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DOSERANKEVIDENCE-BASED SUPPLEMENTSFull analysis

The short answer · Respiratory infection incidence

Take vitamin d3 (cholecalciferol) for respiratory infection incidence. This is the one to buy.

Micro Ingredients, Vitamin D3 + K2, 300 Softgels
1

Micro Ingredients, Vitamin D3 + K2, 300 Softgels

4.9· 2,205 ratings· $0.10/serving

DoseRank score87

Vitamin D3 (Cholecalciferol) 5000 IU — higher than the studied 400-4000 IU window

Of 5,717 products scored for Respiratory infection incidence, Micro Ingredients, Vitamin D3 + K2, 300 Softgels ranks #1 with a DoseRank score of 87. Vitamin D3 (Cholecalciferol) is the strongest evidence signal for this outcome.

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The form“Why Vitamin D3 (Cholecalciferol) — not Vitamin D or Lacticaseibacillus rhamnosus?”Evidence Strong evidence

Vitamin D3 (Cholecalciferol) is the strongest evidence signal for this outcome.

  • Vitamin D3 (Cholecalciferol)The pick

    Strong evidence · 5000 IU

    The form made by skin on sun exposure and used in most supplements; converts to active calcitriol and raises serum 25(OH)D more effectively than D2.

  • Vitamin D

    Strong evidence · 5000 IU

    Fat-soluble vitamin made in skin from sunlight; needed for calcium absorption, bone health, and immune modulation, and widely deficient in low-sun regions.

  • Lacticaseibacillus rhamnosus

    Moderate evidence · 2000000000 CFU

    Widely studied probiotic species; the GG strain has evidence for preventing antibiotic-associated diarrhea and supporting gut barrier integrity.

Buy the #1 pick

Questions

Frequently asked

Micro Ingredients, Vitamin D3 + K2, 300 Softgels ranks #1 for Respiratory infection incidence with a DoseRank score of 87. The score blends clinical strength, evidence, dose fit, trust signals and value across 5,717 products scored for this outcome.

Vitamin D3 (Cholecalciferol) is the strongest evidence signal for this outcome.

Vitamin D3 (Cholecalciferol) at 5000 IU is higher than the studied 400-4000 IU window. DoseRank scores this product's dose fit at 91 out of 100.

Micro Ingredients, Vitamin D3 + K2, 300 Softgels works out at $0.10 per serving. $0.10 per serving — low price tier for this outcome. The cheapest ranked pick here is $0.08 per serving.

No. Retailer links may be affiliate links, but rankings and placement are never paid. Every product is scored by the same public model, and the ranking is recomputed from the underlying product data rather than edited by hand.

Keep exploring

Other outcomes

  • Gastrointestinal infection incidenceFrequency of infectious GI illnesses.
  • Infection incidenceOverall rate of infectious illness.

Use rankings as research support

DoseRank rankings are informational and not medical advice. If you are pregnant, breastfeeding, using medications, or managing a health condition, ask a qualified clinician whether a supplement fits your situation. Stop use and report concerning adverse events to a clinician, the product maker, or the retailer.

Disclosure

Retailer links may be affiliate links. Rankings and placement are not paid placement.

Micro Ingredients, Vitamin D3 + K2, 300 Softgels

$0.10/serving · ★ 4.9 · In stock

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— $0.10/sv
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Cheaper alternative$0.08 per servingChildLife Essentials, Vitamin D3, Natural Berry, 12.5 mcg (500 IU), 1 fl oz (30 ml)

Retailer links may be affiliate links. Rankings and placement are never paid.

The dose“Is the dose actually effective?”Dose fit 91

Vitamin D3 (Cholecalciferol) at 5000 IU is higher than the studied 400-4000 IU window.

Vitamin D3 (Cholecalciferol)

Studied window 400-4000 IU · this pick 5000 IU

100 mcg
The ranking“Why should I trust this pick?”Trust 88

Strong trust signals — consistently high marks from verified buyer ratings. Each product gets a DoseRank score blending clinical strength, evidence, dose fit, trust and value. Retailer links may be affiliate links — the scoring model decides placement, never payment from a brand.

  • 5,717 products scored
  • Never paid placement
  • Evidence level: Strong · 92
  • 504 brands
  • 15 ingredients
See the full analysis — every score, every productHow the ranking works
The price“Can I do better than $0.10 a serving?”Value 84

$0.10 per serving — low price tier for this outcome. The cheapest ranked pick here is $0.08 per serving.

  • 2
    ChildLife Essentials, Vitamin D3, Natural Berry, 12.5 mcg (500 IU), 1 fl oz (30 ml)Score 85 · $0.08/serving
    iHerb

Why not the absolute cheapest? The DoseRank score also weighs clinical strength, evidence, dose fit and trust — the very cheapest listings rarely hold up everywhere else.

Ready?

The #1 pick is $0.10 a serving.

Micro Ingredients, Vitamin D3 + K2, 300 Softgels — in stock at a tracked retailer.

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