- 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
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Showing 1–24
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matching trials from the live ClinicalTrials.gov search.
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- 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
- 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
- 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
- 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
- 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
- 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
- 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
- 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
- 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
- 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
- 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
- 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
- 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