{
  "api_version": "1",
  "request": {
    "url": "https://clinicaltrialsfind.com/api/v1/search.json?intervention=Vitamin+D+Supplement",
    "query": {
      "intervention": "Vitamin D Supplement"
    },
    "page_size": 10
  },
  "pagination": {
    "page": 1,
    "page_size": 10,
    "total_count": 203,
    "total_pages": 21,
    "next_page_url": "https://clinicaltrialsfind.com/api/v1/search.json?intervention=Vitamin+D+Supplement&page=2&page_size=10",
    "previous_page_url": null
  },
  "source": "remote",
  "last_synced_at": "2026-09-09T21:31:23.564Z",
  "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": "NCT00550563",
      "title": "DNA Changes That Affect Vitamin D Metabolism in Patients With Colorectal Cancer Receiving Vitamin D Supplements",
      "overall_status": "COMPLETED",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "NA"
      ],
      "conditions": [
        "Colorectal Cancer"
      ],
      "interventions": [
        {
          "name": "cholecalciferol",
          "type": "DIETARY_SUPPLEMENT"
        },
        {
          "name": "polymerase chain reaction",
          "type": "GENETIC"
        },
        {
          "name": "polymorphism analysis",
          "type": "GENETIC"
        },
        {
          "name": "protein expression analysis",
          "type": "GENETIC"
        },
        {
          "name": "reverse transcriptase-polymerase chain reaction",
          "type": "GENETIC"
        },
        {
          "name": "western blotting",
          "type": "GENETIC"
        },
        {
          "name": "high performance liquid chromatography",
          "type": "OTHER"
        },
        {
          "name": "laboratory biomarker analysis",
          "type": "OTHER"
        },
        {
          "name": "pharmacological study",
          "type": "OTHER"
        },
        {
          "name": "adjuvant therapy",
          "type": "PROCEDURE"
        },
        {
          "name": "immunoscintigraphy",
          "type": "PROCEDURE"
        }
      ],
      "intervention_types": [
        "DIETARY_SUPPLEMENT",
        "GENETIC",
        "OTHER",
        "PROCEDURE"
      ],
      "sponsor": "Roswell Park Cancer Institute",
      "sponsor_class": "OTHER",
      "healthy_volunteers": false,
      "eligibility": {
        "minimum_age": "18 Years",
        "maximum_age": "120 Years",
        "sex": "ALL",
        "summary": "18 Years to 120 Years"
      },
      "enrollment_count": 50,
      "start_date": "2007-08",
      "completion_date": "2010-07",
      "has_results": false,
      "last_update_posted_date": "2017-04-04",
      "last_synced_at": "2026-09-09T21:31:23.564Z",
      "location_count": 1,
      "location_summary": "Buffalo, New York",
      "locations": [
        {
          "city": "Buffalo",
          "state": "New York"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT00550563"
    },
    {
      "nct_id": "NCT04720833",
      "title": "Effect of Dried Plum on Bone and Markers of Bone Status in Men",
      "overall_status": "COMPLETED",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "NA"
      ],
      "conditions": [
        "Osteoporosis",
        "Osteopenia"
      ],
      "interventions": [
        {
          "name": "dried plum",
          "type": "DIETARY_SUPPLEMENT"
        },
        {
          "name": "Calcium and vitamin D",
          "type": "DIETARY_SUPPLEMENT"
        }
      ],
      "intervention_types": [
        "DIETARY_SUPPLEMENT"
      ],
      "sponsor": "San Diego State University",
      "sponsor_class": "OTHER",
      "healthy_volunteers": true,
      "eligibility": {
        "minimum_age": "50 Years",
        "maximum_age": "79 Years",
        "sex": "MALE",
        "summary": "50 Years to 79 Years · Male only"
      },
      "enrollment_count": 66,
      "start_date": "2016-09-16",
      "completion_date": "2019-12-15",
      "has_results": false,
      "last_update_posted_date": "2021-01-22",
      "last_synced_at": "2026-09-09T21:31:23.564Z",
      "location_count": 1,
      "location_summary": "San Diego, California",
      "locations": [
        {
          "city": "San Diego",
          "state": "California"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT04720833"
    },
    {
      "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": "2026-09-09T21:31:23.564Z",
      "location_count": 1,
      "location_summary": "Augusta, Georgia",
      "locations": [
        {
          "city": "Augusta",
          "state": "Georgia"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT04386577"
    },
    {
      "nct_id": "NCT00043719",
      "title": "Nitroglycerin Ointment for Preventing Bone Loss in Postmenopausal Women",
      "overall_status": "COMPLETED",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "PHASE3"
      ],
      "conditions": [
        "Osteoporosis",
        "Osteopenia"
      ],
      "interventions": [
        {
          "name": "Nitroglycerin ointment",
          "type": "DRUG"
        },
        {
          "name": "Calcium supplement with vitamin D",
          "type": "DRUG"
        }
      ],
      "intervention_types": [
        "DRUG"
      ],
      "sponsor": "National Institute of Arthritis and Musculoskeletal and Skin Diseases (NIAMS)",
      "sponsor_class": "NIH",
      "healthy_volunteers": true,
      "eligibility": {
        "minimum_age": "40 Years",
        "maximum_age": "65 Years",
        "sex": "FEMALE",
        "summary": "40 Years to 65 Years · Female only"
      },
      "enrollment_count": 200,
      "start_date": "2002-07",
      "completion_date": "2007-12",
      "has_results": false,
      "last_update_posted_date": "2009-02-02",
      "last_synced_at": "2026-09-09T21:31:23.564Z",
      "location_count": 1,
      "location_summary": "New Brunswick, New Jersey",
      "locations": [
        {
          "city": "New Brunswick",
          "state": "New Jersey"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT00043719"
    },
    {
      "nct_id": "NCT02649192",
      "title": "Influenza Virus Vaccine Plus Vitamin A and D Supplements for Prevention of Respiratory Virus Infections in Children",
      "overall_status": "COMPLETED",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "PHASE2"
      ],
      "conditions": [
        "Healthy Participants"
      ],
      "interventions": [
        {
          "name": "Influenza virus vaccine",
          "type": "BIOLOGICAL"
        },
        {
          "name": "Vitamins A and D",
          "type": "DIETARY_SUPPLEMENT"
        },
        {
          "name": "Placebo",
          "type": "OTHER"
        }
      ],
      "intervention_types": [
        "BIOLOGICAL",
        "DIETARY_SUPPLEMENT",
        "OTHER"
      ],
      "sponsor": "St. Jude Children's Research Hospital",
      "sponsor_class": "OTHER",
      "healthy_volunteers": true,
      "eligibility": {
        "minimum_age": "2 Years",
        "maximum_age": "8 Years",
        "sex": "ALL",
        "summary": "2 Years to 8 Years"
      },
      "enrollment_count": 87,
      "start_date": "2016-01-21",
      "completion_date": "2018-06-29",
      "has_results": true,
      "last_update_posted_date": "2019-10-29",
      "last_synced_at": "2026-09-09T21:31:23.564Z",
      "location_count": 1,
      "location_summary": "Memphis, Tennessee",
      "locations": [
        {
          "city": "Memphis",
          "state": "Tennessee"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT02649192"
    },
    {
      "nct_id": "NCT00302627",
      "title": "Pamidronate, Vitamin D, and Calcium for the Bone Disease of Kidney and Heart Transplantation",
      "overall_status": "COMPLETED",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "NA"
      ],
      "conditions": [
        "Transplant Bone Disease"
      ],
      "interventions": [
        {
          "name": "Pamidronate",
          "type": "DRUG"
        },
        {
          "name": "vitamin D",
          "type": "DRUG"
        },
        {
          "name": "Calcium Carbonate",
          "type": "DRUG"
        }
      ],
      "intervention_types": [
        "DRUG"
      ],
      "sponsor": "Providence Health & Services",
      "sponsor_class": "OTHER",
      "healthy_volunteers": false,
      "eligibility": {
        "minimum_age": "18 Years",
        "maximum_age": null,
        "sex": "ALL",
        "summary": "18 Years and older"
      },
      "enrollment_count": 43,
      "start_date": "1999-01",
      "completion_date": "2002-11",
      "has_results": false,
      "last_update_posted_date": "2018-08-29",
      "last_synced_at": "2026-09-09T21:31:23.564Z",
      "location_count": 1,
      "location_summary": "Spokane, Washington",
      "locations": [
        {
          "city": "Spokane",
          "state": "Washington"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT00302627"
    },
    {
      "nct_id": "NCT04355572",
      "title": "Evaluation of the Clinical and Psychological Impact of Vitamin D Replacement in Adolescent Females at Risk for Polycystic Ovarian Syndrome (PCOS)",
      "overall_status": "RECRUITING",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "NA"
      ],
      "conditions": [
        "Polycystic Ovarian Syndrome in Adolescent Females",
        "Vitamin D Deficiency"
      ],
      "interventions": [
        {
          "name": "Vitamin D 4000IU daily",
          "type": "DRUG"
        },
        {
          "name": "Placebo",
          "type": "DRUG"
        }
      ],
      "intervention_types": [
        "DRUG"
      ],
      "sponsor": "Yale University",
      "sponsor_class": "OTHER",
      "healthy_volunteers": false,
      "eligibility": {
        "minimum_age": "13 Years",
        "maximum_age": "21 Years",
        "sex": "FEMALE",
        "summary": "13 Years to 21 Years · Female only"
      },
      "enrollment_count": 60,
      "start_date": "2026-09",
      "completion_date": "2028-08-31",
      "has_results": false,
      "last_update_posted_date": "2026-08-20",
      "last_synced_at": "2026-09-09T21:31:23.564Z",
      "location_count": 1,
      "location_summary": "New Haven, Connecticut",
      "locations": [
        {
          "city": "New Haven",
          "state": "Connecticut"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT04355572"
    },
    {
      "nct_id": "NCT02421887",
      "title": "Males, Antioxidants, and Infertility Trial",
      "overall_status": "COMPLETED",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "PHASE2"
      ],
      "conditions": [
        "Male Infertility"
      ],
      "interventions": [
        {
          "name": "Antioxidant Supplement",
          "type": "DRUG"
        },
        {
          "name": "Placebo",
          "type": "OTHER"
        }
      ],
      "intervention_types": [
        "DRUG",
        "OTHER"
      ],
      "sponsor": "Yale University",
      "sponsor_class": "OTHER",
      "healthy_volunteers": false,
      "eligibility": {
        "minimum_age": "18 Years",
        "maximum_age": null,
        "sex": "MALE",
        "summary": "18 Years and older · Male only"
      },
      "enrollment_count": 171,
      "start_date": "2015-12",
      "completion_date": "2018-12",
      "has_results": true,
      "last_update_posted_date": "2019-09-04",
      "last_synced_at": "2026-09-09T21:31:23.564Z",
      "location_count": 10,
      "location_summary": "Los Angeles, California • San Francisco, California • Sunnyvale, California + 7 more",
      "locations": [
        {
          "city": "Los Angeles",
          "state": "California"
        },
        {
          "city": "San Francisco",
          "state": "California"
        },
        {
          "city": "Sunnyvale",
          "state": "California"
        },
        {
          "city": "Augusta",
          "state": "Georgia"
        },
        {
          "city": "Southfield",
          "state": "Michigan"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT02421887"
    },
    {
      "nct_id": "NCT01394484",
      "title": "Dairy Foods Compared to Dietary Supplements and Bone Health",
      "overall_status": "COMPLETED",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "NA"
      ],
      "conditions": [
        "Osteoporosis",
        "Bone Loss",
        "Osteopenia"
      ],
      "interventions": [
        {
          "name": "Intervention I",
          "type": "OTHER"
        },
        {
          "name": "Intervention II",
          "type": "DIETARY_SUPPLEMENT"
        }
      ],
      "intervention_types": [
        "OTHER",
        "DIETARY_SUPPLEMENT"
      ],
      "sponsor": "USDA, Western Human Nutrition Research Center",
      "sponsor_class": "FED",
      "healthy_volunteers": true,
      "eligibility": {
        "minimum_age": "50 Years",
        "maximum_age": "65 Years",
        "sex": "FEMALE",
        "summary": "50 Years to 65 Years · Female only"
      },
      "enrollment_count": 12,
      "start_date": "2010-12",
      "completion_date": "2013-02",
      "has_results": false,
      "last_update_posted_date": "2013-02-26",
      "last_synced_at": "2026-09-09T21:31:23.564Z",
      "location_count": 1,
      "location_summary": "Davis, California",
      "locations": [
        {
          "city": "Davis",
          "state": "California"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT01394484"
    },
    {
      "nct_id": "NCT01385098",
      "title": "Efficacy of Vitamin D Supplementation in Bariatric Surgery Patients",
      "overall_status": "COMPLETED",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "NA"
      ],
      "conditions": [
        "Obesity",
        "Vitamin D Deficiency"
      ],
      "interventions": [
        {
          "name": "Vitamin D3 and Calcium",
          "type": "DIETARY_SUPPLEMENT"
        }
      ],
      "intervention_types": [
        "DIETARY_SUPPLEMENT"
      ],
      "sponsor": "Vadim Sherman, MD",
      "sponsor_class": "OTHER",
      "healthy_volunteers": true,
      "eligibility": {
        "minimum_age": "18 Years",
        "maximum_age": "65 Years",
        "sex": "FEMALE",
        "summary": "18 Years to 65 Years · Female only"
      },
      "enrollment_count": 37,
      "start_date": "2011-07",
      "completion_date": "2015-09",
      "has_results": true,
      "last_update_posted_date": "2018-01-23",
      "last_synced_at": "2026-09-09T21:31:23.564Z",
      "location_count": 1,
      "location_summary": "Houston, Texas",
      "locations": [
        {
          "city": "Houston",
          "state": "Texas"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT01385098"
    }
  ]
}