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Showing 1–24 of 767 matching trials from the live ClinicalTrials.gov search.
Local D1 index available.
Conditions
Prostate Cancer
Interventions
Vitamin D3, Placebo
Drug
Lead sponsor
VA Office of Research and Development
Federal
Eligibility
19 Years to 90 Years · Male only
Enrollment
130 participants
Healthy volunteers
Healthy volunteers not accepted
Timeline
2013 – 2020
U.S. locations
2
States / cities
Charleston, South Carolina
Withdrawn No phase listed Observational

Bariatric Surgery Outcomes

NCT01057784
Conditions
Morbid Obesity
Interventions
Bariatric surgery.
Procedure
Lead sponsor
University of California, Los Angeles
Other
Eligibility
Not listed
Healthy volunteers
Healthy volunteers not accepted
Timeline
2010 – 2014
U.S. locations
2
States / cities
Los Angeles, California
Conditions
Vitamin D Deficiency
Interventions
Vitamin D3
Dietary Supplement
Lead sponsor
Tufts University
Other
Eligibility
9 Years to 14 Years
Enrollment
691 participants
Healthy volunteers
Accepts healthy volunteers
Timeline
2011 – 2013
U.S. locations
1
States / cities
Boston, Massachusetts
Conditions
Healthy, no Evidence of Disease, Skin Cancer
Interventions
cholecalciferol
Drug
Lead sponsor
National Cancer Institute (NCI)
NIH
Eligibility
40 Years and older
Enrollment
25 participants
Healthy volunteers
Accepts healthy volunteers
Timeline
2012 – 2013
U.S. locations
1
States / cities
Tucson, Arizona
Conditions
Atherosclerosis
Interventions
Vitamin D3
Dietary Supplement
Lead sponsor
Rockefeller University
Other
Eligibility
18 Years to 85 Years
Enrollment
150 participants
Healthy volunteers
Healthy volunteers not accepted
Timeline
2009 – 2011
U.S. locations
1
States / cities
New York, New York
Completed No phase listed Observational Accepts healthy volunteers

A Study of Vitamin D in Subjects With Alopecia Areata

NCT01328678
Conditions
Alopecia Areata
Interventions
Not listed
Lead sponsor
Avera McKennan Hospital & University Health Center
Other
Eligibility
18 Years and older
Enrollment
10 participants
Healthy volunteers
Accepts healthy volunteers
Timeline
2009 – 2011
U.S. locations
1
States / cities
Sioux Falls, South Dakota
Withdrawn Not applicable Interventional Accepts healthy volunteers

Calcimimetics in Hypophosphatemic Rickets

NCT00844740
Conditions
Familial Hypophosphatemic Rickets
Interventions
Cinacalcet
Drug
Lead sponsor
Children's Mercy Hospital Kansas City
Other
Eligibility
5 Years to 21 Years
Healthy volunteers
Accepts healthy volunteers
Timeline
2009 – 2012
U.S. locations
1
States / cities
Kansas City, Missouri
Completed Not applicable Interventional Results available

Vitamin D Replacement After Kidney Transplant

NCT00748618
Conditions
Kidney Transplantation, Vitamin D Deficiency
Interventions
Standard vitamin D3 treatment, High dose vitamin D3 treatment
Dietary Supplement
Lead sponsor
University of Nebraska
Other
Eligibility
19 Years and older
Enrollment
116 participants
Healthy volunteers
Healthy volunteers not accepted
Timeline
2008 – 2023
U.S. locations
1
States / cities
Omaha, Nebraska
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
Systemic Lupus Erythematosus
Interventions
Vitamin D3 6000 IU, Vitamin D3 400 IU
Drug
Lead sponsor
National Institute of Allergy and Infectious Diseases (NIAID)
NIH
Eligibility
5 Years to 20 Years
Enrollment
7 participants
Healthy volunteers
Healthy volunteers not accepted
Timeline
2013 – 2014
U.S. locations
13
States / cities
Los Angeles, California • Palo Alto, California • San Francisco, California + 9 more
Completed Not applicable Interventional Accepts healthy volunteers Results available

A Large Randomized Trial of Vitamin D, Omega-3 Fatty Acids and Cognitive Decline

NCT01669915
Conditions
Cognitive Decline
Interventions
vitamin D3, omega-3 fatty acids (fish oil), Vitamin D3 placebo, Fish oil placebo
Dietary Supplement · Drug
Lead sponsor
Brigham and Women's Hospital
Other
Eligibility
60 Years to 92 Years
Enrollment
3,424 participants
Healthy volunteers
Accepts healthy volunteers
Timeline
2011 – 2021
U.S. locations
1
States / cities
Boston, Massachusetts
Completed Not applicable Interventional Accepts healthy volunteers

Comparative Effectiveness of Vitamin D and Repletion Strategies

NCT01524874
Conditions
Hypovitaminosis D, Insulin Resistance, Diabetes
Interventions
Vitamin D3
Dietary Supplement
Lead sponsor
Bastyr University
Other
Eligibility
18 Years to 65 Years
Enrollment
66 participants
Healthy volunteers
Accepts healthy volunteers
Timeline
2010 – 2011
U.S. locations
2
States / cities
Kailua-Kona, Hawaii • Kenmore, Washington
Conditions
X-linked Hypophosphatemia
Interventions
Placebo, KRN23
Drug
Lead sponsor
Kyowa Kirin Co., Ltd.
Industry
Eligibility
18 Years and older
Enrollment
42 participants
Healthy volunteers
Healthy volunteers not accepted
Timeline
2008 – 2013
U.S. locations
4
States / cities
New Haven, Connecticut • Indianapolis, Indiana • Durham, North Carolina + 1 more
Conditions
Healthy Volunteers
Interventions
Placebo, Canagliflozin
Drug
Lead sponsor
National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK)
NIH
Eligibility
18 Years and older
Enrollment
67 participants
Healthy volunteers
Healthy volunteers not accepted
Timeline
2014 – 2019
U.S. locations
1
States / cities
Bethesda, Maryland
Conditions
Vitamin D Deficiency, Hematopoietic Stem Cell Transplantation (HSCT)
Interventions
Oral Thin Film (OTF) Cholecalciferol (Vitamin D3)
Dietary Supplement
Lead sponsor
Children's Hospital Medical Center, Cincinnati
Other
Eligibility
Not listed
Enrollment
24 participants
Healthy volunteers
Healthy volunteers not accepted
Timeline
2021 – 2022
U.S. locations
1
States / cities
Cincinnati, Ohio
Active, not recruiting No phase listed Observational

X-linked Hypophosphatemia Disease Monitoring Program

NCT03651505
Conditions
X-linked Hypophosphatemia, Hypophosphatemic Rickets
Interventions
No intervention
Other
Lead sponsor
Ultragenyx Pharmaceutical Inc
Industry
Eligibility
Not listed
Enrollment
782 participants
Healthy volunteers
Healthy volunteers not accepted
Timeline
2018 – 2032
U.S. locations
24
States / cities
Birmingham, Alabama • Los Angeles, California • San Diego, California + 18 more
Completed Phase 2Phase 3 Interventional Results available

Vitamin D and Residual Beta-Cell Function in Type 1 Diabetes

NCT03046927
Conditions
Type 1 Diabetes
Interventions
Ergocalciferol, Placebo
Drug · Other
Lead sponsor
Benjamin U. Nwosu, MD
Other
Eligibility
10 Years to 21 Years
Enrollment
48 participants
Healthy volunteers
Healthy volunteers not accepted
Timeline
2017 – 2021
U.S. locations
1
States / cities
Worcester, Massachusetts
Conditions
Type 2 Diabetes Mellitus
Interventions
Vitamin D3 2000 international units daily, Vitamin C 500mg daily
Dietary Supplement
Lead sponsor
ProMedica Health System
Other
Eligibility
21 Years to 75 Years
Enrollment
37 participants
Healthy volunteers
Healthy volunteers not accepted
Timeline
2009 – 2010
U.S. locations
3
States / cities
Sylvania, Ohio • Toledo, Ohio
Completed Not applicable Interventional Accepts healthy volunteers

Vitamin D Deficiency: Bone Loss and Vascular Dysfunction

NCT00235586
Conditions
Postmenopausal Women
Interventions
10 vit. D deficient subjects take vit. D for 3 months.
Procedure
Lead sponsor
University of Kansas
Other
Eligibility
50 Years to 90 Years · Female only
Enrollment
40 participants
Healthy volunteers
Accepts healthy volunteers
Timeline
2004 – 2007
U.S. locations
1
States / cities
Kansas City, Kansas
Conditions
Obesity, Glucose Intolerance, Inflammation
Interventions
Placebo, Vitamin D 3 cholecalciferol
Dietary Supplement
Lead sponsor
University of Missouri-Columbia
Other
Eligibility
9 Years to 19 Years
Enrollment
44 participants
Healthy volunteers
Healthy volunteers not accepted
Timeline
2009 – 2013
U.S. locations
1
States / cities
Columbia, Missouri
Active, not recruiting Phase 2 Interventional Results available

Vitamin D and Physical Activity on Bone Health

NCT01419730
Conditions
Bone Metabolism Biomarkers, Bone Mineral Density, Physical Fitness
Interventions
Vitamin D3, Physical Activity
Drug · Behavioral
Lead sponsor
University of Rochester
Other
Eligibility
18 Years to 99 Years · Female only
Enrollment
191 participants
Healthy volunteers
Healthy volunteers not accepted
Timeline
2011 – 2026
U.S. locations
1
States / cities
Rochester, New York
Conditions
Infant, Very Low Birth Weight, Calcium Deficiency, Vitamin D Deficiency
Interventions
400 IU Cholecalciferol- Vitamin D Daily
Dietary Supplement
Lead sponsor
Medical University of South Carolina
Other
Eligibility
1 Day to 3 Days
Enrollment
68 participants
Healthy volunteers
Healthy volunteers not accepted
Timeline
2011 – 2013
U.S. locations
2
States / cities
Charleston, South Carolina
Conditions
Urinary Incontinence, Vitamin D Deficiency
Interventions
Vitamin D3 50,000 IU, Placebo
Dietary Supplement · Other
Lead sponsor
University of Alabama at Birmingham
Other
Eligibility
50 Years and older · Female only
Enrollment
243 participants
Healthy volunteers
Healthy volunteers not accepted
Timeline
2014 – 2017
U.S. locations
1
States / cities
Birmingham, Alabama
Active, not recruiting No phase listed Observational Accepts healthy volunteers

Bioavailability of Vitamin D(25(OH)D) and Omega-3 Fatty Acid (DHA) Enhanced Chicken

NCT05248737
Conditions
Nutrition, Healthy
Interventions
DHA/EPA fortified chicken plus Placebo, non-25(OH)D fortified chicken/eggs plus vitamin D3 supplement, non-DHA bio-enhanced chicken plus supplement DHA Omega-3, 25(OH)D bioenhanced chicken and eggs plus placebo, Dietary Supplement: DHA/EPA fortified eggs plus Placebo, non-DHA bio-enhanced eggs plus supplement DHA Omega-3, non-25(OH)D fortified chicken/eggs plus placebo
Dietary Supplement · Other
Lead sponsor
Cornell University
Other
Eligibility
18 Years to 35 Years
Enrollment
84 participants
Healthy volunteers
Accepts healthy volunteers
Timeline
2021 – 2026
U.S. locations
1
States / cities
Ithaca, New York