Supplement evidence

008 / 575Mineral

Zinc

View my plan →

The short answer

Preventing or treating zinc deficiency; some lozenge protocols may shorten a cold when started early.

Evidence and scope: Established for an indicated use
This status does not grade the ingredient for every goal, outcome, or person.
Important limitation: Routine high-dose use has not been shown to extend life or prevent ordinary infections.
Before deciding: Long-term high doses can cause copper deficiency and neurologic problems.

01 / PRACTICAL GUIDE

Dose, absorption, and combinations

These are indication-specific reference or studied ranges—not a personalized prescription. Start with the objective, then check the form, label, medicines, and health conditions.

Reference range by objective

Meeting usual needs8 mg/day women; 11 mg/day men from all sources

Reference or studied range—not a personalized prescription. The product label or a clinician may specify a different dose.

Dose source ↗

Respiratory researchCold-lozenge studies often exceed normal needs for a few days; not for chronic use

Reference or studied range—not a personalized prescription. The product label or a clinician may specify a different dose.

Dose source ↗

More is not automatically better. A clinician or product label may specify a different amount.

Absorption / solubilityWater-soluble

Water-soluble or readily water-dispersible. This does not mean excess is always harmless.

How it is commonly taken

Food reduces nausea, but high-phytate meals reduce absorption.

Do not combine casually

Separate from tetracycline/quinolone antibiotics; chronic high doses can cause copper deficiency.

Dose and use source ↗

Dose and use links lead to primary or official source material. Search links are discovery tools, not proof that every returned paper applies.

02 / EVIDENCE

What the research says

We keep supportive, mixed, negative, safety, and contextual findings together. The headline never replaces the underlying papers.

5research papers in this ledger

35unique primary studies represented

8,557unique participants represented

These are audited counts for this JIVANA collection, not search-result totals. Participants are counted once when multiple papers use the same cohort; review papers are not added again to participant totals.

Open the research timelineResearch timeline

Entries are ordered by publication year. A study period appears only when the source reports it.

2024

Mixed or qualifiedPMID 38719213

Zinc for prevention and treatment of the common cold

Zinc probably does little for prevention and may shorten an ongoing cold by about 2.4 days, but certainty was low and non-serious adverse events increased.

Published: 2024n=8,526 participants34 primary studies represented

Study design and methods

Design: Cochrane systematic review of randomized trials
Population: 8,526 children and adults across 34 studies
Intervention: Multiple zinc formulations and routes versus placebo
Outcome: Cold prevention, duration, symptoms, and adverse events

Funding or conflict note: The review authors reported no relevant commercial conflicts.

Open research record ↗

2024

Safety signalPMID 38909910

Copper deficiency myelopathy mimicking cervical spondylitic myelopathy

Excess zinc was a recurring cause of copper deficiency, and full neurologic recovery was uncommon. Case evidence is a safety signal, not an efficacy trial.

Published: 2024

Study design and methods

Design: Systematic review of 116 reports plus a case report
Population: 198 reported cases of copper-deficiency myelopathy
Intervention: Observed causes included excessive zinc exposure, often from denture cream
Outcome: Neurologic recovery after copper deficiency

Open research record ↗

2020

Does not support the tested claimPMID 31980506

Zinc acetate lozenges for the treatment of the common cold

The trial found no recovery benefit and more adverse events. Already represented in the Cochrane totals.

Published: 2020Duration: Up to 5 days

Study design and methods

Design: Randomized placebo-controlled trial
Population: 253 randomized adults; 87 participants developed colds and entered the treatment analysis
Intervention: 13 mg zinc acetate lozenge six times daily versus placebo
Outcome: Cold recovery and adverse events

Open research record ↗

2016

Mixed or qualifiedPMID 26817502

Effect of zinc supplementation on serum zinc concentration and T cell proliferation in nursing home elderly

The higher dose raised serum zinc and increased T-cell numbers, but did not normalize zinc in everyone or improve per-cell proliferation.

Published: 2016Duration: 3 monthsn=31 participants

Study design and methods

Design: Randomized double-blind placebo-controlled trial
Population: 31 zinc-deficient nursing-home residents aged 65 or older
Intervention: 30 mg zinc daily versus a 5 mg control supplement
Outcome: Serum zinc and T-cell measures

Open research record ↗

1996

Supports a specific usePMID 8678384

Zinc gluconate lozenges for treating the common cold

Median symptom duration was shorter, but adverse effects and bad taste were more common. Already represented in the Cochrane totals.

Published: 1996

Study design and methods

Design: Randomized double-blind placebo-controlled trial
Population: 100 adults with cold symptoms for less than 24 hours
Intervention: 13.3 mg zinc gluconate lozenge every two waking hours versus placebo
Outcome: Time to symptom resolution and adverse effects

Open research record ↗

Unscreened discovery appendix—not evidence863 candidate publicationsSearch run: Aug 21, 2026

Complete for the displayed PubMed query at the search timestamp—not for all databases or every possible synonym. Candidates can be irrelevant, duplicate the same study, or report negative findings. They are never summed as evidence or participants until screened.

03 / SOURCES

Start with the source material

Official evidence overviewNIH Office of Dietary Supplements Live PubMed discovery searchNational Library of Medicine

The live search is for discovery only. Search-result counts change and are not included in the audited totals above.

Recent PubMed discovery recordsDirect links to the first 12 records returned by the reproducible search. These are discovery candidates—not reviewed summaries or a count of supportive findings.

04 / EXPERT CONTEXT

Expert context—not evidence

Expert positions are dated context—not scientific evidence. They never raise the evidence status or become consensus by repetition.

No direct, source-verified endorsement is currently recorded. Research authorship or discussion alone is not treated as endorsement.