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Showing 1–24 of 436 matching trials from the live ClinicalTrials.gov search.
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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
Completed Not applicable Interventional Accepts healthy volunteers Results available

Vitamin D and Fish Oil for Autoimmune Disease, Inflammation and Knee Pain

NCT01351805
Conditions
Autoimmune Diseases, Systemic Inflammatory Process, Knee Pain Chronic, Osteoarthritis, Rheumatoid Arthritis
Interventions
Fish Oil, Vitamin D, placebo pill
Drug · Dietary Supplement · Other
Lead sponsor
Brigham and Women's Hospital
Other
Eligibility
50 Years and older
Enrollment
25,871 participants
Healthy volunteers
Accepts healthy volunteers
Timeline
2010 – 2025
U.S. locations
1
States / cities
Boston, Massachusetts
Conditions
Sarcopenia
Interventions
Placebo, HMB plus Vitamin D, Non-Exercise, Exercise
Dietary Supplement · Drug · Behavioral
Lead sponsor
Metabolic Technologies Inc.
Industry
Eligibility
60 Years and older
Enrollment
238 participants
Healthy volunteers
Accepts healthy volunteers
Timeline
2014 – 2019
U.S. locations
1
States / cities
Ames, Iowa
Completed Phase 3 Interventional Accepts healthy volunteers Results available

Combined Antioxidant and Preeclampsia Prediction Studies (CAPPS)

NCT00135707
Conditions
Preeclampsia
Interventions
Dietary Supplement/Vitamins, Placebo for Vitamin C and Vitamin E
Drug
Lead sponsor
The George Washington University Biostatistics Center
Other
Eligibility
Female only
Enrollment
10,154 participants
Healthy volunteers
Accepts healthy volunteers
Timeline
2003 – 2009
U.S. locations
16
States / cities
Birmingham, Alabama • Chicago, Illinois • Detroit, Michigan + 13 more
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
Active, not recruiting Phase 3 Interventional Accepts healthy volunteers Results available

Vitamin D and Omega-3 Trial (VITAL)

NCT01169259
Conditions
Cancer, Cardiovascular Disease
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
50 Years and older
Enrollment
25,871 participants
Healthy volunteers
Accepts healthy volunteers
Timeline
2010 – 2026
U.S. locations
1
States / cities
Boston, Massachusetts
Conditions
Muscle Power
Interventions
Vitamin D, Placebo
Dietary Supplement
Lead sponsor
Oklahoma State University
Other
Eligibility
18 Years to 35 Years
Enrollment
103 participants
Healthy volunteers
Accepts healthy volunteers
Timeline
2012 – 2013
U.S. locations
1
States / cities
Stillwater, Oklahoma
Completed Phase 1Phase 2 Interventional Accepts healthy volunteers

Changes in Breast Cancer Biomarkers Using Synergistic Prostaglandin Inhibitors

NCT01425476
Conditions
Breast Cancer
Interventions
Celecoxib, Placebo, Cholecalciferol
Drug
Lead sponsor
Hartford Hospital
Other
Eligibility
18 Years and older · Female only
Enrollment
45 participants
Healthy volunteers
Accepts healthy volunteers
Timeline
2008 – 2016
U.S. locations
1
States / cities
Grand Forks, North Dakota
Conditions
Stage, Colon Cancer, Stage I-III Colon Cancer, Stage IV Colon Cancer With Resectable Liver Metastases
Interventions
Vitamin D3, Placebo
Drug
Lead sponsor
Dana-Farber Cancer Institute
Other
Eligibility
18 Years and older
Enrollment
80 participants
Healthy volunteers
Healthy volunteers not accepted
Timeline
2014 – 2027
U.S. locations
1
States / cities
Boston, Massachusetts
Completed Phase 3 Interventional Accepts healthy volunteers Results available

Effects of Anorexia Nervosa on Peak Bone Mass

NCT01301183
Conditions
Anorexia Nervosa
Interventions
RhIGF-1 with transdermal 17-beta estradiol, Placebo and transdermal 17-beta estradiol
Drug
Lead sponsor
Massachusetts General Hospital
Other
Eligibility
14 Years to 22 Years · Female only
Enrollment
75 participants
Healthy volunteers
Accepts healthy volunteers
Timeline
2011 – 2020
U.S. locations
1
States / cities
Boston, Massachusetts
Completed Phase 2 Interventional Accepts healthy volunteers

Efficacy of Vitamin D in Colorectal Cancer Chemoprevention

NCT01574027
Conditions
Colorectal Cancer
Interventions
Vitamin D3 (cholecalciferol), Placebo
Drug
Lead sponsor
University of Illinois at Chicago
Other
Eligibility
50 Years and older
Enrollment
55 participants
Healthy volunteers
Accepts healthy volunteers
Timeline
2008 – 2011
U.S. locations
1
States / cities
Chicago, Illinois
Conditions
Vitamin D Deficiency, Rotator Cuff Tears
Interventions
Vitamin D3 supplementation, Placebo
Dietary Supplement · Other
Lead sponsor
Community Memorial Health System
Other
Eligibility
18 Years to 65 Years
Enrollment
240 participants
Healthy volunteers
Accepts healthy volunteers
Timeline
2021 – 2024
U.S. locations
2
States / cities
Ventura, California
Conditions
Chronic Kidney Disease
Interventions
cholecalciferol, doxercalciferol, placebo
Dietary Supplement
Lead sponsor
Indiana University
Other
Eligibility
18 Years and older
Enrollment
100 participants
Healthy volunteers
Healthy volunteers not accepted
Timeline
2008 – 2012
U.S. locations
1
States / cities
Indianapolis, Indiana
Conditions
Elderly, Frail
Interventions
Vitamin D + Sham Exercise, Vitamin D Placebo + Exercise, Vitamin D Placebo + Sham Exercise, Vitamin D + Exercise
Drug · Procedure
Lead sponsor
Pfizer
Industry
Eligibility
75 Years and older
Enrollment
64 participants
Healthy volunteers
Healthy volunteers not accepted
Timeline
2005 – 2008
U.S. locations
4
States / cities
Farmington, Connecticut • Hyattsville, Maryland • Roslindale, Massachusetts + 1 more
Conditions
COVID-19, Coronavirus Infection, Sars-CoV2, Corona Virus Infection, COVID, Coronavirus, Coronavirus-19, Coronavirus 19
Interventions
Hydroxychloroquine, Vitamin C, Vitamin D, Zinc
Drug · Dietary Supplement
Lead sponsor
ProgenaBiome
Other
Eligibility
18 Years and older
Enrollment
254 participants
Healthy volunteers
Accepts healthy volunteers
Timeline
2020 – 2024
U.S. locations
1
States / cities
Ventura, California
Conditions
Ovarian Cancer, Fallopian Tube Cancer, Primary Peritoneal Cancer
Interventions
Arm A: Vitamin D3 Group, Placebo
Dietary Supplement
Lead sponsor
Northwestern University
Other
Eligibility
18 Years and older · Female only
Enrollment
7 participants
Healthy volunteers
Healthy volunteers not accepted
Timeline
2012 – 2015
U.S. locations
2
States / cities
Chicago, Illinois • Evanston, Illinois
Conditions
Coronary Artery Disease, Chronic Kidney Disease, Hypovitaminosis D, Secondary Hyperparathyroidism
Interventions
paricalcitol, placebo
Drug
Lead sponsor
Thomas Jefferson University
Other
Eligibility
18 Years and older
Enrollment
10 participants
Healthy volunteers
Healthy volunteers not accepted
Timeline
2010 – 2011
U.S. locations
1
States / cities
Philadelphia, Pennsylvania
Completed Not applicable Interventional Accepts healthy volunteers

Rejuvant™ Safety and Biomarker Study

NCT04821401
Conditions
Aging Well
Interventions
Rejuvant, Placebo
Dietary Supplement
Lead sponsor
Ponce De Leon Health
Industry
Eligibility
45 Years to 75 Years
Enrollment
100 participants
Healthy volunteers
Accepts healthy volunteers
Timeline
2020 – 2022
U.S. locations
1
States / cities
Indianapolis, Indiana
Conditions
Chronic Obstructive Pulmonary Disease, Muscle Weakness
Interventions
Cholecalciferol, Laboratory Biomarker Analysis, Multivitamin, Placebo, Questionnaire Administration
Dietary Supplement · Other
Lead sponsor
Roswell Park Cancer Institute
Other
Eligibility
50 Years and older
Enrollment
4 participants
Healthy volunteers
Healthy volunteers not accepted
Timeline
2014 – 2017
U.S. locations
1
States / cities
Buffalo, New York
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 Phase 2 Interventional Accepts healthy volunteers Results available

Analysis of Response of Subjects With Atopic Dermatitis or Psoriasis to Oral Vitamin D3

NCT00789880
Conditions
Atopic Dermatitis, Psoriasis
Interventions
Vitamin D3, Placebo
Drug
Lead sponsor
National Institute of Allergy and Infectious Diseases (NIAID)
NIH
Eligibility
18 Years to 70 Years
Enrollment
82 participants
Healthy volunteers
Accepts healthy volunteers
Timeline
2008 – 2009
U.S. locations
3
States / cities
San Diego, California • Denver, Colorado • Portland, Oregon
Completed Phase 3 Interventional Accepts healthy volunteers Results available

Improving the Understanding of the Response to Vitamin D Supplementation

NCT01465178
Conditions
Vitamin D Deficiency
Interventions
cholecalciferol, Placebo
Dietary Supplement
Lead sponsor
University of Wisconsin, Madison
Other
Eligibility
50 Years to 100 Years · Female only
Enrollment
62 participants
Healthy volunteers
Accepts healthy volunteers
Timeline
2011 – 2014
U.S. locations
1
States / cities
Madison, Wisconsin
Completed Phase 1 Interventional Accepts healthy volunteers Results available

Vitamin D as a Therapeutic Adjunct in the Stimulant Treatment of ADHD

NCT03103750
Conditions
ADHD
Interventions
Magnetic Resonance Imaging (MRI), PHNO, calcitriol, Placebo oral capsule, high-resolution research tomography, Dextro Amphetamine
Procedure · Drug · Dietary Supplement
Lead sponsor
Yale University
Other
Eligibility
18 Years to 50 Years
Enrollment
24 participants
Healthy volunteers
Accepts healthy volunteers
Timeline
2017 – 2023
U.S. locations
1
States / cities
New Haven, Connecticut
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