Key findings from detailed records
Population: 25,871 participants: men aged 50 or older and women aged 55 or older Findings: Cancer: HR 0.96 (95% CI 0.88–1.06); major cardiovascular events: HR 0.97 (0.85–1.12). Neither was significantly reduced.
KNOWLEDGE RECORD
- Category
- Vitamins and minerals
- Last Reviewed
Names and related search termsVitamin D / Vitamin D / Cholecalciferol / D3
Study type: human intervention study.
OUTCOME-SPECIFIC EVIDENCE
Scientific Evidence Profile
Assessment pending
An outcome-specific assessment has not yet been completed. This is not a finding that the ingredient is ineffective. The study records below remain available.
This profile concerns the stated outcome and population, not the ingredient as a whole. It is not a probability of benefit, a safety rating, a product efficacy rating or an indication of product adoption.
How we assess evidenceIngredient Profile
- What is it, and where is it found?
- Vitamin D is fat-soluble. D2 and D3 are different forms; dietary intake and skin synthesis both contribute to vitamin D status. [1]
Sources for this profile
Compound properties and formulation properties are different. These sources do not establish the efficacy of a finished supplement.
- NIH Office of Dietary Supplements — VitaminD Nutrient identity and food-source reference. Published by NIH Office of Dietary Supplements. Reference synthesis; not an individual clinical trial.
Profile sources checked:
Read the evidence in context
- Evidence: what was measured in the stated population or experimental model.
- Inference: an interpretation connecting findings; its applicability depends on the study conditions.
- Hypothesis: a proposed explanation or effect that remains to be tested.
Why It Matters #
Is correcting a deficiency the same as preventing disease in a general population? Check the detailed records for study conditions and use the literature map to compare other populations and outcomes.
What Was Studied #
25,871 participants: men aged 50 or older and women aged 55 or older VITAL: Randomized, double-blind, placebo-controlled trial. Outcomes: Invasive cancer and major cardiovascular events[1]
What Was Found #
Cancer: HR 0.96 (95% CI 0.88–1.06); major cardiovascular events: HR 0.97 (0.85–1.12). Neither was significantly reduced.[1]
What the Evidence Means #
The trial did not test treatment of deficiency and does not answer every question about bone health.[1]
Comparing similar populations, formulations, durations and outcomes helps identify where findings agree and where they differ.
What We Can Learn #
Distinguish nutritional requirements from the benefits of extra supplementation in people with adequate status.
What Remains Unknown #
Further questions include reproducibility across populations and formulations, and the long-term balance of benefits and harms. Use the literature map as a starting point for these questions.
LITERATURE MAP / 10 PAPERS
Compare papers by conditions and findings.
A literature map covering different populations, outcomes and formulations. Read alongside detailed records to avoid treating one trial as the conclusion for an entire ingredient.
Selected: 2026-09-21. Bibliographic information checked against Europe PMC / PubMed. Editorial selection considered major papers and a range of populations and questions. This is not a systematic search covering all recent research.
10 RECORDS
A dash marks fields outside the bibliographic record. Use detailed records to compare findings and design records to connect mechanisms.
No papers match. Change the search conditions.
The literature map is an index of research questions and references. Individual assessment of results, doses, funding and COI is limited to the detailed study records. Related reports from the same trial may be included; paper counts are not counts of independent trials.
Explore the research Study Records
Listed doses describe study conditions, not recommended intake.
Vitamin D Supplements and Prevention of Cancer and Cardiovascular Disease.
PubMed 30415629DOI: 10.1056/nejmoa1809944
- Authors
- Manson JE, Cook NR, Lee IM, Christen W, Bassuk SS, Mora S, Gibson H, Gordon D, Copeland T, D'Agostino D, Friedenberg G, Ridge C, Bubes V, Giovannucci EL, Willett WC, Buring JE, VITAL Research Group.
- Journal
- The New England journal of medicine
- Publication year
- 2019
- Study design
- VITAL: Randomized, double-blind, placebo-controlled trial
- Participants
- 25,871 participants: men aged 50 or older and women aged 55 or older
- Dose and intervention
- Vitamin D3 2,000 IU/day
- Duration
- Median 5.3 years
- Outcomes and their role in the study
- Invasive cancer and major cardiovascular events
- Findings
- Cancer: HR 0.96 (95% CI 0.88–1.06); major cardiovascular events: HR 0.97 (0.85–1.12). Neither was significantly reduced.
- Limitations
- The trial did not test treatment of deficiency and does not answer every question about bone health.
- Funding
- NIH funded VITAL. Pharmavite supplied vitamin D and Pronova BioPharma/BASF supplied fish oil and matching placebos; Quest Diagnostics provided assays. NIH collaborated in design, conduct and interpretation; final decisions remained with the investigators.
- Conflict of Interest
- The available author manuscript states that all authors submitted ICMJE disclosure forms. The individual forms were not reviewed here; this is not a statement that no conflicts existed. Study funding and donated products are identified above.
- Scope of source review
- Relevant methods, results, safety and funding in the primary author manuscript checked on 2026-10-24. Individual ICMJE forms remain unchecked.
Cite this page
LÍFSVARÐA. Vitamin D: Is correcting a deficiency the same as preventing disease in a general population? Version 1.1 / Updated 2026-10-24
https://lifsvarda.com/knowledge/vitamin-d/Edited by LÍFSVARÐA (product brand).Editorial policy
Safety and interactions
Count vitamin D from all supplements. Excess intake can cause high blood calcium and kidney injury. Kidney impairment, hyperparathyroidism or thiazide use warrants clinical advice before supplementation. Deficiency treatment may require individualized dosing and monitoring; a trial dose is not a universal daily recommendation.
Safety section reviewed: 2026-10-24.
Sources and updates
- Manson JE, Cook NR, Lee IM, Christen W, Bassuk SS, Mora S, Gibson H, Gordon D, Copeland T, D'Agostino D, Friedenberg G, Ridge C, Bubes V, Giovannucci EL, Willett WC, Buring JE, VITAL Research Group. (2019). Vitamin D Supplements and Prevention of Cancer and Cardiovascular Disease.Relevant methods, results, safety and funding in the primary author manuscript checked on 2026-10-24. Individual ICMJE forms remain unchecked.
First published: 2026-09-21 / Version 1.1. Updated 2026-09-23: Added a research comparison table and links to design records. Source notes identify the scope of verification when the full paper has not been reviewed. Research summaries and LÍFSVARÐA’s interpretation are distinguished.