{"entity":{"id":"vital","kind":"trial","name":"VITAL (VITamin D and OmegA-3 TriaL)","aka":[],"tldr":"The definitive test of whether vitamin D or fish-oil pills prevent cancer or heart disease in healthy adults. They did not.","summary":"25,871 participants (including 5,106 Black participants) followed for a median 5.3 years. Vitamin D did not reduce invasive cancer incidence (793 vs 824 events, HR 0.96, 95% CI 0.88-1.06) or major cardiovascular events (HR 0.97); omega-3 did not reduce cancer (HR 1.03) or major cardiovascular events (HR 0.92), though it reduced myocardial infarction in secondary analysis. Total cancer mortality with vitamin D was HR 0.83 (0.67-1.02) overall and HR 0.75 (0.59-0.96) after excluding the first two years, a pre-specified but secondary analysis. Later ancillary analyses reported fewer advanced (metastatic or fatal) cancers with vitamin D, concentrated in normal-weight participants. The trial ended the hope of broad cancer prevention with supplements while leaving a testable mortality hypothesis.","status":"negative","asOf":"2026-09-08","links":[{"label":"ClinicalTrials.gov NCT01169259","url":"https://clinicaltrials.gov/study/NCT01169259"},{"label":"Vitamin D results (NEJM 2019)","url":"https://doi.org/10.1056/NEJMoa1809944"},{"label":"Omega-3 results (NEJM 2019)","url":"https://doi.org/10.1056/NEJMoa1809946"}],"tags":[],"related":["idea-reg-vitamin-d-digestive-cancer-biomarker-trial"],"cancers":[],"sections":["nutrition-lifestyle","prevention"],"technologies":["vitamin-d-omega3-supplementation","chemoprevention"],"targets":[],"drugs":[],"companies":[],"institutions":[],"pathways":[],"terms":["unproven-diet-claims","hazard-ratio"],"trials":[],"people":[],"bottlenecks":["b-negative-results","b-misinformation"],"keyPapers":["paper-manson-n-engl-j-med"],"journals":[],"dependsOn":[],"notes":[],"nct":"NCT01169259","phase":"3","setting":"Primary prevention in US adults (men 50+, women 55+) without prior cancer or cardiovascular disease: vitamin D3 2000 IU/day and/or marine omega-3 1 g/day vs placebo, 2x2 factorial","sponsor":"Brigham and Women's Hospital / NIH","result":"Invasive cancer incidence HR 0.96 (vitamin D), 1.03 (omega-3); no benefit on primary endpoints.","started":"2010-07","startedType":"actual","yearReported":2018,"enrolled":25871,"enrolledBasis":"registry","outcomes":[{"endpoint":"Invasive cancer of any type","primary":true,"unit":"events","arms":[{"name":"Vitamin D3","n":12927,"value":793},{"name":"Placebo","n":12944,"value":824}],"hr":0.96,"ci":[0.88,1.06],"p":"0.47","source":"https://doi.org/10.1056/NEJMoa1809944"},{"endpoint":"Invasive cancer of any type","primary":true,"unit":"events","arms":[{"name":"Omega-3","n":12933,"value":820},{"name":"Placebo","n":12938,"value":797}],"hr":1.03,"ci":[0.93,1.13],"source":"https://doi.org/10.1056/NEJMoa1809946"}],"replication":"Consistent with D-Health (Australia, 21,315 participants, no reduction in mortality or cancer) and with meta-analyses showing no effect on incidence and a possible 10-15% reduction in cancer mortality."},"route":"/trials/vital/","neighbours":{"idea":[{"id":"idea-reg-vitamin-d-digestive-cancer-biomarker-trial","kind":"idea","name":"A biomarker-directed trial of vitamin D after surgery for digestive tract cancers","route":"/ideas/idea-reg-vitamin-d-digestive-cancer-biomarker-trial/"}],"section":[{"id":"nutrition-lifestyle","kind":"section","name":"Diet, Exercise & Lifestyle","route":"/fronts/nutrition-lifestyle/"},{"id":"prevention","kind":"section","name":"Prevention & Risk","route":"/fronts/prevention/"}],"technology":[{"id":"chemoprevention","kind":"technology","name":"Chemoprevention & risk-reducing surgery","route":"/technologies/chemoprevention/"},{"id":"vitamin-d-omega3-supplementation","kind":"technology","name":"Vitamin D and omega-3 supplementation","route":"/technologies/vitamin-d-omega3-supplementation/"}],"term":[{"id":"hazard-ratio","kind":"term","name":"Hazard ratio (HR)","route":"/terms/hazard-ratio/"},{"id":"unproven-diet-claims","kind":"term","name":"Unproven diet claims (alkaline, juice, 'anti-cancer' diets)","route":"/terms/unproven-diet-claims/"}],"bottleneck":[{"id":"b-negative-results","kind":"bottleneck","name":"Failures are hidden","route":"/bottlenecks/b-negative-results/"},{"id":"b-misinformation","kind":"bottleneck","name":"Misinformation and unproven therapies","route":"/bottlenecks/b-misinformation/"}],"paper":[{"id":"paper-manson-n-engl-j-med","kind":"paper","name":"Vitamin D Supplements and Prevention of Cancer and Cardiovascular Disease","route":"/key-papers/paper-manson-n-engl-j-med/"}],"roadmap":[{"id":"nutrition-lifestyle-roadmap","kind":"roadmap","name":"Diet, exercise and lifestyle roadmap: causes established → interventions that disappointed → exercise proven as treatment","route":"/roadmaps/nutrition-lifestyle-roadmap/"}]}}