Cold-lozenge trials start 75–90 mg/day elemental zinc within 24 hours for up to 2 weeks; results depend on formulation
Reviewed · Published
Zinc
A trace element required by many enzymes, immunity, wound healing, and taste.
Established functions
- A trace element required by many enzymes, immunity, wound healing, and taste.
Dietary sources
- oysters
- beef
- pumpkin seeds
Claims and evidence
Claims that Zinc alone prevents or treats disease, or invariably improves health without deficiency, are unsupported.
Japanese reference amounts
- Japanese adults (age and sex as specified): Adult men 9.0–9.5 mg/day; women 7.5–8.0 mg/day (RDA)
Amounts studied
- Cold-lozenge trials start 75–90 mg/day elemental zinc within 24 hours for up to 2 weeks; results depend on formulation
Tolerable upper limits
- Adults: 40 mg/day
Forms and bioavailability
Supplement forms: zinc gluconate, zinc citrate
- Phytate reduces absorption; avoid intranasal zinc because of anosmia.
Safety and interactions
Adverse effects
- nausea
- copper deficiency
- lower HDL
- anosmia
Medicine and nutrient interactions
- tetracyclines, quinolones, penicillamine, copper
Contraindications and cautions
- Avoid chronic high doses and intranasal products.
Practical selection
- Compare Zinc amount per serving, form, allergens, and batch testing; prefer a single-ingredient product suited to the intended use.
Sources and review
- Dietary Reference Intakes for Japanese (2025)Ministry of Health, Labour and Welfare (Japan)
- NIH ODS mineral fact sheetsNIH Office of Dietary Supplements
Daiki Minaki (editorial and evidence review) ·