Does Zinc Work for Colds?

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Zinc supports a healthy immune system. After iron, it is the second most common essential mineral in our bodies. But because our bodies can't make zinc, we have to get what we need from food or supplements. Taking supplemental zinc for colds has become more popular over time as a natural remedy to fight off the virus.

This article discusses whether zinc works for colds, its side effects, and how to take it.

Sick woman laying on sofa holding remote control.
Tom Merton / Getty Images

Benefits of Zinc for Colds

Since the original 1984 research report on zinc, more recent studies have reported mixed results about whether zinc may shorten the duration of a cold and address symptoms.

On the whole, however, studies show that zinc can help ease symptoms and the duration of illness. For zinc to be effective, it needs to be taken within a day of symptom onset and on a regular basis.

Side Effects of Zinc for Colds

Your body doesn't need much zinc to be effective, and if you overdo it, it can reduce the amount of copper in your body, which is another essential mineral. Too much zinc can also be toxic, leading to an upset stomach.

Other side effects include:

  • Zinc nasal sprays can make people lose their sense of smell, either temporarily or permanently.
  • Zinc lozenges can make you feel nauseated.
  • Zinc lozenges can leave a bad taste in your mouth.

How to Take Zinc for Colds

It's important to start taking zinc within a day of feeling a cold coming on or you may not experience any benefit. Experts continue to research the proper dosage, but it should be safe to follow the directions that come with your zinc supplements. Remember that more is not better.

Supplements

Zinc supplements come in lozenges, syrups, nasal gels, and nasal sprays. The nasal sprays have been known to cause loss of smell in some people (in some cases permanently).

There are several forms of zinc over-the-counter (OTC) supplements. They may contain zinc gluconate, zinc acetate, or zinc sulfate, and many contain more than one of these.

The different forms may have slightly different effects on the duration and severity of symptoms, but the research is not definitive on this point. You can ask your pharmacist or healthcare provider for a recommendation.

Food

If you eat a balanced diet, you should have sufficient zinc for your body to function properly. If you want to eat foods high in zinc when you feel a cold coming on, some options include:

  • Oysters
  • Beans
  • Nuts
  • Crab
  • Lobster
  • Whole grains
  • Dairy products

How Much Zinc Should I Take?

The amount of zinc required to help fight off a cold is not firmly established. However, one study of both zinc acetate and zinc gluconate lozenges found that taking 75 milligrams a day shortened colds between 12%–48%. They found no sign that taking more than 100 milligrams a day helped further shorten colds or reduce symptoms.

Talk to Your Doctor About Zinc for Colds

If you eat a balanced diet, you should have enough zinc in your system to meet your daily needs. If you want to take zinc for a cold, consider talking to your healthcare provider about how much is required.

Ask your provider if there's any reason why you shouldn't take zinc, which may include:

  • People with a copper deficiency
  • People who are pregnant or breastfeeding, since high levels of zinc may be unsafe
  • If you have been prescribed Midamor (amiloride), which can stop your body from eliminating zinc, causing it to build to dangerous levels
  • If you take an ACE inhibitor (angiotensin-converting enzyme inhibitor, often used for high blood pressure), hormone replacement (estrogen) therapy, birth control pills, or a proton pump inhibitor due to unsafe drug interactions

Summary

There is evidence to support that zinc can shorten colds and reduce symptoms. It works best when taken within 24 hours of symptom onset, but the optimal dosage is unconfirmed. Consult with a healthcare provider and follow the directions on your zinc supplement carefully if you choose to take zinc for a cold.

A Word From Verywell

Having a cold is unpleasant, and you may be tempted to try remedies like zinc to help relieve symptoms. Though experts are still determining the best dosage, there is ample evidence to show that zinc can shorten a cold and ease symptoms. It may only have mild benefits, but it can help if you start taking it soon after signs of a cold appear.

Frequently Asked Questions

  • How much zinc should you have per day?

    The recommended daily amount of zinc is 8 milligrams for adult women and 11 milligrams for adult men. Most people will get that from their normal diet. The body does not store zinc, and it eliminates what it does not need or use.

  • Can zinc increase sperm volume?

    Zinc is necessary for sperm formation, but taking zinc does not appear to increase fertility, despite some early research that claimed it might.

  • Why does zinc sometimes make you feel nauseated?

    If you take too much zinc, you may have some zinc toxicity, which can make you feel sick to your stomach.

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7 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
  1. Eby GA, Davis DR, Halcomb WW. Reduction in duration of common colds by zinc gluconate lozenges in a double-blind studyAntimicrob Agents Chemother. 1984;25(1):20-24. doi:10.1128/AAC.25.1.20

  2. National Institutes of Health, Office of Dietary Supplements. Zinc.

  3. Singh M, Das RR. Zinc for the common coldCochrane Database Syst Rev. 2011;(2):CD001364. doi:10.1002/14651858.CD001364.pub3

  4. Rao G, Rowland K. Zinc for the common cold—not if, but whenJ Fam Pract. 2011;60(11):669-671.

  5. Hemilä H. Zinc lozenges and the common cold: a meta-analysis comparing zinc acetate and zinc gluconate, and the role of zinc dosageJRSM Open. 2017;8(5):2054270417694291. doi:10.1177/2054270417694291

  6. Harvard School of Public Health. Zinc.

  7. National Institutes of Health. Zinc, folic acid supplement does not improve male fertility, NIH study suggests.