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Showing 1–24 of 575 matching trials from the live ClinicalTrials.gov search.
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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
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
Conditions
Prostate Cancer
Interventions
calcitriol, dexamethasone, protein expression analysis, laboratory biomarker analysis
Dietary Supplement · Drug · Genetic + 1 more
Lead sponsor
Roswell Park Cancer Institute
Other
Eligibility
Up to 120 Years · Male only
Enrollment
18 participants
Healthy volunteers
Healthy volunteers not accepted
Timeline
2006 – 2010
U.S. locations
1
States / cities
Buffalo, New York
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
Precancerous/Nonmalignant Condition, Prostate Cancer
Interventions
calcitriol, observation
Dietary Supplement · Procedure
Lead sponsor
Rutgers, The State University of New Jersey
Other
Eligibility
18 Years and older · Male only
Enrollment
12 participants
Healthy volunteers
Healthy volunteers not accepted
Timeline
2004 – 2011
U.S. locations
5
States / cities
East Brunswick, New Jersey • Morristown, New Jersey • New Brunswick, New Jersey + 1 more
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
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
Conditions
Secondary Hyperparathyroidism, Chronic Kidney Disease
Interventions
Cinacalcet, active vitamin D analogue
Other
Lead sponsor
University of Colorado, Denver
Other
Eligibility
18 Years and older
Enrollment
92 participants
Healthy volunteers
Healthy volunteers not accepted
Timeline
2010 – 2011
U.S. locations
1
States / cities
Lynchburg, Virginia
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
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
Conditions
Graves Disease, Graves' Disease, Hyperthyroidism
Interventions
Ergocalciferol 50,000 IU, Methimazole
Drug
Lead sponsor
Northwell Health
Other
Eligibility
9 Years to 17 Years
Enrollment
30 participants
Healthy volunteers
Healthy volunteers not accepted
Timeline
2025 – 2027
U.S. locations
1
States / cities
New Hyde Park, New York
Completed Not applicable Interventional Accepts healthy volunteers Results available

Low vs. Moderate to High Dose Vitamin D for Prevention of COVID-19

NCT04868903
Conditions
SARS-CoV-2 Infection
Interventions
Vitamin D3
Dietary Supplement
Lead sponsor
University of Chicago
Other
Eligibility
18 Years and older
Enrollment
1,475 participants
Healthy volunteers
Accepts healthy volunteers
Timeline
2020 – 2024
U.S. locations
2
States / cities
Chicago, Illinois
Not listed Phase 4 Interventional Accepts healthy volunteers

Effects of Omega-3 Fatty Acids on Bone and Frailty

NCT00634686
Conditions
Osteoporosis, Frailty
Interventions
DHA/EPA, Placebo capsule, Calcium with vitamin D
Dietary Supplement
Lead sponsor
Donaghue Medical Research Foundation
Other
Eligibility
65 Years and older · Female only
Enrollment
150 participants
Healthy volunteers
Accepts healthy volunteers
Timeline
2007 – 2009
U.S. locations
1
States / cities
Farmington, Connecticut
Conditions
Gastric Bypass, Parathyroid Hormone
Interventions
Paricalcitol, Cholecalciferol, Placebo
Drug
Lead sponsor
Kerstyn C. Zalesin, M.D.
Other
Eligibility
18 Years to 100 Years
Enrollment
49 participants
Healthy volunteers
Accepts healthy volunteers
Timeline
2010 – 2015
U.S. locations
1
States / cities
Royal Oak, Michigan
Completed Not applicable Interventional Results available

Individualized Response to Vitamin D Treatment Study

NCT02925195
Conditions
Characteristics That Modify the Response to Cholecalciferol Treatment
Interventions
Vitamin D3, Placebo
Dietary Supplement · Drug
Lead sponsor
University of Washington
Other
Eligibility
18 Years and older
Enrollment
666 participants
Healthy volunteers
Healthy volunteers not accepted
Timeline
2017 – 2022
U.S. locations
5
States / cities
Los Angeles, California • Evanston, Illinois • Baltimore, Maryland + 2 more
Conditions
Healthy
Interventions
Vitamin D3 1000 IU, Placebo Tablet
Dietary Supplement
Lead sponsor
University of Pittsburgh
Other
Eligibility
8 Years to 14 Years
Enrollment
157 participants
Healthy volunteers
Accepts healthy volunteers
Timeline
2008 – 2011
U.S. locations
1
States / cities
Pittsburgh, Pennsylvania
Completed Phase 3 Interventional Results available

Effect of Teriparatide on Hip Fracture Healing

NCT01473589
Conditions
Femur Neck Fracture
Interventions
Teriparatide, Placebo, Calcium supplementation, Vitamin D supplementation
Drug · Dietary Supplement
Lead sponsor
Eli Lilly and Company
Industry
Eligibility
50 Years and older
Enrollment
122 participants
Healthy volunteers
Healthy volunteers not accepted
Timeline
2012 – 2013
U.S. locations
24
States / cities
Phoenix, Arizona • Tucson, Arizona • La Mesa, California + 21 more
Conditions
Follicular Lymphoma, Small Lymphocytic Lymphoma, Marginal Zone Lymphoma, Mucosal-Associated Lymphoid Tissue Lymphoma
Interventions
Vitamin D, Rituximab, Placebo
Dietary Supplement · Biological · Other
Lead sponsor
Jonathan Friedberg
Other
Eligibility
18 Years and older
Enrollment
211 participants
Healthy volunteers
Healthy volunteers not accepted
Timeline
2017 – 2024
U.S. locations
7
States / cities
Miami, Florida • Atlanta, Georgia • Iowa City, Iowa + 4 more
Conditions
Bariatric Surgery Candidate
Interventions
AquaVanta Chewable Tablet, Flinstones Complete, Nature Made Calcium Softgels, Twin Labs Iron Caps, Rexall Vitamin B12 Tablet
Dietary Supplement
Lead sponsor
Yasoo Health
Industry
Eligibility
18 Years to 65 Years
Enrollment
61 participants
Healthy volunteers
Healthy volunteers not accepted
Timeline
2011 – 2014
U.S. locations
1
States / cities
Baltimore, Maryland
Conditions
Obesity and Overweight
Interventions
Postbiotic, Placebo
Dietary Supplement
Lead sponsor
ResBiotic Nutrition, Inc.
Industry
Eligibility
18 Years to 65 Years
Enrollment
80 participants
Healthy volunteers
Accepts healthy volunteers
Timeline
2025 – 2026
U.S. locations
1
States / cities
Birmingham, Alabama
Completed Early Phase 1 Interventional Accepts healthy volunteers Results available

CYP3A4 Activity and Mineral Homeostasis

NCT02019875
Conditions
Vitamin D and Calcium Homeostasis
Interventions
Rifampin, Clarithromycin, Grapefruit Juice, Placebo
Drug · Other
Lead sponsor
University of Washington
Other
Eligibility
18 Years to 60 Years
Enrollment
92 participants
Healthy volunteers
Accepts healthy volunteers
Timeline
2014 – 2020
U.S. locations
1
States / cities
Seattle, Washington