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Showing 1–24 of 203 matching trials from the live ClinicalTrials.gov search.
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Conditions
Adequate Vitamin C Status, Inadequate Vitamin C Status
Interventions
Vitamin C Supplement + Low Vitamin C Diet, Placebo + Low Vitamin C Diet
Dietary Supplement
Lead sponsor
Ohio State University
Other
Eligibility
18 Years to 50 Years
Enrollment
34 participants
Healthy volunteers
Healthy volunteers not accepted
Timeline
2025 – 2028
U.S. locations
1
States / cities
Columbus, Ohio
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
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
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
Completed Phase 1 Interventional Accepts healthy volunteers

The Effect of a Meal on Vitamin D Absorption

NCT01268176
Conditions
Vitamin D Deficiency
Interventions
cholecalciferol
Dietary Supplement
Lead sponsor
Tufts University
Other
Eligibility
50 Years to 69 Years
Enrollment
62 participants
Healthy volunteers
Accepts healthy volunteers
Timeline
2010 – 2012
U.S. locations
1
States / cities
Boston, Massachusetts
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
Not listed Phase 2 Interventional Accepts healthy volunteers

Cyclic Versus Daily Teriparatide on Bone Mass

NCT00668941
Conditions
Osteoporosis
Interventions
Teriparatide, Alendronate, Calcium, Vitamin D3
Drug · Dietary Supplement
Lead sponsor
Helen Hayes Hospital
Other
Eligibility
45 Years to 85 Years · Female only
Enrollment
140 participants
Healthy volunteers
Accepts healthy volunteers
Timeline
2005 – 2017
U.S. locations
1
States / cities
West Haverstraw, New York
Conditions
Postmenopausal Osteoporosis
Interventions
Strength/Weight Training & Drug/Supplement, Drug/Supplement only
Other · Combination Product
Lead sponsor
University of Nebraska
Other
Eligibility
35 Years to 75 Years · Female only
Enrollment
249 participants
Healthy volunteers
Healthy volunteers not accepted
Timeline
2002 – 2007
U.S. locations
4
States / cities
Kearney, Nebraska • Lincoln, Nebraska • Omaha, Nebraska + 1 more
Conditions
Center-involved Diabetic Macular Edema (CI-DME)
Interventions
Diabetes Visual Function Study (DiVFuSS) softgels, canola oil placebo softgels, 2 per day
Dietary Supplement · Other
Lead sponsor
ZeaVision, LLC
Industry
Eligibility
18 Years to 80 Years
Enrollment
150 participants
Healthy volunteers
Healthy volunteers not accepted
Timeline
2019 – 2021
U.S. locations
2
States / cities
Olympia, Washington • Tacoma, Washington
Conditions
Atrophy
Interventions
CaHMB (Dietary supplement, not Drug), CaLa
Drug · Dietary Supplement
Lead sponsor
University of Kansas Medical Center
Other
Eligibility
18 Years to 45 Years · Female only
Enrollment
30 participants
Healthy volunteers
Healthy volunteers not accepted
Timeline
2023 – 2029
U.S. locations
1
States / cities
Overland Park, Kansas
Conditions
Increase in Blood Levels of Nicotinamide Adenine Dinucleotide (NAD+)
Interventions
Oral supplement A, Oral supplement B, Oral supplement C, Oral supplement D, Oral Supplement D in combination with oral supplement C
Dietary Supplement
Lead sponsor
Supplement Formulators, Inc.
Industry
Eligibility
30 Years to 80 Years
Enrollment
8 participants
Healthy volunteers
Accepts healthy volunteers
Timeline
2018
U.S. locations
1
States / cities
Fort Lauderdale, Florida
Conditions
Obesity, Pediatric, Obesity, Childhood, Obesity, Morbid, Vitamin D Deficiency
Interventions
Vitamin D3
Dietary Supplement
Lead sponsor
Columbia University
Other
Eligibility
5 Years to 11 Years
Enrollment
6 participants
Healthy volunteers
Healthy volunteers not accepted
Timeline
2016 – 2019
U.S. locations
1
States / cities
New York, 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 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

Impact of Vitamin D on 25-hydroxyvitamin D Levels and Physical Function

NCT02293187
Conditions
Vitamin D Deficiency, Sarcopenia
Interventions
vitamin D3, Placebo
Dietary Supplement · Other
Lead sponsor
Tufts University
Other
Eligibility
60 Years to 85 Years
Enrollment
100 participants
Healthy volunteers
Accepts healthy volunteers
Timeline
2015 – 2018
U.S. locations
1
States / cities
Boston, Massachusetts
Terminated Not applicable Interventional Accepts healthy volunteers Results available

Study To Understand Fall Reduction and Vitamin D in You

NCT02166333
Conditions
Vitamin D Deficiency, Falls
Interventions
200 IU/d cholecalciferol, 1000 IU/d cholecalciferol, 2000 IU/d cholecalciferol, 4000 IU/d cholecalciferol
Dietary Supplement
Lead sponsor
Johns Hopkins University
Other
Eligibility
70 Years and older
Enrollment
688 participants
Healthy volunteers
Accepts healthy volunteers
Timeline
2015 – 2019
U.S. locations
2
States / cities
Baltimore, Maryland • Hagerstown, Maryland
Completed Phase 1Phase 2 Interventional Accepts healthy volunteers Results available

Impact of Smoking Cessation and γ-Tocopherol to Restore Vascular Endothelial Function

NCT01314443
Conditions
Endothelial Dysfunction
Interventions
Nicotine Replacement Therapy (NRT), Gamma-Tocopherol, Placebo, Smoking cessation
Other · Dietary Supplement · Behavioral
Lead sponsor
University of Connecticut
Other
Eligibility
18 Years to 60 Years
Enrollment
67 participants
Healthy volunteers
Accepts healthy volunteers
Timeline
2011 – 2014
U.S. locations
1
States / cities
Storrs, Connecticut
Active, not recruiting Phase 4 Interventional

Romosozumab Use to Build Skeletal Integrity

NCT05058976
Conditions
Osteoporosis, Osteoporosis, Postmenopausal, Osteoporosis Fracture
Interventions
Romosozumab, Placebo, Zoledronic acid, Calcium and Vitamin D
Drug · Dietary Supplement
Lead sponsor
Susan L. Greenspan
Other
Eligibility
65 Years and older · Female only
Enrollment
184 participants
Healthy volunteers
Healthy volunteers not accepted
Timeline
2021 – 2027
U.S. locations
1
States / cities
Pittsburgh, Pennsylvania
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
Terminated Phase 2 Interventional Results available

High Dose Vitamin D vs Standard Dose Vitamin D Study

NCT01988090
Conditions
Breast Cancer
Interventions
800 IU Vitamin D Supplement, 50,000 IU Vitamin D supplement
Drug
Lead sponsor
Mothaffar Rimawi
Other
Eligibility
18 Years and older · Female only
Enrollment
93 participants
Healthy volunteers
Healthy volunteers not accepted
Timeline
2013 – 2018
U.S. locations
2
States / cities
St Louis, Missouri • Houston, Texas
Conditions
Cancer of Pancreas
Interventions
Nutrawell Powder, Diet Only, OmegaRich fish oil supplement
Dietary Supplement · Other
Lead sponsor
Jonsson Comprehensive Cancer Center
Other
Eligibility
18 Years to 75 Years · Male only
Enrollment
2 participants
Healthy volunteers
Healthy volunteers not accepted
Timeline
2016 – 2021
U.S. locations
1
States / cities
Los Angeles, California
Conditions
Non-Cystic Acne
Interventions
VitaMedica® Clear Skin Formula capsules, Placebo Capsules
Dietary Supplement · Other
Lead sponsor
Ablon Skin Institute Research Center
Other
Eligibility
18 Years to 40 Years
Enrollment
40 participants
Healthy volunteers
Accepts healthy volunteers
Timeline
2023 – 2024
U.S. locations
1
States / cities
Manhattan Beach, California
Completed Not applicable Interventional Accepts healthy volunteers

Calcium Supplementation for a Healthy Weight (CaSHeW)

NCT01363115
Conditions
Obesity, Overweight
Interventions
Orange Juice fortified with Calcium and Vitamin D, Orange juice without Ca or VitD, Nutritional Counseling
Dietary Supplement · Behavioral
Lead sponsor
Massachusetts General Hospital
Other
Eligibility
18 Years to 65 Years
Enrollment
130 participants
Healthy volunteers
Accepts healthy volunteers
Timeline
2005 – 2006
U.S. locations
1
States / cities
Boston, Massachusetts