Vitamin D3Evidence & Dosage
Bones, immune system, hormones — optimal levels, deficiency symptoms, and dosage studies.
Evidence at a glance
- Total studies
- 1,000
- With abstract
- 46
- Meta / Systematic / RCT
- 119
- Highly cited
- 6
- Publication years
- 1975–2026
Vitamin D3 in the context of Vitamins & Minerals
This topic is part of our "Vitamins & Minerals" world. There you'll find methodology, evidence and the highest-impact levers — plus the order in which they sensibly build on each other.
Go to Vitamins & MineralsTop studies on Vitamin D3
Ranked by influential-citation count and publication year.
Comparison of vitamin D2 and vitamin D3 supplementation in raising serum 25-hydroxyvitamin D status: a systematic review and meta-analysis.
Am J Clin Nutr2012n=1,016meta200 influential citationsBACKGROUND: Currently, there is a lack of clarity in the literature as to whether there is a definitive difference between the effects of vitamins D2 and D3 in the raising of serum 25-hydroxyvitamin D [25(OH)D]. OBJECTIVE: The objective of…
Finding: This systematic review and meta-analysis found that vitamin D3 supplementation raised serum 25(OH)D concentrations more than vitamin D2 overall.
A systematic review of evidence-based clinical guidelines for vitamin D screening and supplementation over the last decade.
Arch Public Health2025n=31Systematic Review28 influential citations<h4>Background</h4>Amid growing evidence from observational data and trials with various results on the association between vitamin D and multiple diseases, numerous clinical guidelines were generated [1, 2]. The aims of this systematic…
Vitamin D supplementation in the prevention and management of major chronic diseases not related to mineral homeostasis in adults: research for evidence and a scientific statement from the European society for clinical and economic aspects of osteoporosis and osteoarthritis (ESCEO).
Endocrine2017n=76,00024 influential citations<h4>Introduction</h4>Optimal vitamin D status promotes skeletal health and is recommended with specific treatment in individuals at high risk for fragility fractures. A growing body of literature has provided indirect and some direct…
Effectiveness of Vitamin D Supplementation on Biochemical, Clinical, and Inflammatory Parameters in Patients with Different Types of Diabetes: A Systematic Review and Meta-Analysis.
Nutrients2025n=14,831Meta-Analysis22 influential citations<b>Background and Aims:</b> Numerous clinical and observational studies have examined the role of vitamin D in glycemic control and metabolic regulation among diabetic patients, but findings remain inconsistent. This meta-analysis aimed to…
Finding: Vitamin D supplementation significantly reduced HbA1c% in the meta-analysis.
The causal effect of vitamin D binding protein (DBP) levels on calcemic and cardiometabolic diseases: a Mendelian randomization study.
PLoS medicine2014n=46,18619 influential citations<h4>Background</h4>Observational studies have shown that vitamin D binding protein (DBP) levels, a key determinant of 25-hydroxy-vitamin D (25OHD) levels, and 25OHD levels themselves both associate with risk of disease. If 25OHD levels…
The Effect of Genistein Supplementation on Vitamin D Levels and Bone Turnover Markers during the Summer in Healthy Postmenopausal Women: Role of Genotypes of Isoflavone Metabolism.
J Nutrigenet Nutrigenomics2017n=102RCT6 influential citations<b><i>Aims:</i></b> The objective of this study was to determine whether vitamin D and genistein supplementation had an additive beneficial effect on levels of vitamin D and bone markers and whether this effect was mediated by genes…
Higher serum vitamin D concentration and supplementation were associated with improved survival outcomes and treatment response in cancer patients receiving immunotherapy: A systematic review and meta-analysis.
Nutr Res2025n=259Meta-Analysis4 influential citationsBiological evidence has demonstrated the anti-tumor effects of vitamin D, but whether it could predict the effect of cancer immunotherapy remains inconclusive. We hypothesized that higher serum vitamin D concentration and supplementation…
Finding: Vitamin D supplementation was associated with prolonged overall survival in cancer patients receiving immunotherapy.
The effects of magnesium and vitamin D/E co-supplementation on inflammation markers and lipid metabolism of obese/overweight population: a systematic review and meta-analysis.
Front Nutr2025n=509Systematic Review4 influential citations<h4>Background</h4>Inflammatory reactions can induce or facilitate the occurrence and development of various diseases in the human body. It is crucial to regulate and actively control inflammatory factors to maintain the health of an…
Association of vitamin D with risk of dementia: a dose-response meta-analysis of observational studies.
Front Neurol2025n=53,122Systematic Review3 influential citations<h4>Background</h4>The relationship between serum vitamin D levels and dementia risk remains unclear. This meta-analysis aims to evaluate the association and dose-response relationship between vitamin D levels and dementia…
Is Vitamin D Fortification of Dairy Products Effective for Improving Vitamin D Status? A Systematic Review and Meta-Analysis of Randomised Controlled Trials.
Nutrients2025n=496Meta-Analysis2 influential citations<b>Background/objectives</b>: Given the suboptimal vitamin D intake and status among the United Kingdom population, the Scientific Advisory Committee on Nutrition is seeking suitable food vehicles for vitamin D fortification. Thus, this…
Frequently asked
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Related articles
Which supplement best supports self-optimization?
If you can only choose one: vitamin D3 2000-4000 IU/day — 40-80 % of Central Europeans have suboptimal 25(OH)D levels, supplementation is cheap, safe, and corrects a common deficit. For other goals: creatine (strength+cognition), omega-3 (in elevated triglycerides), magnesium bisglycinate (sleep). 'Best' depends on the deficit, not on marketing.
Vitamin K2 (MK-7): Dosage, D3 Synergy, and the Evidence Base
Vitamin K2 (MK-7) is mainly relevant for bone; the data on blood vessels are mixed. Here, dosage, MK-7 vs. MK-4, and D3 combination are classified clearly.
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