Independent directory Public ClinicalTrials.gov records United States
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ClinicalTrials.gov public records Last synced Oct 15, 2026, 9:02 PM EDT

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Showing 625–648 of 960 matching trials from the live ClinicalTrials.gov search.
Conditions
Hypocalcemia, Thyroid Diseases
Interventions
Tums, Calcitriol
Dietary Supplement
Lead sponsor
Lahey Clinic
Other
Eligibility
18 Years and older
Enrollment
82 participants
Healthy volunteers
Accepts healthy volunteers
Timeline
2017 – 2019
U.S. locations
1
States / cities
Burlington, 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
Recruiting Not applicable Interventional Accepts healthy volunteers

Prunes Preventing Bone Loss in Perimenopause

NCT07120997
Conditions
Perimenopausal Bone Loss
Interventions
Prunes, Calcium supplement, Vitamin D Supplement
Dietary Supplement
Lead sponsor
Penn State University
Other
Eligibility
44 Years to 55 Years · Female only
Enrollment
124 participants
Healthy volunteers
Accepts healthy volunteers
Timeline
2025 – 2029
U.S. locations
1
States / cities
University Park, Pennsylvania
Conditions
Obesity, Insulin Resistance, Vitamin D Deficiency
Interventions
Vitamin D3
Drug
Lead sponsor
Perrin C White, MD
Other
Eligibility
6 Years to 17 Years
Enrollment
109 participants
Healthy volunteers
Healthy volunteers not accepted
Timeline
2011 – 2015
U.S. locations
1
States / cities
Dallas, Texas
Conditions
Hyperparathyroidism
Interventions
Vitamin D, Four-dimensional computed tomography (4DCT)
Drug · Device
Lead sponsor
M.D. Anderson Cancer Center
Other
Eligibility
21 Years and older
Enrollment
22 participants
Healthy volunteers
Healthy volunteers not accepted
Timeline
2007 – 2018
U.S. locations
1
States / cities
Houston, Texas
Completed Phase 1 Interventional Accepts healthy volunteers Results available

Blackcurrants Modify Gut Microbiota and Reduce Osteoporosis and CVD Risk

NCT04431960
Conditions
Postmenopausal Osteoporosis, Gut Microbiota, Cardiovascular Diseases
Interventions
blackcurrant (BC) extract
Drug
Lead sponsor
University of Connecticut
Other
Eligibility
45 Years to 60 Years · Female only
Enrollment
51 participants
Healthy volunteers
Accepts healthy volunteers
Timeline
2021 – 2022
U.S. locations
1
States / cities
Storrs, Connecticut
Completed Not applicable Interventional Accepts healthy volunteers

The Effects of a Multi-vitamin Supplement in Adult Females

NCT03828097
Conditions
Health, Subjective
Interventions
Experimental supplement, Placebo
Dietary Supplement
Lead sponsor
Auburn University
Other
Eligibility
21 Years to 40 Years · Female only
Enrollment
94 participants
Healthy volunteers
Accepts healthy volunteers
Timeline
2018 – 2019
U.S. locations
1
States / cities
Auburn, Alabama
Completed Not applicable Interventional Accepts healthy volunteers Results available

Comparing a Novel Phototherapy Kiosk to Oral Vitamin D Supplementation

NCT04556136
Conditions
Hypovitaminosis D
Interventions
Standing Phototherapy Kiosk, D3 Oral supplement
Device · Dietary Supplement
Lead sponsor
Madigan Army Medical Center
Federal
Eligibility
18 Years to 69 Years
Enrollment
106 participants
Healthy volunteers
Accepts healthy volunteers
Timeline
2018 – 2019
U.S. locations
1
States / cities
Tacoma, Washington
Completed Not applicable Interventional Results available

Vitamin D in Minorities With Prediabetes

NCT00876928
Conditions
Pre-diabetes
Interventions
vitamin D, placebo
Drug
Lead sponsor
Charles Drew University of Medicine and Science
Other
Eligibility
18 Years to 90 Years
Enrollment
117 participants
Healthy volunteers
Healthy volunteers not accepted
Timeline
2009 – 2012
U.S. locations
1
States / cities
Los Angeles, California
Conditions
Vitamin D Deficiency, End Stage Renal Disease
Interventions
Not listed
Lead sponsor
Winthrop University Hospital
Other
Eligibility
18 Years to 85 Years
Enrollment
50 participants
Healthy volunteers
Healthy volunteers not accepted
Timeline
2011 – 2012
U.S. locations
2
States / cities
Mineola, New York
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
Conditions
Chronic Kidney Disease, Secondary Hyperparathyroidism, Chronic Renal Insufficiency, Chronic Renal Failure
Interventions
CTA018 Injection
Drug
Lead sponsor
OPKO IP Holdings II, Inc.
Industry
Eligibility
18 Years to 80 Years
Enrollment
41 participants
Healthy volunteers
Healthy volunteers not accepted
Timeline
2008 – 2010
U.S. locations
5
States / cities
Pembroke Pines, Florida • Meridian, Idaho • Springfield, Massachusetts + 2 more
Completed Not applicable Interventional Accepts healthy volunteers

Vitamin D2, Muscle Damage, NASCAR Pitcrew

NCT01825616
Conditions
Muscle Function, Muscle Soreness, Vitamin D Status
Interventions
Vitamin D2 mushroom powder, Placebo
Dietary Supplement · Other
Lead sponsor
Appalachian State University
Other
Eligibility
20 Years to 40 Years · Male only
Enrollment
33 participants
Healthy volunteers
Accepts healthy volunteers
Timeline
2012 – 2013
U.S. locations
3
States / cities
Kannapolis, North Carolina
Conditions
Chronic Kidney Disease
Interventions
D6-25-hydroxyvitamin D3
Drug
Lead sponsor
University of Washington
Other
Eligibility
18 Years and older
Enrollment
19 participants
Healthy volunteers
Healthy volunteers not accepted
Timeline
2018 – 2021
U.S. locations
1
States / cities
Seattle, Washington
Conditions
Hepatitis C
Interventions
Telaprevir, Peginterferon alfa-2a, Ribavirin, Vitamin D
Drug · Dietary Supplement
Lead sponsor
Timothy Morgan, MD
Other
Eligibility
18 Years and older
Healthy volunteers
Healthy volunteers not accepted
Timeline
Started 2013
U.S. locations
4
States / cities
Long Beach, California • Minneapolis, Minnesota • Kansas City, Missouri + 1 more
Conditions
HIV
Interventions
Tenofovir/emtricitabine, Tenofovir/emtricitabine/efavirenz, Raltegravir
Drug
Lead sponsor
Indiana University
Other
Eligibility
18 Years and older
Enrollment
30 participants
Healthy volunteers
Healthy volunteers not accepted
Timeline
2011 – 2013
U.S. locations
1
States / cities
Indianapolis, Indiana
Recruiting Not applicable Interventional Accepts healthy volunteers

Evaluating Response to Vitamin D3 and K2 Supplementation in Healthcare Personnel

NCT07199829
Conditions
Hypovitaminosis D, Hypovitaminosis
Interventions
Vitamin Arm 1, Vitamin Arm 2, Vitamin Arm 3, Placebo
Dietary Supplement · Other
Lead sponsor
Madigan Army Medical Center
Federal
Eligibility
18 Years to 69 Years
Enrollment
96 participants
Healthy volunteers
Accepts healthy volunteers
Timeline
2025 – 2026
U.S. locations
1
States / cities
Tacoma, Washington
Conditions
Bone Loss, Periodontitis
Interventions
Periodontal surgery, FORTEO, Placebo, Vitamin D and Calcium
Procedure · Drug · Dietary Supplement
Lead sponsor
University of Michigan
Other
Eligibility
30 Years to 75 Years
Enrollment
40 participants
Healthy volunteers
Healthy volunteers not accepted
Timeline
2004 – 2009
U.S. locations
1
States / cities
Ann Arbor, Michigan
Completed Phase 4 Interventional Accepts healthy volunteers Results available

Effect of Vitamin D Supplementation on Muscle Mass and Function

NCT01199926
Conditions
Obesity, Insulin Resistance, Inflammation
Interventions
Vitamin D, Placebo
Dietary Supplement · Drug
Lead sponsor
Purdue University
Other
Eligibility
18 Years to 35 Years
Enrollment
34 participants
Healthy volunteers
Accepts healthy volunteers
Timeline
2008 – 2010
U.S. locations
1
States / cities
West Lafayette, Indiana
Completed Not applicable Interventional Accepts healthy volunteers Results available

Tumor Necrosis Factor Decreases Vitamin D Dependant Calcium Absorption

NCT00427804
Conditions
Rheumatoid Arthritis, Crohn's Disease
Interventions
calcitriol
Drug
Lead sponsor
Atlanta VA Medical Center
Federal
Eligibility
18 Years to 50 Years · Male only
Enrollment
9 participants
Healthy volunteers
Accepts healthy volunteers
Timeline
2007 – 2009
U.S. locations
1
States / cities
Atlanta, Georgia
Completed Phase 3 Interventional Accepts healthy volunteers Results available

Study of Vitamin D and Omega-3 Supplementation for Preventing Diabetes

NCT01633177
Conditions
Type 2 Diabetes
Interventions
Vitamin D3, Omega-3 fatty acid (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
22,220 participants
Healthy volunteers
Accepts healthy volunteers
Timeline
2011 – 2024
U.S. locations
1
States / cities
Boston, Massachusetts
Conditions
Prostate Cancer
Interventions
calcitriol, dexamethasone
Dietary Supplement · Drug
Lead sponsor
Roswell Park Cancer Institute
Other
Eligibility
18 Years and older · Male only
Enrollment
15 participants
Healthy volunteers
Healthy volunteers not accepted
Timeline
2002 – 2006
U.S. locations
2
States / cities
Buffalo, New York • Pittsburgh, Pennsylvania
Completed Phase 2 Interventional Results available

Vitamin D Dose Finding Study

NCT01092338
Conditions
HIV Infections, AIDS
Interventions
Cholecalciferol (Vit D3)
Drug
Lead sponsor
Children's Hospital of Philadelphia
Other
Eligibility
5 Years to 24 Years
Enrollment
44 participants
Healthy volunteers
Healthy volunteers not accepted
Timeline
2010 – 2011
U.S. locations
1
States / cities
Philadelphia, Pennsylvania
Completed Phase 2Phase 3 Interventional Accepts healthy volunteers Results available

"Clinical Trial to Determine the Efficacy of Vitamin D for Acne Therapy"

NCT01694433
Conditions
Acne Vulgaris
Interventions
Calcipotriene, Placebo
Drug
Lead sponsor
University of California, Los Angeles
Other
Eligibility
18 Years and older
Enrollment
66 participants
Healthy volunteers
Accepts healthy volunteers
Timeline
2013 – 2014
U.S. locations
1
States / cities
Los Angeles, California