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evidence · mechanism · dose
Supplements/Vitamin

Vitamin C (Immune Use)

High-dose vit C at symptom onset — modestly shortens cold duration.

Immune Function (alias)Infection SupportSeasonal WellnessAntioxidants

Overview

High-dose vit C at symptom onset — modestly shortens cold duration.

Natural sources
    Common forms

      Mechanism of action

      Concentrated in neutrophils; antioxidant during respiratory burst.

      Pathways

        Effects on the body

        Organ system effects

        Evidence-based benefits

        Shortens cold duration ~8% adults, ~14% kids

        Moderate evidence

        Potential side effects

        Common
        • · Loose stools
        Rare
          Serious

            Drug interactions

            No notable interactions reported.

            Supplement interactions

            Pairs well with

            None listed.

            Avoid combining with

            No specific avoidances listed.

            Dosing & bioavailability

            Typical dose
            1000 mg q4h at symptom onset
            With food?
            Optional

            Where to buy

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            Thorne
            Practitioner-grade · NSF tested

            Scientific evidence (8)

            Meta-analysisCochrane Database · 2013

            Vitamin C for preventing and treating the common cold

            Hemilä H, Chalker E

            Cochrane review of 29 trials.

            Key findings

            Modest reduction in cold duration and severity.

            Open study
            Systematic reviewPubMed (NLM) · 1970

            PubMed: Vitamin C (Immune Use) — Shortens cold duration ~8% adults, ~14% kids

            Live PubMed search

            Live results for "Vitamin C (Immune Use) Shortens cold duration ~8% adults, ~14% kids" across the PubMed/MEDLINE peer-reviewed index.

            Key findings

            Opens current human and preclinical literature matching Vitamin C (Immune Use) and "Shortens cold duration ~8% adults, ~14% kids". Filter by RCT, meta-analysis, or year on the results page.

            Open study
            Systematic reviewPubMed (NLM) · 1970

            PubMed: Vitamin C (Immune Use) — randomized controlled trial

            Live PubMed search

            Live results for "Vitamin C (Immune Use) randomized controlled trial" across the PubMed/MEDLINE peer-reviewed index.

            Key findings

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

            Open study
            Systematic reviewPubMed (NLM) · 1970

            PubMed: Vitamin C (Immune Use) — meta-analysis

            Live PubMed search

            Live results for "Vitamin C (Immune Use) meta-analysis" across the PubMed/MEDLINE peer-reviewed index.

            Key findings

            Opens current human and preclinical literature matching Vitamin C (Immune Use) and "meta-analysis". Filter by RCT, meta-analysis, or year on the results page.

            Open study
            Systematic reviewPubMed (NLM) · 1970

            PubMed: Vitamin C (Immune Use) — pharmacokinetics

            Live PubMed search

            Live results for "Vitamin C (Immune Use) pharmacokinetics" across the PubMed/MEDLINE peer-reviewed index.

            Key findings

            Opens current human and preclinical literature matching Vitamin C (Immune Use) and "pharmacokinetics". Filter by RCT, meta-analysis, or year on the results page.

            Open study
            Systematic reviewPubMed (NLM) · 1970

            PubMed: Vitamin C (Immune Use) — safety adverse events

            Live PubMed search

            Live results for "Vitamin C (Immune Use) safety adverse events" across the PubMed/MEDLINE peer-reviewed index.

            Key findings

            Opens current human and preclinical literature matching Vitamin C (Immune Use) and "safety adverse events". Filter by RCT, meta-analysis, or year on the results page.

            Open study
            Systematic reviewPubMed (NLM) · 1970

            PubMed: Vitamin C (Immune Use) — dose response

            Live PubMed search

            Live results for "Vitamin C (Immune Use) dose response" across the PubMed/MEDLINE peer-reviewed index.

            Key findings

            Opens current human and preclinical literature matching Vitamin C (Immune Use) and "dose response". Filter by RCT, meta-analysis, or year on the results page.

            Open study
            Systematic reviewGoogle Scholar · 1970

            Google Scholar: Vitamin C (Immune Use) — clinical evidence

            Live Scholar search

            Cross-database citation index for Vitamin C (Immune Use) as it relates to "clinical evidence".

            Key findings

            Includes preprints, theses, and journal articles. Useful for tracking citation counts and follow-on work.

            Open study
            Educational use only. This profile is not medical advice. Consult a qualified healthcare professional before starting any supplement, especially if you take prescription medication or have a chronic condition.