{
  "api_version": "1",
  "request": {
    "url": "https://clinicaltrialsfind.com/api/v1/search.json?condition=Vitamin+D3",
    "query": {
      "condition": "Vitamin D3"
    },
    "page_size": 10
  },
  "pagination": {
    "page": 1,
    "page_size": 10,
    "total_count": 767,
    "total_pages": 77,
    "next_page_url": "https://clinicaltrialsfind.com/api/v1/search.json?condition=Vitamin+D3&page=2&page_size=10",
    "previous_page_url": null
  },
  "source": "remote",
  "last_synced_at": "2026-09-19T15:45:05.045Z",
  "attribution": "Data derived from public ClinicalTrials.gov records. The official record at https://clinicaltrials.gov/ remains the source of truth for current availability, contacts, and full study details.",
  "notes": [
    "This endpoint exposes only public summary fields — no participant contact emails, phone numbers, or scraped investigator contact details.",
    "For contact information and full protocol detail, follow each trial's `official_url` to the ClinicalTrials.gov record.",
    "This API is a navigational aid. It does not provide medical advice, eligibility determinations, or compensation guarantees."
  ],
  "trials": [
    {
      "nct_id": "NCT01593501",
      "title": "How Does Magnesium Status Influence Calcium Homeostasis?",
      "overall_status": "COMPLETED",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "PHASE4"
      ],
      "conditions": [
        "Magnesium Deficiency",
        "Calcium Metabolism Disorders"
      ],
      "interventions": [
        {
          "name": "vitamin D3",
          "type": "DIETARY_SUPPLEMENT"
        }
      ],
      "intervention_types": [
        "DIETARY_SUPPLEMENT"
      ],
      "sponsor": "University of Wisconsin, Madison",
      "sponsor_class": "OTHER",
      "healthy_volunteers": true,
      "eligibility": {
        "minimum_age": "30 Years",
        "maximum_age": "75 Years",
        "sex": "FEMALE",
        "summary": "30 Years to 75 Years · Female only"
      },
      "enrollment_count": 39,
      "start_date": "2012-05",
      "completion_date": "2014-08",
      "has_results": false,
      "last_update_posted_date": "2016-11-01",
      "last_synced_at": "2026-09-19T15:45:05.045Z",
      "location_count": 1,
      "location_summary": "Madison, Wisconsin",
      "locations": [
        {
          "city": "Madison",
          "state": "Wisconsin"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT01593501"
    },
    {
      "nct_id": "NCT03649802",
      "title": "Vitamin D and Arterial Stiffness in Elderly",
      "overall_status": "COMPLETED",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "PHASE2"
      ],
      "conditions": [
        "Vitamin D Deficiency",
        "Arterial Stiffness"
      ],
      "interventions": [
        {
          "name": "Low dose vitamin D3",
          "type": "DIETARY_SUPPLEMENT"
        },
        {
          "name": "High dose vitamin D3",
          "type": "DIETARY_SUPPLEMENT"
        }
      ],
      "intervention_types": [
        "DIETARY_SUPPLEMENT"
      ],
      "sponsor": "Texas Tech University Health Sciences Center",
      "sponsor_class": "OTHER",
      "healthy_volunteers": true,
      "eligibility": {
        "minimum_age": "65 Years",
        "maximum_age": "89 Years",
        "sex": "ALL",
        "summary": "65 Years to 89 Years"
      },
      "enrollment_count": 52,
      "start_date": "2018-08-16",
      "completion_date": "2021-12-31",
      "has_results": false,
      "last_update_posted_date": "2022-03-21",
      "last_synced_at": "2026-09-19T15:45:05.045Z",
      "location_count": 1,
      "location_summary": "Lubbock, Texas",
      "locations": [
        {
          "city": "Lubbock",
          "state": "Texas"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT03649802"
    },
    {
      "nct_id": "NCT01351805",
      "title": "Vitamin D and Fish Oil for Autoimmune Disease, Inflammation and Knee Pain",
      "overall_status": "COMPLETED",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "NA"
      ],
      "conditions": [
        "Autoimmune Diseases",
        "Systemic Inflammatory Process",
        "Knee Pain Chronic",
        "Osteoarthritis",
        "Rheumatoid Arthritis"
      ],
      "interventions": [
        {
          "name": "Fish Oil",
          "type": "DRUG"
        },
        {
          "name": "Vitamin D",
          "type": "DIETARY_SUPPLEMENT"
        },
        {
          "name": "placebo pill",
          "type": "OTHER"
        }
      ],
      "intervention_types": [
        "DRUG",
        "DIETARY_SUPPLEMENT",
        "OTHER"
      ],
      "sponsor": "Brigham and Women's Hospital",
      "sponsor_class": "OTHER",
      "healthy_volunteers": true,
      "eligibility": {
        "minimum_age": "50 Years",
        "maximum_age": null,
        "sex": "ALL",
        "summary": "50 Years and older"
      },
      "enrollment_count": 25871,
      "start_date": "2010-07",
      "completion_date": "2025-02",
      "has_results": true,
      "last_update_posted_date": "2025-12-03",
      "last_synced_at": "2026-09-19T15:45:05.045Z",
      "location_count": 1,
      "location_summary": "Boston, Massachusetts",
      "locations": [
        {
          "city": "Boston",
          "state": "Massachusetts"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT01351805"
    },
    {
      "nct_id": "NCT03176849",
      "title": "A Randomized Phase IV Control Trial of Single High Dose Oral Vitamin D3 in Pediatric Patients Undergoing HSCT",
      "overall_status": "COMPLETED",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "PHASE4"
      ],
      "conditions": [
        "Vitamin D Deficiency",
        "Stem Cell Transplant Complications",
        "Pediatric Cancer",
        "Blood Disorder",
        "Pediatric Acute Myeloid Leukemia",
        "Pediatric Acute Lymphoid Leukemia",
        "Myelodysplastic Syndromes",
        "Sickle Cell Anemia in Children",
        "Aplastic Anemia",
        "Thalassemia in Children"
      ],
      "interventions": [
        {
          "name": "Vitamin D3",
          "type": "DIETARY_SUPPLEMENT"
        },
        {
          "name": "Standard Vitamin D3 Supplementation",
          "type": "DIETARY_SUPPLEMENT"
        }
      ],
      "intervention_types": [
        "DIETARY_SUPPLEMENT"
      ],
      "sponsor": "Phoenix Children's Hospital",
      "sponsor_class": "OTHER",
      "healthy_volunteers": false,
      "eligibility": {
        "minimum_age": "1 Year",
        "maximum_age": "25 Years",
        "sex": "ALL",
        "summary": "1 Year to 25 Years"
      },
      "enrollment_count": 49,
      "start_date": "2017-11-01",
      "completion_date": "2019-07-01",
      "has_results": false,
      "last_update_posted_date": "2020-11-17",
      "last_synced_at": "2026-09-19T15:45:05.045Z",
      "location_count": 1,
      "location_summary": "Phoenix, Arizona",
      "locations": [
        {
          "city": "Phoenix",
          "state": "Arizona"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT03176849"
    },
    {
      "nct_id": "NCT00832533",
      "title": "The Response of Serum 25-Hydroxyvitamin D to Incidental Ultraviolet Light Exposure",
      "overall_status": "COMPLETED",
      "study_type": "OBSERVATIONAL",
      "phases": [],
      "conditions": [
        "Melanoma"
      ],
      "interventions": [],
      "intervention_types": [],
      "sponsor": "New Mexico Cancer Research Alliance",
      "sponsor_class": "OTHER",
      "healthy_volunteers": true,
      "eligibility": {
        "minimum_age": "18 Years",
        "maximum_age": null,
        "sex": "ALL",
        "summary": "18 Years and older"
      },
      "enrollment_count": 9,
      "start_date": "2008-11",
      "completion_date": "2010-01",
      "has_results": false,
      "last_update_posted_date": "2015-09-28",
      "last_synced_at": "2026-09-19T15:45:05.045Z",
      "location_count": 1,
      "location_summary": "Albuquerque, New Mexico",
      "locations": [
        {
          "city": "Albuquerque",
          "state": "New Mexico"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT00832533"
    },
    {
      "nct_id": "NCT02312687",
      "title": "Long-Term Extension Study of KRN23 in Adult Subjects With X-Linked Hypophosphatemia (XLH)",
      "overall_status": "COMPLETED",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "PHASE2"
      ],
      "conditions": [
        "X-Linked Hypophosphatemia"
      ],
      "interventions": [
        {
          "name": "KRN23",
          "type": "BIOLOGICAL"
        }
      ],
      "intervention_types": [
        "BIOLOGICAL"
      ],
      "sponsor": "Kyowa Kirin, Inc.",
      "sponsor_class": "INDUSTRY",
      "healthy_volunteers": false,
      "eligibility": {
        "minimum_age": null,
        "maximum_age": null,
        "sex": "ALL",
        "summary": "Not listed"
      },
      "enrollment_count": 20,
      "start_date": "2015-01-30",
      "completion_date": "2018-11-30",
      "has_results": true,
      "last_update_posted_date": "2024-05-06",
      "last_synced_at": "2026-09-19T15:45:05.045Z",
      "location_count": 5,
      "location_summary": "San Francisco, California • New Haven, Connecticut • Indianapolis, Indiana + 2 more",
      "locations": [
        {
          "city": "San Francisco",
          "state": "California"
        },
        {
          "city": "New Haven",
          "state": "Connecticut"
        },
        {
          "city": "Indianapolis",
          "state": "Indiana"
        },
        {
          "city": "Durham",
          "state": "North Carolina"
        },
        {
          "city": "Houston",
          "state": "Texas"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT02312687"
    },
    {
      "nct_id": "NCT02043171",
      "title": "Nutritional Intervention for Age-related Muscular Function and Strength Losses-Study 2",
      "overall_status": "COMPLETED",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "PHASE1"
      ],
      "conditions": [
        "Sarcopenia"
      ],
      "interventions": [
        {
          "name": "Placebo",
          "type": "DIETARY_SUPPLEMENT"
        },
        {
          "name": "HMB plus Vitamin D",
          "type": "DRUG"
        },
        {
          "name": "Non-Exercise",
          "type": "BEHAVIORAL"
        },
        {
          "name": "Exercise",
          "type": "BEHAVIORAL"
        }
      ],
      "intervention_types": [
        "DIETARY_SUPPLEMENT",
        "DRUG",
        "BEHAVIORAL"
      ],
      "sponsor": "Metabolic Technologies Inc.",
      "sponsor_class": "INDUSTRY",
      "healthy_volunteers": true,
      "eligibility": {
        "minimum_age": "60 Years",
        "maximum_age": null,
        "sex": "ALL",
        "summary": "60 Years and older"
      },
      "enrollment_count": 238,
      "start_date": "2014-08",
      "completion_date": "2019-02-04",
      "has_results": false,
      "last_update_posted_date": "2019-02-11",
      "last_synced_at": "2026-09-19T15:45:05.045Z",
      "location_count": 1,
      "location_summary": "Ames, Iowa",
      "locations": [
        {
          "city": "Ames",
          "state": "Iowa"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT02043171"
    },
    {
      "nct_id": "NCT02360644",
      "title": "Drug Metabolizing Enzyme and Transporter Function in Chronic Kidney Disease",
      "overall_status": "COMPLETED",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "NA"
      ],
      "conditions": [
        "Chronic Kidney Diseases",
        "Deficiency, Vitamin D"
      ],
      "interventions": [
        {
          "name": "Cholecalciferol",
          "type": "DIETARY_SUPPLEMENT"
        }
      ],
      "intervention_types": [
        "DIETARY_SUPPLEMENT"
      ],
      "sponsor": "University of Colorado, Denver",
      "sponsor_class": "OTHER",
      "healthy_volunteers": true,
      "eligibility": {
        "minimum_age": "18 Years",
        "maximum_age": "70 Years",
        "sex": "ALL",
        "summary": "18 Years to 70 Years"
      },
      "enrollment_count": 23,
      "start_date": "2014-10",
      "completion_date": "2019-02-01",
      "has_results": false,
      "last_update_posted_date": "2021-06-30",
      "last_synced_at": "2026-09-19T15:45:05.045Z",
      "location_count": 2,
      "location_summary": "Aurora, Colorado • Pittsburgh, Pennsylvania",
      "locations": [
        {
          "city": "Aurora",
          "state": "Colorado"
        },
        {
          "city": "Pittsburgh",
          "state": "Pennsylvania"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT02360644"
    },
    {
      "nct_id": "NCT01443897",
      "title": "Effect of Consumption of Post-harvest UV-B Treated Mushrooms on Vitamin D Status of Healthy Adults",
      "overall_status": "COMPLETED",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "NA"
      ],
      "conditions": [
        "Vitamin D Deficiency"
      ],
      "interventions": [
        {
          "name": "1,000 IU vitamin D2",
          "type": "DIETARY_SUPPLEMENT"
        },
        {
          "name": "placebo capsule",
          "type": "DIETARY_SUPPLEMENT"
        },
        {
          "name": "mushrooms",
          "type": "OTHER"
        },
        {
          "name": "UVB-treated mushrooms, 400 IU vitamin D2",
          "type": "OTHER"
        },
        {
          "name": "UVB-treated mushrooms, 1,000 IU vitamin D2",
          "type": "OTHER"
        }
      ],
      "intervention_types": [
        "DIETARY_SUPPLEMENT",
        "OTHER"
      ],
      "sponsor": "USDA, Western Human Nutrition Research Center",
      "sponsor_class": "FED",
      "healthy_volunteers": true,
      "eligibility": {
        "minimum_age": "20 Years",
        "maximum_age": "59 Years",
        "sex": "ALL",
        "summary": "20 Years to 59 Years"
      },
      "enrollment_count": 48,
      "start_date": "2010-05",
      "completion_date": "2011-06",
      "has_results": false,
      "last_update_posted_date": "2011-09-30",
      "last_synced_at": "2026-09-19T15:45:05.045Z",
      "location_count": 1,
      "location_summary": "Davis, California",
      "locations": [
        {
          "city": "Davis",
          "state": "California"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT01443897"
    },
    {
      "nct_id": "NCT01169259",
      "title": "Vitamin D and Omega-3 Trial (VITAL)",
      "overall_status": "ACTIVE_NOT_RECRUITING",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "PHASE3"
      ],
      "conditions": [
        "Cancer",
        "Cardiovascular Disease"
      ],
      "interventions": [
        {
          "name": "vitamin D3",
          "type": "DIETARY_SUPPLEMENT"
        },
        {
          "name": "omega-3 fatty acids (fish oil)",
          "type": "DRUG"
        },
        {
          "name": "Vitamin D3 placebo",
          "type": "DIETARY_SUPPLEMENT"
        },
        {
          "name": "Fish oil placebo",
          "type": "DIETARY_SUPPLEMENT"
        }
      ],
      "intervention_types": [
        "DIETARY_SUPPLEMENT",
        "DRUG"
      ],
      "sponsor": "Brigham and Women's Hospital",
      "sponsor_class": "OTHER",
      "healthy_volunteers": true,
      "eligibility": {
        "minimum_age": "50 Years",
        "maximum_age": null,
        "sex": "ALL",
        "summary": "50 Years and older"
      },
      "enrollment_count": 25871,
      "start_date": "2010-07",
      "completion_date": "2026-10",
      "has_results": true,
      "last_update_posted_date": "2026-07-30",
      "last_synced_at": "2026-09-19T15:45:05.045Z",
      "location_count": 1,
      "location_summary": "Boston, Massachusetts",
      "locations": [
        {
          "city": "Boston",
          "state": "Massachusetts"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT01169259"
    }
  ]
}