Independent directory Public ClinicalTrials.gov records United States
Clear filters

These results were retrieved from the live ClinicalTrials.gov registry. Filters and sort order apply to this result list.

ClinicalTrials.gov public records Last synced Oct 14, 2026, 8:32 PM EDT

Data is sourced from official ClinicalTrials.gov public API records. Always review the official ClinicalTrials.gov record for the latest information.

Showing 289–312 of 437 matching trials from the live ClinicalTrials.gov search.
Conditions
Maternal Stress
Interventions
Vitamin D (Cholecalciferol ), Placebo
Dietary Supplement · Other
Lead sponsor
University of Idaho
Other
Eligibility
18 Years to 64 Years · Female only
Enrollment
80 participants
Healthy volunteers
Accepts healthy volunteers
Timeline
2024 – 2027
U.S. locations
2
States / cities
Coeur d'Alene, Idaho • Moscow, Idaho
Conditions
Breast Neoplasms
Interventions
Vitamin D, Calcium carbonate, Vitamin D, Placebo
Dietary Supplement · Drug · Other
Lead sponsor
Washington University School of Medicine
Other
Eligibility
18 Years and older · Female only
Enrollment
63 participants
Healthy volunteers
Healthy volunteers not accepted
Timeline
2005 – 2009
U.S. locations
1
States / cities
St Louis, Missouri
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
Human Immunodeficiency Virus (HIV), Vitamin D Deficiency, HIV Infections
Interventions
Vitamin D, Placebo
Drug · Other
Lead sponsor
University Hospitals Cleveland Medical Center
Other
Eligibility
18 Years and older
Enrollment
45 participants
Healthy volunteers
Healthy volunteers not accepted
Timeline
2010
U.S. locations
1
States / cities
Cleveland, Ohio
Conditions
Obesity
Interventions
Drisdol (Ergocalciferol) Vitamin D2, Placebo
Drug
Lead sponsor
Stanford University
Other
Eligibility
11 Years to 17 Years
Enrollment
40 participants
Healthy volunteers
Healthy volunteers not accepted
Timeline
2010 – 2012
U.S. locations
1
States / cities
Stanford, California
Conditions
Healthy
Interventions
Vitamin D, Placebo
Dietary Supplement
Lead sponsor
University of Kentucky
Other
Eligibility
18 Years and older
Enrollment
45 participants
Healthy volunteers
Accepts healthy volunteers
Timeline
2011 – 2012
U.S. locations
1
States / cities
Lexington, Kentucky
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
Conditions
Secondary Hyperparathyroidism, Renal Failure, Chronic Renal Insufficiency
Interventions
Hectorol (doxercalciferol capsules), 0.5mcg
Drug
Lead sponsor
Genzyme, a Sanofi Company
Industry
Eligibility
18 Years and older
Enrollment
70 participants
Healthy volunteers
Healthy volunteers not accepted
Timeline
2005 – 2007
U.S. locations
17
States / cities
Phoenix, Arizona • Alhambra, California • Riverside, California + 14 more
Completed Not applicable Interventional Accepts healthy volunteers

Vitamin D Needs of Early Adolescent Children

NCT00931580
Conditions
Healthy
Interventions
Vitamin D3
Dietary Supplement
Lead sponsor
University of Georgia
Other
Eligibility
9 Years to 13 Years
Enrollment
323 participants
Healthy volunteers
Accepts healthy volunteers
Timeline
2009 – 2011
U.S. locations
3
States / cities
Athens, Georgia • Indianapolis, Indiana • West Lafayette, Indiana
Conditions
Leukemia, Lymphoblastic, Acute, Osteoporosis
Interventions
Calcium carbonate (Tums), vitamin D, Placebo
Drug · Other
Lead sponsor
St. Jude Children's Research Hospital
Other
Eligibility
Not listed
Enrollment
429 participants
Healthy volunteers
Healthy volunteers not accepted
Timeline
2000 – 2011
U.S. locations
3
States / cities
Memphis, Tennessee
Completed Phase 2Phase 3 Interventional Results available

Hypovitaminosis D in Neurocritical Patients

NCT02881957
Conditions
Craniocerebral Trauma, Intracranial Aneurysm, Brain Neoplasms, Spinal Cord Injuries, Seizures, Meningitis, Stroke, Intracranial Hemorrhages, Critical Illness, Vitamin d Deficiency
Interventions
Cholecalciferol, Placebo
Drug · Other
Lead sponsor
University of Utah
Other
Eligibility
18 Years and older
Enrollment
274 participants
Healthy volunteers
Healthy volunteers not accepted
Timeline
2016 – 2018
U.S. locations
1
States / cities
Salt Lake City, Utah
Completed Phase 1 Interventional Accepts healthy volunteers Results available

Healthy Combine Study

NCT03136705
Conditions
Healthy
Interventions
Nicotinamide, Lanthanum Carbonate, Lanthanum Carbonate Placebo, Nicotinamide Placebo
Drug
Lead sponsor
Northwestern University
Other
Eligibility
18 Years to 60 Years
Enrollment
39 participants
Healthy volunteers
Accepts healthy volunteers
Timeline
2016 – 2017
U.S. locations
1
States / cities
Chicago, Illinois
Conditions
Deficiency of Vitamin D3, COPD
Interventions
Cholecalciferol, multivitamin, Placebo
Dietary Supplement
Lead sponsor
University of Pittsburgh
Other
Eligibility
50 Years to 85 Years
Enrollment
10 participants
Healthy volunteers
Healthy volunteers not accepted
Timeline
2016 – 2018
U.S. locations
1
States / cities
Pittsburgh, Pennsylvania
Conditions
Immunotherapy, Cutaneous Squamous Cell Carcinoma, Actinic Keratoses, Organ Transplant Recipients, Skin Cancer
Interventions
Calcipotriol Only Product in Cutaneous Dose Form, Vaseline, Topical 5FU
Drug
Lead sponsor
Massachusetts General Hospital
Other
Eligibility
50 Years and older
Healthy volunteers
Accepts healthy volunteers
Timeline
2026 – 2030
U.S. locations
2
States / cities
Boston, Massachusetts • St Louis, Missouri
Completed Phase 2 Interventional Results available

Males, Antioxidants, and Infertility Trial

NCT02421887
Conditions
Male Infertility
Interventions
Antioxidant Supplement, Placebo
Drug · Other
Lead sponsor
Yale University
Other
Eligibility
18 Years and older · Male only
Enrollment
171 participants
Healthy volunteers
Healthy volunteers not accepted
Timeline
2015 – 2018
U.S. locations
10
States / cities
Los Angeles, California • San Francisco, California • Sunnyvale, California + 7 more
Conditions
Osteoporosis
Interventions
Alendronate
Drug
Lead sponsor
Medical University of South Carolina
Other
Eligibility
5 Years to 15 Years
Enrollment
22 participants
Healthy volunteers
Healthy volunteers not accepted
Timeline
2003 – 2009
U.S. locations
1
States / cities
Charleston, South Carolina
Conditions
Polycystic Ovary Syndrome
Interventions
Vitamin D, Placebo
Dietary Supplement · Drug
Lead sponsor
Milton S. Hershey Medical Center
Other
Eligibility
18 Years to 45 Years · Female only
Enrollment
36 participants
Healthy volunteers
Healthy volunteers not accepted
Timeline
2009 – 2014
U.S. locations
1
States / cities
Hershey, Pennsylvania
Completed Phase 2 Interventional Results available

Effects of Vitamin D in Parkinson's Disease (PD)

NCT01119131
Conditions
Parkinson Disease, Accidental Falls
Interventions
Vitamin D3, calcium, Placebo
Drug · Dietary Supplement · Other
Lead sponsor
VA Office of Research and Development
Federal
Eligibility
50 Years to 99 Years
Enrollment
101 participants
Healthy volunteers
Healthy volunteers not accepted
Timeline
2011 – 2015
U.S. locations
1
States / cities
Portland, Oregon
Conditions
Postpartum Depression, Preterm Labor
Interventions
Mindfulness-based intervention (with a focus on self-compassion; MBSC), Vitamin D
Behavioral · Dietary Supplement
Lead sponsor
University of Idaho
Other
Eligibility
18 Years to 50 Years · Female only
Enrollment
500 participants
Healthy volunteers
Healthy volunteers not accepted
Timeline
2021 – 2027
U.S. locations
1
States / cities
Coeur d'Alene, Idaho
Completed Not applicable Interventional Accepts healthy volunteers

Efficacy and Safety Safety of Nutritears® in Adults With Dry Eye Syndrome

NCT05481450
Conditions
Dry Eye, Dry Eye Syndromes
Interventions
Blink NutriTears, Placebo
Dietary Supplement
Lead sponsor
Applied Science & Performance Institute
Industry
Eligibility
18 Years to 65 Years
Enrollment
131 participants
Healthy volunteers
Accepts healthy volunteers
Timeline
2022 – 2023
U.S. locations
3
States / cities
Lutz, Florida • Tampa, Florida
Completed Phase 4 Interventional Results available

Evaluating Vitamin D3 Supplement on Post-Op Outcomes

NCT04177758
Conditions
Knee Osteoarthritis
Interventions
Vitamin D, Control
Drug
Lead sponsor
Rush University Medical Center
Other
Eligibility
18 Years to 80 Years
Enrollment
137 participants
Healthy volunteers
Healthy volunteers not accepted
Timeline
2020 – 2022
U.S. locations
1
States / cities
Chicago, Illinois
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
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
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