Scientific consensus contradicts this claim.

Not medical advice — just what the research says.

What's still open

What the evidence found 3 findings
Based on 13 sources:
PMC peer-reviewed View
PMC peer-reviewed View
Nature peer-reviewed View
Sage Journals peer-reviewed View
PMC peer-reviewed View
Clinical Nutrition Journal peer-reviewed View
PMC article on VITAL study 25-hydroxyvitamin D levels peer-reviewed View
VITAL Study official guidelines institutional View
PMC peer-reviewed View
JAMA Cardiology peer-reviewed View
The Optimal Protective 25-Hydroxyvitamin D Level for Different Conditions peer-reviewed View
Guidelines for Preventing and Treating Vitamin D Deficiency peer-reviewed View
Recommended intakes of vitamin D to optimise health peer-reviewed View
Based on 12 sources:
PMC peer-reviewed View
Harvard Health institutional View
Mayo Clinic institutional View
PMC peer-reviewed View
NIH Office of Dietary Supplements institutional View
ResearchGate peer-reviewed View
NCBI peer-reviewed View
A Zittermann et al., 2023 peer-reviewed View
Z Malihi et al., 2016 peer-reviewed View
PMC Article peer-reviewed View
PMC Article peer-reviewed View
ResearchGate Publication peer-reviewed View
Based on 14 sources:
PMC - NIH Systematic Review peer-reviewed View
ScienceDirect peer-reviewed View
PMC peer-reviewed View
PMC peer-reviewed View
PMC peer-reviewed View
MDPI peer-reviewed View
Science Direct peer-reviewed View
Linus Pauling Institute, Oregon State University institutional View
PMC systematic review and meta-analysis peer-reviewed View
MDPI Nutrients journal peer-reviewed View
Examine.com research database institutional View
PMC Article on Vitamin D in Critical Care peer-reviewed View
PMC Meta-Analysis on Vitamin D in Critical Care peer-reviewed View
Frontiers in Nutrition peer-reviewed View
What research hasn't answered 3 gaps
PMC peer-reviewed View
Harvard Health institutional View
Mayo Clinic institutional View
PMC peer-reviewed View
NIH Office of Dietary Supplements institutional View
PMC peer-reviewed View
PMC peer-reviewed View
Nature peer-reviewed View
Sage Journals peer-reviewed View
PMC peer-reviewed View
PMC peer-reviewed View
PMC peer-reviewed View
Nature peer-reviewed View
Sage Journals peer-reviewed View
PMC peer-reviewed View
Sources 20 findings
argumentation Unknown
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tree-leaf argumentation
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2019 tree-leaf argumentation
tree-leaf argumentation
tree-leaf argumentation
tree-leaf argumentation
tree-leaf argumentation
tree-leaf argumentation
argumentation Unknown
argumentation Unknown
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Generated by reaso.ai's editorial pipeline: claim restated, scientific consensus classified via 3-run majority vote, 20 findings enriched with attribution and study type, narrative written in neutral voice. No individual researcher has signed off on this specific analysis — see methodology for how the pipeline works. Built with Claude Sonnet by Anthropic. Updated April 16, 2026. How we do this →

Written by AI. Sources are linked for verification.