Vitamin D Intervention and Associated Changes in the Gut Microbiome and Vitamin D Levels in Healthy Adults

Association of Vitamin D Supplementation and Normal Dietary Intake of Vitamin D With Changes in the Gut Microbiome and Markers of Colorectal Cancer Risk

Status

UNKNOWN

Phases

Study type

Interventional

Source

ClinicalTrials.gov

Registry ID

NCT05387876

Acronym

VDMT

Enrollment

Registered

2022-05-24

Start date

2022-02-14

Completion date

2023-02-28

Last updated

2022-05-24

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Colorectal Cancer

Brief summary

Although dietary vitamin D supplementation has been used in the clinical setting for decades, the effect of supplementary vitamin D consumption on the structure of the microbiome has not been studied in humans in fine scale or with concomitant adjustment for dietary intake. Understanding the interaction of vitamin D with the microbiome in humans could lead to important advancements in the understanding of how vitamin D together with diet impacts the microbiome composition, and ultimately, risk of EOCRC. This study has the potential to lay the ground work for an adjunctive therapy to manipulate the microbiome to reduce risk of EOCRC. This proposed study is designed to evaluate the effect of vitamin D supplementation on the normal structure of the microbiome and data will not be used to diagnose, prevent, cure or treat disease.

Interventions

DIETARY_SUPPLEMENTVitamin D intervention

Nordic Naturals vitamin D gummies (1000 IUs/gummie), 4 gummies per day for 12 weeks

DIETARY_SUPPLEMENTPlacebo intervention

Organic gummie candies (no vitamin D), 4 gummies per day for 12 weeks

Study design

Allocation

RANDOMIZED

Intervention model

PARALLEL

Primary purpose

BASIC_SCIENCE

Masking

TRIPLE (Subject, Investigator, Outcomes Assessor)

Masking description

Participants, investigators and outcomes assessors are masked to intervention group assignments using a researcher outside the study that maintains the study codes and IDs

Intervention model description

Double blind placebo controlled randomized intervention of vitamin supplementation

Eligibility

Sex/Gender

ALL

Age

18 Years to 79 Years

Healthy volunteers

Yes

Inclusion criteria

* Adult 18 years or older

Exclusion criteria

* Women who are currently pregnant or breastfeeding * Use of antibiotics within the last 2 weeks * Use of supplementary vitamin D within the last month * Self-reported, pre-existing history of inflammatory bowel disease, heart disease or diabetes * Students under 18 * Tanning/sun exposure \> 60 min at a time in last 4 weeks * No phenobarbital, carbamazepine, spironolactone chronic therapy; or steroid use within the last 2 weeks * Severe allergy to ingredients found in supplements

Design outcomes

Primary

Measure	Time frame	Description
Microbiome alterations	12 weeks	Change in the microbiome structure and function

Countries

United States

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: Feb 4, 2026