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Showing 505–528 of 550 matching trials from the live ClinicalTrials.gov search.
Conditions
Quality of Life, Body Mass Index
Interventions
MannaBears, AlgaeCal Calcium, Calcium carbonate, Vitamin D3
Dietary Supplement
Lead sponsor
Integrative Health Technologies, Inc.
Network
Eligibility
5 Years to 19 Years
Enrollment
200 participants
Healthy volunteers
Accepts healthy volunteers
Timeline
2013 – 2014
U.S. locations
1
States / cities
San Antonio, Texas
Conditions
Diabetic Nephropathies
Interventions
Calcitriol, Losartan
Dietary Supplement · Drug
Lead sponsor
Weill Cornell Medical College in Qatar
Other
Eligibility
21 Years to 80 Years
Enrollment
56 participants
Healthy volunteers
Healthy volunteers not accepted
Timeline
2014 – 2015
U.S. locations
1
States / cities
New York, New York
Completed Not applicable Interventional Results available

Vitamin D Supplements for HIV-positive Patients on cART

NCT01295034
Conditions
HIV-associated Co-morbidities
Interventions
conventional vitamin D treatment, tiered/titrated vitamin D dosing
Dietary Supplement · Drug
Lead sponsor
Andrea Branch
Other
Eligibility
18 Years to 70 Years
Enrollment
62 participants
Healthy volunteers
Healthy volunteers not accepted
Timeline
2011 – 2015
U.S. locations
1
States / cities
New York, New York
Completed Phase 1Phase 2 Interventional Accepts healthy volunteers Results available

Human Lung Responses to Respiratory Pathogens

NCT01967628
Conditions
Respiratory Infection
Interventions
Vitamin D3 (cholecalciferol), Placebo Sugar Pill
Dietary Supplement
Lead sponsor
University of Iowa
Other
Eligibility
18 Years to 60 Years
Enrollment
98 participants
Healthy volunteers
Accepts healthy volunteers
Timeline
2007 – 2010
U.S. locations
1
States / cities
Iowa City, Iowa
Conditions
Vitamin D Deficiency
Interventions
Treatment
Drug
Lead sponsor
Johns Hopkins All Children's Hospital
Other
Eligibility
36 Months to 18 Years
Enrollment
26 participants
Healthy volunteers
Accepts healthy volunteers
Timeline
2016 – 2019
U.S. locations
1
States / cities
St. Petersburg, Florida
Conditions
Hypovitaminosis D
Interventions
100,000 IU cholecalciferol, Placebo
Drug
Lead sponsor
Massachusetts General Hospital
Other
Eligibility
18 Years and older
Enrollment
60 participants
Healthy volunteers
Healthy volunteers not accepted
Timeline
2013 – 2015
U.S. locations
1
States / cities
Boston, Massachusetts
Completed Not applicable Interventional Accepts healthy volunteers

Vitamin D3 Supplementation Pilot Study

NCT01546103
Conditions
Vitamin D Deficiency
Interventions
Cholecalciferol
Dietary Supplement
Lead sponsor
Children's Hospital of Philadelphia
Other
Eligibility
12 Years to 17 Years
Enrollment
39 participants
Healthy volunteers
Accepts healthy volunteers
Timeline
2011 – 2012
U.S. locations
1
States / cities
Philadelphia, Pennsylvania
Completed Not applicable Interventional Results available

Vitamin D and Type 2 Diabetes Study

NCT01942694
Conditions
Prediabetes, Type 2 Diabetes
Interventions
Vitamin D (Cholecalciferol), Placebo
Dietary Supplement · Other
Lead sponsor
Tufts Medical Center
Other
Eligibility
30 Years and older
Enrollment
2,423 participants
Healthy volunteers
Healthy volunteers not accepted
Timeline
2013 – 2018
U.S. locations
25
States / cities
Phoenix, Arizona • Los Angeles, California • Palo Alto, California + 20 more
Completed Not applicable Interventional Accepts healthy volunteers

Clinical Study on the Bioequivalence of Vitamin D in Healthy Adults

NCT03552666
Conditions
Bioequivalence of Vitamin D in Healthy Adults
Interventions
vitamin D3
Dietary Supplement
Lead sponsor
Church & Dwight Company, Inc.
Industry
Eligibility
18 Years to 45 Years
Enrollment
9 participants
Healthy volunteers
Accepts healthy volunteers
Timeline
2016 – 2017
U.S. locations
1
States / cities
Princeton, New Jersey
Completed Phase 1 Interventional Accepts healthy volunteers

Effect of Vitamin D and Calcium on Genes in the Colon

NCT00298545
Conditions
Colorectal Polyps, Colorectal Adenoma, Adenocarcinoma
Interventions
placebo and Calcitriol, Calcium and Calcitriol
Drug
Lead sponsor
Rockefeller University
Other
Eligibility
48 Years to 72 Years
Enrollment
10 participants
Healthy volunteers
Accepts healthy volunteers
Timeline
2005 – 2009
U.S. locations
1
States / cities
New York, New York
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
Terminated Not applicable Interventional Accepts healthy volunteers

Vitamin D Supplementation and Metabolism in Vitamin D Deficient Elderly

NCT01145703
Conditions
Vitamin D Deficiency, Metabolic Syndrome
Interventions
RDA Vitamin D3 only, Vitamin D2/3 Repletion only, Vitamin D2/3 Repletion + AEX, Vitamin D2/3 Repletion + RT
Dietary Supplement · Other
Lead sponsor
Baltimore VA Medical Center
Federal
Eligibility
40 Years to 85 Years
Enrollment
39 participants
Healthy volunteers
Accepts healthy volunteers
Timeline
2010 – 2013
U.S. locations
1
States / cities
Baltimore, Maryland
Conditions
Secondary Hyperparathyroidism, Chronic Kidney Disease
Interventions
Paricalcitol, Calcitriol
Drug
Lead sponsor
Washington University School of Medicine
Other
Eligibility
18 Years and older
Enrollment
110 participants
Healthy volunteers
Healthy volunteers not accepted
Timeline
2009 – 2013
U.S. locations
4
States / cities
Chicago, Illinois • Evanston, Illinois • Detroit, Michigan + 1 more
Conditions
Vitamin D Deficiency, Secondary Hyperparathyroidism, Obesity
Interventions
Ergocalciferol, Cholecalciferol
Drug
Lead sponsor
Weill Medical College of Cornell University
Other
Eligibility
18 Years to 65 Years
Enrollment
60 participants
Healthy volunteers
Accepts healthy volunteers
Timeline
2006 – 2007
U.S. locations
1
States / cities
New York, New York
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
HIV Infections
Interventions
Vitamin D supplement, Placebo
Dietary Supplement · Other
Lead sponsor
University of North Carolina, Chapel Hill
Other
Eligibility
18 Years to 24 Years
Enrollment
207 participants
Healthy volunteers
Healthy volunteers not accepted
Timeline
2007 – 2010
U.S. locations
14
States / cities
Los Angeles, California • San Francisco, California • Washington D.C., District of Columbia + 10 more
Conditions
Vitamin D Deficiency, Preterm Infants, Bronchopulmonary Dysplasia
Interventions
Cholecalciferol, Placebo
Dietary Supplement
Lead sponsor
University of Alabama at Birmingham
Other
Eligibility
1 Minute to 7 Days
Enrollment
100 participants
Healthy volunteers
Healthy volunteers not accepted
Timeline
2012 – 2016
U.S. locations
1
States / cities
Birmingham, Alabama
Active, not recruiting Not applicable Interventional Accepts healthy volunteers Results available

LungVITamin D and OmegA-3 Trial (lungVITAL)

NCT01728571
Conditions
COPD, Asthma, Pulmonary Function, Pneumonia
Interventions
Vitamin D3, fish oil, Vitamin D3 placebo, Fish oil placebo
Dietary Supplement
Lead sponsor
Brigham and Women's Hospital
Other
Eligibility
50 Years and older
Enrollment
25,871 participants
Healthy volunteers
Accepts healthy volunteers
Timeline
2010 – 2027
U.S. locations
1
States / cities
Boston, Massachusetts
Conditions
Osteoporosis
Interventions
Small Particle Size Calcium Carbonate Supplement, Large Particle Size Calcium Carbonate Supplement, Vitamin D, Calcium Placebo
Dietary Supplement
Lead sponsor
Purdue University
Other
Eligibility
12 Years to 14 Years · Female only
Enrollment
55 participants
Healthy volunteers
Accepts healthy volunteers
Timeline
2007
U.S. locations
1
States / cities
West Lafayette, Indiana
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
Completed Not applicable Interventional Accepts healthy volunteers

Vitamin D Status and Dose Response in Infants

NCT01042561
Conditions
Vitamin D, Prematurity
Interventions
Vitamin D3, vitamin D3 placebo
Dietary Supplement
Lead sponsor
University of Nebraska
Other
Eligibility
5 Minutes to 3 Months
Enrollment
64 participants
Healthy volunteers
Accepts healthy volunteers
Timeline
2009 – 2010
U.S. locations
1
States / cities
Omaha, Nebraska
Completed Not applicable Interventional Accepts healthy volunteers

DAYLIGHT: Vitamin D Therapy in Individuals at High Risk of Hypertension

NCT01240512
Conditions
Hypertension, Vitamin D Deficiency, Pre-Hypertension
Interventions
Cholecalciferol
Drug
Lead sponsor
Massachusetts General Hospital
Other
Eligibility
18 Years to 50 Years
Enrollment
534 participants
Healthy volunteers
Accepts healthy volunteers
Timeline
2010 – 2013
U.S. locations
3
States / cities
Hartford, Connecticut • Boston, Massachusetts • Minneapolis, Minnesota
Completed Not applicable Interventional Accepts healthy volunteers Results available

Impact of Vitamin D Supplementation on Lactation Associated Bone Loss

NCT00903344
Conditions
Osteoporosis
Interventions
Vitamin D3, Multivitamin
Drug · Dietary Supplement
Lead sponsor
Leigh Eck, MD
Other
Eligibility
18 Years and older · Female only
Enrollment
22 participants
Healthy volunteers
Accepts healthy volunteers
Timeline
2009 – 2012
U.S. locations
1
States / cities
Kansas City, Missouri
Conditions
Gestational Hypertension, Toxemia, Superimposed Preeclampsia, Eclampsia, HELLP Syndrome
Interventions
Vitamin D3
Drug
Lead sponsor
Stony Brook University
Other
Eligibility
18 Years and older · Female only
Enrollment
412 participants
Healthy volunteers
Accepts healthy volunteers
Timeline
2016 – 2019
U.S. locations
1
States / cities
Stony Brook, New York