{
  "api_version": "1",
  "request": {
    "url": "https://clinicaltrialsfind.com/api/v1/search.json?intervention=Vitamin+D3+supplementation",
    "query": {
      "intervention": "Vitamin D3 supplementation"
    },
    "page_size": 10
  },
  "pagination": {
    "page": 1,
    "page_size": 10,
    "total_count": 267,
    "total_pages": 27,
    "next_page_url": "https://clinicaltrialsfind.com/api/v1/search.json?intervention=Vitamin+D3+supplementation&page=2&page_size=10",
    "previous_page_url": null
  },
  "source": "remote",
  "last_synced_at": "2026-09-26T08:46:54.936Z",
  "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": "NCT03739671",
      "title": "Vitamin D Supplementation and Effects on Mood in Emergency Medicine Residents",
      "overall_status": "COMPLETED",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "NA"
      ],
      "conditions": [
        "Seasonal Mood Disorder"
      ],
      "interventions": [
        {
          "name": "Vitamin D",
          "type": "DIETARY_SUPPLEMENT"
        },
        {
          "name": "No Vitamin D",
          "type": "DIETARY_SUPPLEMENT"
        }
      ],
      "intervention_types": [
        "DIETARY_SUPPLEMENT"
      ],
      "sponsor": "Corewell Health South",
      "sponsor_class": "OTHER",
      "healthy_volunteers": true,
      "eligibility": {
        "minimum_age": "18 Years",
        "maximum_age": null,
        "sex": "ALL",
        "summary": "18 Years and older"
      },
      "enrollment_count": 27,
      "start_date": "2018-10-01",
      "completion_date": "2020-04-30",
      "has_results": false,
      "last_update_posted_date": "2024-11-29",
      "last_synced_at": "2026-09-26T08:46:54.936Z",
      "location_count": 1,
      "location_summary": "Saint Joseph, Michigan",
      "locations": [
        {
          "city": "Saint Joseph",
          "state": "Michigan"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT03739671"
    },
    {
      "nct_id": "NCT01630213",
      "title": "Impact of Vitamin D Supplementation on Cardiac Structure and Function",
      "overall_status": "COMPLETED",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "NA"
      ],
      "conditions": [
        "Cardiovascular Disease"
      ],
      "interventions": [
        {
          "name": "Vitamin D3 + fish oil/fish oil placebo",
          "type": "DIETARY_SUPPLEMENT"
        },
        {
          "name": "Vitamin D3 placebo + fish oil/fish oil placebo",
          "type": "DIETARY_SUPPLEMENT"
        }
      ],
      "intervention_types": [
        "DIETARY_SUPPLEMENT"
      ],
      "sponsor": "Massachusetts General Hospital",
      "sponsor_class": "OTHER",
      "healthy_volunteers": true,
      "eligibility": {
        "minimum_age": "50 Years",
        "maximum_age": null,
        "sex": "ALL",
        "summary": "50 Years and older"
      },
      "enrollment_count": 1025,
      "start_date": "2010-07-01",
      "completion_date": "2021-06-30",
      "has_results": false,
      "last_update_posted_date": "2022-04-06",
      "last_synced_at": "2026-09-26T08:46:54.936Z",
      "location_count": 1,
      "location_summary": "Boston, Massachusetts",
      "locations": [
        {
          "city": "Boston",
          "state": "Massachusetts"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT01630213"
    },
    {
      "nct_id": "NCT02802449",
      "title": "To Study the Nutri-Genomic Response of Vit-D Supplementation in African-Americans",
      "overall_status": "COMPLETED",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "NA"
      ],
      "conditions": [
        "Hypovitaminosis D"
      ],
      "interventions": [
        {
          "name": "25 Hydroxy- Vitamin D3 [25 (OH) D3]",
          "type": "DRUG"
        },
        {
          "name": "Placebo",
          "type": "DRUG"
        }
      ],
      "intervention_types": [
        "DRUG"
      ],
      "sponsor": "Charles Drew University of Medicine and Science",
      "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": 330,
      "start_date": "2013-09",
      "completion_date": "2018-07",
      "has_results": true,
      "last_update_posted_date": "2019-02-15",
      "last_synced_at": "2026-09-26T08:46:54.936Z",
      "location_count": 1,
      "location_summary": "Los Angeles, California",
      "locations": [
        {
          "city": "Los Angeles",
          "state": "California"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT02802449"
    },
    {
      "nct_id": "NCT01240265",
      "title": "Vitamin D Supplementation in Breastfeeding Women",
      "overall_status": "COMPLETED",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "PHASE2",
        "PHASE3"
      ],
      "conditions": [
        "Vitamin D Deficiency",
        "Rickets",
        "Infant Nutrition Disorders"
      ],
      "interventions": [
        {
          "name": "Vitamin D3",
          "type": "DIETARY_SUPPLEMENT"
        }
      ],
      "intervention_types": [
        "DIETARY_SUPPLEMENT"
      ],
      "sponsor": "Mayo Clinic",
      "sponsor_class": "OTHER",
      "healthy_volunteers": true,
      "eligibility": {
        "minimum_age": "1 Month",
        "maximum_age": "50 Years",
        "sex": "ALL",
        "summary": "1 Month to 50 Years"
      },
      "enrollment_count": 80,
      "start_date": "2010-12",
      "completion_date": "2011-08",
      "has_results": false,
      "last_update_posted_date": "2013-04-30",
      "last_synced_at": "2026-09-26T08:46:54.936Z",
      "location_count": 1,
      "location_summary": "Rochester, Minnesota",
      "locations": [
        {
          "city": "Rochester",
          "state": "Minnesota"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT01240265"
    },
    {
      "nct_id": "NCT04386577",
      "title": "Effects of Vitamin D and Omega-3 Supplementation on Telomeres in VITAL",
      "overall_status": "UNKNOWN",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "PHASE3"
      ],
      "conditions": [
        "Aging"
      ],
      "interventions": [
        {
          "name": "Vitamin D3 (cholecalciferol)",
          "type": "DIETARY_SUPPLEMENT"
        },
        {
          "name": "fish oil",
          "type": "DRUG"
        }
      ],
      "intervention_types": [
        "DIETARY_SUPPLEMENT",
        "DRUG"
      ],
      "sponsor": "Augusta University",
      "sponsor_class": "OTHER",
      "healthy_volunteers": true,
      "eligibility": {
        "minimum_age": "50 Years",
        "maximum_age": null,
        "sex": "ALL",
        "summary": "50 Years and older"
      },
      "enrollment_count": 1054,
      "start_date": "2016-08-19",
      "completion_date": "2021-04-30",
      "has_results": false,
      "last_update_posted_date": "2020-05-13",
      "last_synced_at": "2026-09-26T08:46:54.936Z",
      "location_count": 1,
      "location_summary": "Augusta, Georgia",
      "locations": [
        {
          "city": "Augusta",
          "state": "Georgia"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT04386577"
    },
    {
      "nct_id": "NCT03070483",
      "title": "Blood Pressure in Blacks and Calcium (BBC) and Vitamin D Study",
      "overall_status": "COMPLETED",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "PHASE2"
      ],
      "conditions": [
        "Hypertension",
        "Vitamin D Deficiency"
      ],
      "interventions": [
        {
          "name": "Cholecalciferol",
          "type": "DRUG"
        }
      ],
      "intervention_types": [
        "DRUG"
      ],
      "sponsor": "Loyola University",
      "sponsor_class": "OTHER",
      "healthy_volunteers": true,
      "eligibility": {
        "minimum_age": "25 Years",
        "maximum_age": "45 Years",
        "sex": "ALL",
        "summary": "25 Years to 45 Years"
      },
      "enrollment_count": 5,
      "start_date": "2018-03-25",
      "completion_date": "2018-11-01",
      "has_results": true,
      "last_update_posted_date": "2020-06-24",
      "last_synced_at": "2026-09-26T08:46:54.936Z",
      "location_count": 1,
      "location_summary": "Maywood, Illinois",
      "locations": [
        {
          "city": "Maywood",
          "state": "Illinois"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT03070483"
    },
    {
      "nct_id": "NCT01473602",
      "title": "Second Study of the Effect of Teriparatide on Hip Fracture Healing",
      "overall_status": "COMPLETED",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "PHASE3"
      ],
      "conditions": [
        "Femur Neck Fracture"
      ],
      "interventions": [
        {
          "name": "Teriparatide",
          "type": "DRUG"
        },
        {
          "name": "Placebo",
          "type": "DRUG"
        },
        {
          "name": "Calcium supplementation",
          "type": "DIETARY_SUPPLEMENT"
        },
        {
          "name": "Vitamin D supplementation",
          "type": "DIETARY_SUPPLEMENT"
        }
      ],
      "intervention_types": [
        "DRUG",
        "DIETARY_SUPPLEMENT"
      ],
      "sponsor": "Eli Lilly and Company",
      "sponsor_class": "INDUSTRY",
      "healthy_volunteers": false,
      "eligibility": {
        "minimum_age": "50 Years",
        "maximum_age": null,
        "sex": "ALL",
        "summary": "50 Years and older"
      },
      "enrollment_count": 39,
      "start_date": "2012-01",
      "completion_date": "2013-11",
      "has_results": true,
      "last_update_posted_date": "2015-04-16",
      "last_synced_at": "2026-09-26T08:46:54.936Z",
      "location_count": 19,
      "location_summary": "San Diego, California • Golden, Colorado • Washington D.C., District of Columbia + 16 more",
      "locations": [
        {
          "city": "San Diego",
          "state": "California"
        },
        {
          "city": "Golden",
          "state": "Colorado"
        },
        {
          "city": "Washington D.C.",
          "state": "District of Columbia"
        },
        {
          "city": "Gainesville",
          "state": "Georgia"
        },
        {
          "city": "Morton Grove",
          "state": "Illinois"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT01473602"
    },
    {
      "nct_id": "NCT05522179",
      "title": "Nutritional Supplements and Foot Surgery",
      "overall_status": "COMPLETED",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "NA"
      ],
      "conditions": [
        "Foot Injuries and Disorders"
      ],
      "interventions": [
        {
          "name": "NutraHeal",
          "type": "DIETARY_SUPPLEMENT"
        },
        {
          "name": "NutraHeal Plus",
          "type": "DIETARY_SUPPLEMENT"
        }
      ],
      "intervention_types": [
        "DIETARY_SUPPLEMENT"
      ],
      "sponsor": "NutraHeal",
      "sponsor_class": "INDUSTRY",
      "healthy_volunteers": false,
      "eligibility": {
        "minimum_age": "20 Years",
        "maximum_age": "80 Years",
        "sex": "ALL",
        "summary": "20 Years to 80 Years"
      },
      "enrollment_count": 46,
      "start_date": "2022-08-29",
      "completion_date": "2023-07-30",
      "has_results": false,
      "last_update_posted_date": "2023-08-01",
      "last_synced_at": "2026-09-26T08:46:54.936Z",
      "location_count": 3,
      "location_summary": "Altoona, Pennsylvania • Ebensburg, Pennsylvania • State College, Pennsylvania",
      "locations": [
        {
          "city": "Altoona",
          "state": "Pennsylvania"
        },
        {
          "city": "Ebensburg",
          "state": "Pennsylvania"
        },
        {
          "city": "State College",
          "state": "Pennsylvania"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT05522179"
    },
    {
      "nct_id": "NCT02132442",
      "title": "Hepatic Dysfunction, Vitamin D Status, and Glycemic Control in Diabetes",
      "overall_status": "COMPLETED",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "PHASE3"
      ],
      "conditions": [
        "Type 2 Diabetes",
        "Nonalcoholic Fatty Liver Disease",
        "Vitamin D Deficiency"
      ],
      "interventions": [
        {
          "name": "Ergocalciferol, placebo",
          "type": "DIETARY_SUPPLEMENT"
        }
      ],
      "intervention_types": [
        "DIETARY_SUPPLEMENT"
      ],
      "sponsor": "University of Massachusetts, Worcester",
      "sponsor_class": "OTHER",
      "healthy_volunteers": false,
      "eligibility": {
        "minimum_age": "10 Years",
        "maximum_age": "50 Years",
        "sex": "ALL",
        "summary": "10 Years to 50 Years"
      },
      "enrollment_count": 12,
      "start_date": "2014-03",
      "completion_date": "2016-10",
      "has_results": false,
      "last_update_posted_date": "2017-01-10",
      "last_synced_at": "2026-09-26T08:46:54.936Z",
      "location_count": 1,
      "location_summary": "Worcester, Massachusetts",
      "locations": [
        {
          "city": "Worcester",
          "state": "Massachusetts"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT02132442"
    },
    {
      "nct_id": "NCT00858247",
      "title": "Effect of Vitamin D3 Supplementation on Insulin Resistance and Cardiovascular Risk Factors in Obese Adolescents",
      "overall_status": "COMPLETED",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "PHASE2"
      ],
      "conditions": [
        "Obesity"
      ],
      "interventions": [
        {
          "name": "Vitamin D3",
          "type": "DIETARY_SUPPLEMENT"
        }
      ],
      "intervention_types": [
        "DIETARY_SUPPLEMENT"
      ],
      "sponsor": "Mayo Clinic",
      "sponsor_class": "OTHER",
      "healthy_volunteers": true,
      "eligibility": {
        "minimum_age": "12 Years",
        "maximum_age": "18 Years",
        "sex": "ALL",
        "summary": "12 Years to 18 Years"
      },
      "enrollment_count": 51,
      "start_date": "2009-04",
      "completion_date": "2012-12",
      "has_results": true,
      "last_update_posted_date": "2014-05-20",
      "last_synced_at": "2026-09-26T08:46:54.936Z",
      "location_count": 1,
      "location_summary": "Rochester, Minnesota",
      "locations": [
        {
          "city": "Rochester",
          "state": "Minnesota"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT00858247"
    }
  ]
}