Vitamin D2
Vitamin ·Exploratory record · not publication-reviewed ·Updated July 13, 2026
Plant-derived form of vitamin D, less potent than D3 but suitable for vegans.
Exploratory record, not a reviewed medical publication.
See the editorial and medical-review policies for the publication gate.
This generated database record has not completed a claim-level review by a qualified human medical reviewer. Bibliography links and evidence labels are not approval. The page remains available for reference and is excluded from search indexing.
What the research says.
A quick, data-only summary. The full evidence, dosing, and sources are below.
Vitamin D2 is a vitamin most often used for bone health, immune support, vegan-friendly d source. NutriStack rates the overall evidence as moderate. A typical adult dose is 1,000-2,000 IU daily, commonly taken as ergocalciferol from uv-irradiated mushrooms. This profile indexes 16 sources.
The bottom line
Evidence rating moderate. Most-documented uses: bone health, immune support, vegan-friendly d source. 16 sources indexed (2006–2024), with 0 interaction records on file.
How it works, mechanistically.
Core mechanism
Converted to 25-hydroxyvitamin D2 in the liver. Less efficiently raises serum 25(OH)D levels compared to D3.1,8
Dosing & protocol.
What it actually costs.
Real-world pricing across three quality tiers. Assumes Ergocalciferol.
Assumes 1,000-2,000 IU/day. Vendor basis: iHerb, Vitacost, Amazon marketplace, and specialty vegan D2 products; D2 is less commonly stocked than D3. Updated 2026-05-28.
The same dose, as food.
How much you'd eat to match a supplemental dose.
Vitamin D2 content depends heavily on UV exposure and fortification level.
Full safety detail.
Sources, by evidence tier.
Numbered references. Citations throughout the page link here.
Meta-analyses & systematic reviews
3- 1Comparison of the Effect of Daily Vitamin D2 and Vitamin D3 Supplementation on Serum 25-Hydroxyvitamin D Concentration (Total 25(OH)D, 25(OH)D2, and 25(OH)D3) and Importance of Body Mass Index: A Systematic Review and Meta-AnalysisPMIDItkonen ST et al. · Adv Nutr · 2023
Average daily dose was the single significant predictor of effect size difference between D2 and D3, with BMI potentially moderating absorption.
- 2Relative Efficacy of Vitamin D2 and Vitamin D3 in Improving Vitamin D Status: Systematic Review and Meta-AnalysisPMIDBalachandar R et al. · Am J Clin Nutr · 2021
Meta-analysis of 1,277 participants from 24 studies found cholecalciferol (D3) raised total 25(OH)D 15.69 nmol/L higher than ergocalciferol (D2), with smaller differences at lower doses.
- 3Model-based meta-analysis for comparing Vitamin D2 and D3 parent-metabolite pharmacokineticsPMIDOcampo-Pelland AS, Gastonguay MR, Riggs MM · Journal of pharmacokinetics and pharmacodynamics · 2017
Ocampo-Pelland AS, Gastonguay MR, Riggs MM. Model-based meta-analysis for comparing Vitamin D2 and D3 parent-metabolite pharmacokinetics. Journal of pharmacokinetics and pharmacodynamics. 2017
Randomized controlled trials
5- 4Vitamins D2 and D3 Have Overlapping But Different Effects on the Human Immune System Revealed Through Analysis of the Blood TranscriptomePMIDDurrant LR et al. · Front Immunol · 2022
D2 and D3 share structural similarity but functional equivalence in vitamin D-dependent effects on human physiology has not been well defined; transcriptomic analysis reveals different immune modulation.
- 5Ergocalciferol in New-onset Type 1 Diabetes: A Randomized Controlled TrialPMIDNwosu BU, Parajuli S, Jasmin G et al. · Journal of the Endocrine Society · 2022
Nwosu BU, Parajuli S, Jasmin G et al.. Ergocalciferol in New-onset Type 1 Diabetes: A Randomized Controlled Trial. Journal of the Endocrine Society. 2022
- 6Ergocalciferol Supplementation in Hemodialysis Patients With Vitamin D Deficiency: A Randomized Clinical TrialPMIDMiskulin DC, Majchrzak K, Tighiouart H et al. · Journal of the American Society of Nephrology : JASN · 2016
Miskulin DC, Majchrzak K, Tighiouart H et al.. Ergocalciferol Supplementation in Hemodialysis Patients With Vitamin D Deficiency: A Randomized Clinical Trial. Journal of the American Society of Nephrology : JASN. 2016
- 7Ergocalciferol supplementation in children with CKD delays the onset of secondary hyperparathyroidism: a randomized trialPMIDShroff R, Wan M, Gullett A et al. · Clinical journal of the American Society of Nephrology : CJASN · 2012
Shroff R, Wan M, Gullett A et al.. Ergocalciferol supplementation in children with CKD delays the onset of secondary hyperparathyroidism: a randomized trial. Clinical journal of the American Society of Nephrology : CJASN. 2012
- 8Vitamin D2 is much less effective than vitamin D3 in humansSource linkedPMIDHeaney RP, Recker RR, Grote J et al. · J Clin Endocrinol Metab · 2011
Reviews & position papers
7- 9Clinical Efficacy and Mechanism of Vitamin D2 in Treating Hashimoto's ThyroiditisPMIDGan L, Li Y · Journal of inflammation research · 2024
Gan L, Li Y. Clinical Efficacy and Mechanism of Vitamin D2 in Treating Hashimoto's Thyroiditis. Journal of inflammation research. 2024
- 10Efficacy of plain cholecalciferol versus ergocalciferol in raising serum vitamin D level in Thai female healthcare workersPMIDAmphansap T, Therdyothin A, Stitkitti N et al. · Osteoporosis and sarcopenia · 2022
Amphansap T, Therdyothin A, Stitkitti N et al.. Efficacy of plain cholecalciferol versus ergocalciferol in raising serum vitamin D level in Thai female healthcare workers. Osteoporosis and sarcopenia. 2022
- 11Immunologic Effects of Vitamin D on Human Health and DiseasePMIDCharoenngam N et al. · Nutrients · 2020
Active vitamin D generates immunologic activities on innate and adaptive immune systems; deficiency associated with increased autoimmunity and susceptibility to infection.
- 12Treatment Effect of Ergocalciferol on Bone Metabolism Indexes and Parathyroid Hormone in Hemodialysis PatientsPMIDBashardoust B, Zakeri A, Fouladi N et al. · Iranian journal of kidney diseases · 2018
Bashardoust B, Zakeri A, Fouladi N et al.. Treatment Effect of Ergocalciferol on Bone Metabolism Indexes and Parathyroid Hormone in Hemodialysis Patients. Iranian journal of kidney diseases. 2018
- 13Comparative efficacy and safety of different doses of ergocalciferol supplementation in patients with metabolic syndromePMIDSansanayudh N, Wongwiwatthananukit S, Phetkrajaysang N et al. · International journal of clinical pharmacy · 2014
Sansanayudh N, Wongwiwatthananukit S, Phetkrajaysang N et al.. Comparative efficacy and safety of different doses of ergocalciferol supplementation in patients with metabolic syndrome. International journal of clinical pharmacy. 2014
- 14The lack of vitamin D toxicity with megadose of daily ergocalciferol (D2) therapy: a case report and literature reviewPMIDStephenson DW, Peiris AN · Southern medical journal · 2009
Stephenson DW, Peiris AN. The lack of vitamin D toxicity with megadose of daily ergocalciferol (D2) therapy: a case report and literature review. Southern medical journal. 2009
- 15The case against ergocalciferol (vitamin D2) as a vitamin supplementPMIDHoughton LA et al. · Am J Clin Nutr · 2006
Vitamin D2 has shorter plasma half-life, lower affinity for vitamin D binding protein, hepatic hydroxylase and VDR; should not be regarded as equivalent to vitamin D3.
Common questions.
Quick answers about Vitamin D2, drawn from the data on this page.
What is Vitamin D2?
Plant-derived form of vitamin D, less potent than D3 but suitable for vegans.
What is Vitamin D2 used for?
Commonly cited benefits of Vitamin D2 include: Bone health; Immune support; Vegan-friendly D source. NutriStack rates the overall evidence as moderate.
What is a typical dose of Vitamin D2?
A typical adult dose of Vitamin D2 is 1,000-2,000 IU daily. The commonly recommended form is Ergocalciferol from UV-irradiated mushrooms. These are general ranges, not personalized advice; confirm the right dose with a clinician.
What are the side effects of Vitamin D2?
Reported side effects include generally well-tolerated, less effective than d3 at raising levels. This is educational information; check with a healthcare professional before use.
How strong is the evidence for Vitamin D2?
NutriStack rates this as Moderate, meaning several aligned RCTs or one large RCT plus supporting reviews. Full tier criteria are at https://nutristackapp.com/methodology/evidence-tiers.
Use this with your stack
Vitamin D2 in NutriStack.
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