Is Zinc Good When You're Sick? Exploring Its Role in Cold Relief

January 10, 2026 •

3 min read

According to a 2017 review of studies, consuming certain forms of zinc soon after symptoms appear may reduce the duration of the common cold. This finding has solidified zinc's reputation as a popular over-the-counter option for seasonal sicknesses.

Quick Summary

Zinc may shorten the duration of the common cold if taken as lozenges or syrup within 24 hours of symptom onset. Effectiveness depends on the form and timing of supplementation, and potential side effects exist.

Key Points

Start Early: For colds, oral zinc is often suggested for use within 24 hours of the first symptoms appearing.
Consider Lozenges or Syrup: Zinc lozenges (acetate or gluconate) or syrup are among the forms studied for cold support.
Avoid Nasal Sprays: Intranasal zinc products have been linked to irreversible loss of smell and should be avoided.
Use Short-Term: Zinc for colds is typically recommended only for the duration of the illness.
Monitor Side Effects: Be aware of potential side effects like nausea and metallic taste, which can be associated with oral zinc products.
Consult a Doctor: If on other medications or managing health conditions, consult a healthcare provider before using zinc supplements.

The Science Behind Zinc and Your Immune System

Zinc is a vital trace mineral essential for numerous bodily functions and is crucial for immune system development and function. It supports immune cells like T-cells and natural killer cells and acts as an antioxidant. For common colds caused by rhinoviruses, zinc ions may hinder viral replication by preventing the virus from attaching to cells.

The Impact of Zinc Deficiency

While many people get enough zinc from their diet, groups like vegetarians, pregnant women, older adults, and those with certain digestive issues may be at higher risk of deficiency. Zinc deficiency can weaken the immune system.

Zinc for Colds: What the Research Says

Research on zinc for colds has varied, but meta-analyses show that oral zinc, especially lozenges, can reduce cold duration by one to two days if started within 24 hours of symptoms. Its effect on symptom severity is less consistent.

Considerations for Use

For colds, approaches often involve taking zinc shortly after symptoms appear. It is generally recommended for short-term use during illness. Prolonged use or exceeding recommended intake levels for general health is not advised without medical guidance.

How to Get Zinc: Food vs. Supplements

A balanced diet usually provides enough zinc. Zinc-rich foods include red meat, poultry, shellfish, dairy, legumes, nuts, seeds, and fortified cereals. For colds, supplements offer targeted intake, but the form can influence effectiveness and potential side effects.

Forms of Zinc: A Comparison Table


Zinc Form	May Help With	Absorption	Common Use	Potential Side Effects
Zinc Gluconate	Reducing cold duration	Good	Lozenges, syrups	Metallic taste, nausea, mouth irritation
Zinc Acetate	Reducing cold duration	High	Lozenges	Metallic taste, nausea, mouth irritation
Zinc Picolinate	General supplementation	High	Tablets, capsules	Stomach upset (less common than sulfate)
Zinc Sulfate	Addressing deficiency	Lower	Tablets, capsules, topical	Stomach irritation, nausea
Intranasal Zinc	AVOID	Varies	Nasal sprays	Permanent loss of smell (anosmia)

Potential Side Effects and Safety Precautions

Short-term oral zinc use for colds is generally considered safe, but lozenges can cause a metallic taste, nausea, and mouth irritation. Excessive or prolonged high intake of zinc can lead to copper deficiency and neurological issues. Oral supplements can interact with certain antibiotics and rheumatoid arthritis medications. Intranasal zinc sprays and gels should be avoided due to the risk of permanent loss of smell. Always consult a healthcare provider before starting supplementation, especially if taking other medications or managing existing health conditions.

Conclusion: Making an Informed Decision

For common colds, certain forms of oral zinc, like lozenges (acetate or gluconate) or syrup, taken early in the illness may modestly shorten illness duration. The effect on symptom severity is less certain. It's not typically considered a preventative measure. While a balanced diet is usually sufficient for daily zinc needs, those considering supplements for a cold should be mindful of the form and potential side effects and interactions. Always discuss supplementation with a healthcare professional, particularly concerning appropriate use and duration. Zinc may be a complementary approach for cold relief, but rest, hydration, and other supportive care remain essential. For more information, you can refer to the NIH Fact Sheets.

Frequently Asked Questions

Current evidence does not strongly support using zinc supplementation to prevent a healthy person from catching a cold. It is most beneficial when taken therapeutically, soon after symptoms have begun.

Zinc for colds is generally recommended only for the short duration of the illness, typically no more than a few days. Continuous high intake of zinc is not advised without consulting a healthcare professional.

Research has focused on zinc acetate and zinc gluconate, particularly in lozenge or syrup form, for potentially shortening cold duration.

Yes, excessive or prolonged high intake of zinc can cause nausea, vomiting, abdominal cramps, and may interfere with copper absorption over time. Consult with a healthcare provider regarding appropriate intake levels.

While zinc is most extensively studied for the common cold, some evidence suggests it might offer some benefit for flu-like symptoms. However, the evidence is not as conclusive as for the common cold, and more research is needed.

The unpleasant or metallic taste is a common side effect associated with oral zinc products and does not necessarily indicate the supplement's effectiveness. It is a well-known consequence of high zinc concentrations in the mouth.

If you suspect you may have a zinc deficiency, it is important to consult a healthcare provider. They can assess your situation and determine if supplementation is appropriate, which is different from short-term use for cold symptoms.