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Vitamin

Vitamin D2 (Ergocalciferol)

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Vitamin D2 (Ergocalciferol). Plant-derived prescription D — high doses (50,000 IU) used for rapid deficiency correction.

How it works. Same VDR endpoint as D3, but ~30% less effective at raising 25(OH)D per unit.

What the research supports. 1 graded claims. Strongest: Corrects deficiency at high prescription dose (strong).

How much to take. Typical dose: 50,000 IU weekly × 8 wk (Rx).

Side effects and interactions. 1 medication interaction listed. Serious: Hypercalcemia (acute high-dose).

Stacking. Pairs well with A high-quality multivitamin, Omega-3 (EPA/DHA).

Common forms. Available as Capsule or softgel, Sublingual tablet or liquid, Methylated active form for sensitive individuals, Multivitamin matrix.

Key studies. 8 studies cited. The strongest are listed with links to PubMed.

Community. Experiences from people who have tried Vitamin D2 (Ergocalciferol). Anecdotes are not medical advice.

Vitamin D2 (Ergocalciferol). Plant-derived prescription D — high doses (50,000 IU) used for rapid deficiency correction.

Molecular structureC28H44O · 396.6 g/mol

What it is

Plant-derived prescription D — high doses (50,000 IU) used for rapid deficiency correction.

Food sources

Whole-food sources (animal products for fat-soluble and B-complex vitamins; produce for water-soluble vitamins)Fortified foods (cereals, dairy, plant milks, nutritional yeast)Multivitamins or stand-alone supplements in synthetic or food-derived form

Goals

Bone HealthGeneral Wellness

How it works

Same VDR endpoint as D3, but ~30% less effective at raising 25(OH)D per unit.

Pathways

  • Same VDR endpoint as D3, but ~30% less effective at raising 25(OH)D per unit

Effects

  • +Corrects deficiency at high prescription dose supports

What the research supports

Corrects deficiency at high prescription dosestrong

Strong: consistent results across large trials or meta-analyses. Moderate: several trials, mostly positive. Limited: small or mixed studies. Preclinical: animal or cell research only.

Typical dose
50,000 IU weekly × 8 wk (Rx)
TimingConsistent daily timing recommended; split larger doses if GI tolerance is a concern.
With foodWith fat
Best formMost evidence is based on the capsule or softgel form.
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Side effects & interactions

Serious

  • Hypercalcemia (acute high-dose)

Medication interactions

Prescription medications (general)minor

Always disclose Vitamin D2 (Ergocalciferol) use to your prescriber — additive, antagonistic, or pharmacokinetic interactions are possible.

Check any supplement–medication combination with your pharmacist before starting.

Combines with

Pairs well

  • A high-quality multivitaminCovers micronutrient cofactors that support most supplement pathways.
  • Omega-3 (EPA/DHA)Foundational anti-inflammatory support that complements most regimens.

Common forms

  • Capsule or softgel
  • Sublingual tablet or liquid
  • Methylated active form for sensitive individuals
  • Multivitamin matrix

Key studies

8 studies cited in total.

Vitamin D3 vs D2 in raising 25(OH)D ↗
Meta-analysis · Am J Clin Nutr · 2012

D2 raises 25(OH)D less than D3 at equivalent doses.

PubMed: Vitamin D2 (Ergocalciferol) — Corrects deficiency at high prescription dose ↗
Systematic review · PubMed (NLM) · 2026

Opens current human and preclinical literature matching Vitamin D2 (Ergocalciferol) and "Corrects deficiency at high prescription dose". Filter by RCT, meta-analysis, or year on the results page.

PubMed: Vitamin D2 (Ergocalciferol) — randomized controlled trial ↗
Systematic review · PubMed (NLM) · 2026

Opens current human and preclinical literature matching Vitamin D2 (Ergocalciferol) and "randomized controlled trial". Filter by RCT, meta-analysis, or year on the results page.

Discussion

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