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Showing 1–24 of 55 matching trials from the live ClinicalTrials.gov search.
Local D1 index available.
Completed Phase 4 Interventional Accepts healthy volunteers

How Does Magnesium Status Influence Calcium Homeostasis?

NCT01593501
Conditions
Magnesium Deficiency, Calcium Metabolism Disorders
Interventions
vitamin D3
Dietary Supplement
Lead sponsor
University of Wisconsin, Madison
Other
Eligibility
30 Years to 75 Years · Female only
Enrollment
39 participants
Healthy volunteers
Accepts healthy volunteers
Timeline
2012 – 2014
U.S. locations
1
States / cities
Madison, Wisconsin
Conditions
Hemophilia A, Hemophilia B, Vitamin D Deficiency
Interventions
Vitamin D and calcium
Dietary Supplement
Lead sponsor
Virginia Commonwealth University
Other
Eligibility
2 Years to 21 Years · Male only
Enrollment
20 participants
Healthy volunteers
Healthy volunteers not accepted
Timeline
2010 – 2015
U.S. locations
1
States / cities
Richmond, Virginia
Completed No phase listed Observational Accepts healthy volunteers

Vitamin D and Pregnancy: Camden Study

NCT02032459
Conditions
Reproductive Effects, Pregnancy
Interventions
Not listed
Lead sponsor
Rowan University
Other
Eligibility
18 Years and older · Female only
Enrollment
1,141 participants
Healthy volunteers
Accepts healthy volunteers
Timeline
Started 2007
U.S. locations
1
States / cities
Stratford, New Jersey
Completed Not applicable Interventional Accepts healthy volunteers Results available

Evaluating the Effect of SOLIUS UV Light Source in Improving Vitamin D Status

NCT04780776
Conditions
Vitamin D Deficiency, Vitamin D Insufficiency
Interventions
UVB treatment, Sham comparator
Device
Lead sponsor
Boston University
Other
Eligibility
22 Years and older
Enrollment
69 participants
Healthy volunteers
Accepts healthy volunteers
Timeline
2022 – 2023
U.S. locations
1
States / cities
Boston, Massachusetts
Completed Not applicable Interventional Accepts healthy volunteers

A New Paradigm for Vitamin D Sufficiency

NCT02969850
Conditions
New Biomarkers for Measuring Vitamin D Level
Interventions
Vitamin D Supplementation, Placebo, Calcium
Dietary Supplement · Other
Lead sponsor
NYU Langone Health
Other
Eligibility
60 Years to 90 Years · Female only
Enrollment
444 participants
Healthy volunteers
Accepts healthy volunteers
Timeline
2016 – 2019
U.S. locations
1
States / cities
Mineola, New York
Completed No phase listed Observational Accepts healthy volunteers

Environmental Influences on Vitamin D Status

NCT00780247
Conditions
Vitamin D Deficiency
Interventions
Not listed
Lead sponsor
Creighton University
Other
Eligibility
18 Years to 60 Years
Enrollment
50 participants
Healthy volunteers
Accepts healthy volunteers
Timeline
2008
U.S. locations
1
States / cities
Anchorage, Alaska
Completed Not applicable Interventional Accepts healthy volunteers

Optimizing Vitamin D Status During Initial Military Training

NCT01617109
Conditions
Bone Health, Nutrition Status
Interventions
Ca/Vit D, Placebo
Dietary Supplement · Other
Lead sponsor
United States Army Research Institute of Environmental Medicine
Federal
Eligibility
17 Years to 42 Years
Enrollment
342 participants
Healthy volunteers
Accepts healthy volunteers
Timeline
2012 – 2018
U.S. locations
2
States / cities
Fort Sill, Oklahoma • San Antonio, Texas
Completed Phase 3 Interventional Accepts healthy volunteers Results available

Vitamin D Status of Pregnant Women and Their Children in Eau Claire, South Carolina

NCT00412087
Conditions
Vitamin D Deficiency, Pregnancy
Interventions
cholecalciferol (vitamin D3), cholecalciferol
Drug
Lead sponsor
Medical University of South Carolina
Other
Eligibility
16 Years to 45 Years · Female only
Enrollment
564 participants
Healthy volunteers
Accepts healthy volunteers
Timeline
2007 – 2009
U.S. locations
1
States / cities
Columbia, South Carolina
Conditions
Vitamin D Deficiency
Interventions
1,000 IU vitamin D2, placebo capsule, mushrooms, UVB-treated mushrooms, 400 IU vitamin D2, UVB-treated mushrooms, 1,000 IU vitamin D2
Dietary Supplement · Other
Lead sponsor
USDA, Western Human Nutrition Research Center
Federal
Eligibility
20 Years to 59 Years
Enrollment
48 participants
Healthy volunteers
Accepts healthy volunteers
Timeline
2010 – 2011
U.S. locations
1
States / cities
Davis, California
Conditions
Nutrition Status, Bone Health
Interventions
Calcium/Vitamin D, Placebo
Dietary Supplement
Lead sponsor
United States Army Research Institute of Environmental Medicine
Federal
Eligibility
17 Years and older
Enrollment
380 participants
Healthy volunteers
Accepts healthy volunteers
Timeline
2015 – 2016
U.S. locations
1
States / cities
Parris Island, South Carolina
Conditions
Sepsis, Severe Sepsis, End Organ Damage, Multi Organ Failure
Interventions
vitamin D3, Placebo
Drug
Lead sponsor
Massachusetts General Hospital
Other
Eligibility
18 Years to 80 Years
Healthy volunteers
Healthy volunteers not accepted
Timeline
2017 – 2022
U.S. locations
1
States / cities
Boston, Massachusetts
Completed Not applicable Interventional Accepts healthy volunteers

Impact of Vitamin D Status on Bones in Breastfed Infants

NCT00697294
Conditions
Vitamin D Deficiency
Interventions
Tri-Vi-Sol
Dietary Supplement
Lead sponsor
Baylor College of Medicine
Other
Eligibility
Up to 2 Hours
Enrollment
80 participants
Healthy volunteers
Accepts healthy volunteers
Timeline
2008 – 2011
U.S. locations
3
States / cities
Houston, Texas
Completed No phase listed Observational Accepts healthy volunteers

Vitamin D Status and the Adequacy of Vitamin D Intake in Early Preterm Infants

NCT01793402
Conditions
Hypovitaminosis D
Interventions
Not listed
Lead sponsor
Children's Hospital Medical Center, Cincinnati
Other
Eligibility
1 Day to 1 Week
Enrollment
120 participants
Healthy volunteers
Accepts healthy volunteers
Timeline
2010 – 2012
U.S. locations
1
States / cities
Cincinnati, Ohio
Recruiting Not applicable Interventional Accepts healthy volunteers

A Study of a Dietary Supplement on Serum Biomarkers in Children

NCT07385144
Conditions
Nutritional Status, Serum Biomarkers
Interventions
Dietary Supplement (Kids Multi & Omegas)
Dietary Supplement
Lead sponsor
SF Research Institute, Inc.
Network
Eligibility
4 Years to 15 Years
Enrollment
30 participants
Healthy volunteers
Accepts healthy volunteers
Timeline
2026
U.S. locations
1
States / cities
San Francisco, California
Completed Phase 3 Interventional Accepts healthy volunteers Results available

Preventing Health Disparities During Pregnancy Through Vitamin D Supplementation

NCT01932788
Conditions
Vitamin D3 Deficiency
Interventions
Vitamin D3 4000 IU in gummy form, Placebo gummy vitamin
Drug
Lead sponsor
Medical University of South Carolina
Other
Eligibility
18 Years to 45 Years · Female only
Enrollment
342 participants
Healthy volunteers
Accepts healthy volunteers
Timeline
2013 – 2018
U.S. locations
1
States / cities
Charleston, South Carolina
Completed No phase listed Observational Accepts healthy volunteers

Vitamin D Status and Metabolism in Human Pregnancy

NCT03051867
Conditions
Pregnancy
Interventions
Not listed
Lead sponsor
Cornell University
Other
Eligibility
21 Years and older · Female only
Enrollment
47 participants
Healthy volunteers
Accepts healthy volunteers
Timeline
2009 – 2011
U.S. locations
1
States / cities
Ithaca, New York
Conditions
Vitamin D Deficiency, Vitamin D Insufficiency
Interventions
Vitamin D, Placebo, Standard of Care
Dietary Supplement · Other
Lead sponsor
Johns Hopkins University
Other
Eligibility
18 Years to 64 Years
Enrollment
70 participants
Healthy volunteers
Healthy volunteers not accepted
Timeline
2017
U.S. locations
1
States / cities
Baltimore, Maryland
Conditions
Hypovitaminosis D
Interventions
Cholecalciferol, Placebo
Dietary Supplement
Lead sponsor
Massachusetts General Hospital
Other
Eligibility
18 Years to 100 Years
Healthy volunteers
Healthy volunteers not accepted
Timeline
2015 – 2017
U.S. locations
1
States / cities
Boston, Massachusetts
Conditions
Determine Effect of Vitamin D on Bone Health in Elderly African American Women
Interventions
Vitamin D 3, placebo
Dietary Supplement · Other
Lead sponsor
Winthrop University Hospital
Other
Eligibility
60 Years and older · Female only
Enrollment
260 participants
Healthy volunteers
Accepts healthy volunteers
Timeline
2010 – 2016
U.S. locations
1
States / cities
Mineola, New York
Completed No phase listed Observational Accepts healthy volunteers

Environmental & Genetic Influences on Vitamin D Status

NCT01208636
Conditions
Vitamin D Deficiency
Interventions
Not listed
Lead sponsor
Creighton University
Other
Eligibility
18 Years to 60 Years
Enrollment
40 participants
Healthy volunteers
Accepts healthy volunteers
Timeline
2010
U.S. locations
1
States / cities
Omaha, Nebraska
Completed Not applicable Interventional Accepts healthy volunteers

Prevention of Vitamin D Deficiency

NCT00494104
Conditions
Vitamin D Deficiency
Interventions
Vitamin D drops, 200 or 400 or 600 IU/day or 800 IU/day
Dietary Supplement
Lead sponsor
Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD)
NIH
Eligibility
3 Weeks to 5 Weeks
Enrollment
398 participants
Healthy volunteers
Accepts healthy volunteers
Timeline
2006 – 2011
U.S. locations
1
States / cities
Coralville, Iowa
Completed Not applicable Interventional Results available

Improving Vitamin D Status in Home-bound Elders

NCT01410084
Conditions
Vitamin D Deficiency, Accidental Falls
Interventions
Vitamin D3, Vitamin E
Dietary Supplement
Lead sponsor
Wake Forest University Health Sciences
Other
Eligibility
65 Years and older
Enrollment
68 participants
Healthy volunteers
Healthy volunteers not accepted
Timeline
2010 – 2011
U.S. locations
1
States / cities
Winston-Salem, North Carolina
Completed Phase 4 Interventional Accepts healthy volunteers

UVB Light and Sunscreen

NCT00818467
Conditions
Vitamin D Status
Interventions
Tanning spray, UVB
Other
Lead sponsor
Creighton University
Other
Eligibility
19 Years to 50 Years
Enrollment
50 participants
Healthy volunteers
Accepts healthy volunteers
Timeline
2008 – 2009
U.S. locations
1
States / cities
Omaha, Nebraska
Conditions
Vitamin D Deficiency, Osteoporosis
Interventions
Vitamin D, placebo
Drug
Lead sponsor
University of Wisconsin, Madison
Other
Eligibility
55 Years and older
Enrollment
96 participants
Healthy volunteers
Healthy volunteers not accepted
Timeline
2001 – 2004
U.S. locations
1
States / cities
Madison, Wisconsin