcg), vitamin K2 (180 mcg), a combination of vitamins D3 and K2 (same doses as previous), or a placebo powder for 90 days. You will also be asked to complete questionnaires, undergo body composition and blood pressure measurements, provide blood samples and a stool swab, all on 2 occasions about 3 - 4 months apart. By conducting this study, we aim to identify the frequency of common genetic alterations in vitamins D and K metabolism and establish the impact on the gut microbiome for the first time. Your participation in this study will last about 4 - 6 months and include up to 3 visits.
Conditions Studied
Interventions
- OTHER Placebo
- DIETARY_SUPPLEMENT Vitamin Arm 1
- DIETARY_SUPPLEMENT Vitamin Arm 2
- DIETARY_SUPPLEMENT Vitamin Arm 3
Study Locations (1)
Washington
- Madigan Army Medical Center — Tacoma
Trial Details
| Field | Value |
|---|---|
| Enrollment Target | 96 participants |
| Start Date | 2025-03-27 |
| Est. Completion | 2026-03 |
| Phase | NA |
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Full Details on ClinicalTrials.gov ↗What the Registry Record Tells You About NCT07199829
The ClinicalTrials.gov registry entry for NCT07199829 describes a study currently listed as recruiting. It is categorized as NA, which is the standard way researchers label where a study sits along the investigational pathway from early safety work through later efficacy and post-marketing evaluation. The registered enrollment target is 96 participants, a figure that helps gauge the scale of data the investigators plan to collect. The listed sponsor is Madigan Army Medical Center, which has 6 total studies on file at ClinicalTrials.gov, and sponsors are the parties responsible for study design, oversight, and regulatory filings.
The record links to 2 conditions, with Hypovitaminosis D appearing as the primary indexed condition, and to 4 interventions — of which Placebo is the first listed. Interventions can include drugs, devices, procedures, behavioral programs, or observational arms, and each is tracked as a separate registry field so that downstream queries can filter accurately. When a trial lists multiple interventions, it usually reflects a multi-arm design or a comparison protocol rather than a single treatment being tested in isolation. The brief summary published in the registry is the clearest source of protocol intent and should be read before drawing conclusions from any sidebar tags.
Geographic footprint matters for practical reasons: NCT07199829 reports 1 study location spanning 1 distinct geographic area — top geographies include Washington. A larger site network tends to correlate with broader recruitment capacity, but it does not imply anything about study quality, and site-level enrollment status can diverge from the overall registry status shown above. Every data point on this page comes from the public ClinicalTrials.gov dataset and is reproduced here for reference only; it is not a medical recommendation, an endorsement of the sponsor, or an invitation to enroll. Verify current status, eligibility criteria, and contact details directly at ClinicalTrials.gov, and discuss any participation decision with your own healthcare provider.
Frequently Asked Questions
What is clinical trial NCT07199829 about?
NCT07199829 is a clinical study titled "Evaluating Response to Vitamin D3 and K2 Supplementation in Healthcare Personnel". The main purpose of this research study is to learn about the effects of supplemental vitamin D3 and vitamin K2 on blood levels and the gut microbial community, called the gut microbiome. There are many influences on blood levels of vitamin D and K to include your dietary intake, lifestyle behaviors...
What is the current status of trial NCT07199829?
This trial is currently recruiting. It is a NA study. The enrollment target is 96 participants. The study started on 2025-03-27. Estimated completion is 2026-03.
What conditions does trial NCT07199829 study?
This clinical trial studies the following conditions: Hypovitaminosis D, Hypovitaminosis. These conditions were identified from the trial registry and reflect the primary focus areas of the research.
What interventions are being tested in trial NCT07199829?
The interventions under investigation include: Placebo (OTHER), Vitamin Arm 1 (DIETARY_SUPPLEMENT), Vitamin Arm 2 (DIETARY_SUPPLEMENT), Vitamin Arm 3 (DIETARY_SUPPLEMENT). Each intervention is being evaluated for safety and efficacy as part of this clinical study.
Who is sponsoring clinical trial NCT07199829?
This trial is sponsored by Madigan Army Medical Center, which has 6 total clinical trials registered on ClinicalTrials.gov. The sponsor is responsible for the study's design, funding, and regulatory compliance.
Where is trial NCT07199829 being conducted?
This trial has 1 study location across Washington. Contact the study sites directly through ClinicalTrials.gov for enrollment availability.
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