The Pros and Cons of Taking Zinc for a Cold

When you’re miserable and sniffling and sneezing, you may be ready to try anything — anything — to make it stop. Or maybe you would do anything to prevent those symptoms from starting. A Keck Medicine of USC expert weighs in on using zinc to fight and prevent colds.

Runny nose, sore throat, aches and congestion are all too familiar symptoms of the common cold. You’ve tried the pills and the syrups and tea with lemon and honey, but your symptoms stubbornly persist. Then, someone helpfully tells you to try zinc. Should you? Here’s what you need to know. 

What are the benefits of zinc for a cold? 

Zinc is a mineral your body needs for your immune system, among others, to function properly. The National Institutes of Health says supplemental zinc appears to reduce the duration, but not the severity, of cold symptoms.  

Lisa Statner, MS, RDN, CSO, a clinical dietitian with Keck Medicine of USC, explains that zinc helps activate T-cells that destroy infected cells. In fact, several studies have shown that zinc, particularly in the form of zinc acetate, may reduce the number of days you’re sick by inhibiting the replication of rhinovirus, which is one of the most common viruses responsible for the common cold. 

What are the best food sources of zinc? 

There are many dietary sources of zinc — protein in particular. Oysters provide the highest amount of zinc. Beef is another good dietary source. Others include dark-meat chicken, miso soup, quinoa, hominy, garbanzo beans and eggs. 

It also turns out that the benefits of Grandma’s chicken soup for a cold are not a myth. Beyond its comforting warmth, chicken soup, especially soup made with dark chicken meat, provides a good dose of zinc.  

A word of caution: Statner warns that some food components can block zinc absorption. These include casein in milk, phytates in legumes and grains, as well as foods high in fiber. Fortunately, the solution is as simple as spacing out your intake of zinc and these potential inhibitors by two hours, she says. 

Those following a vegetarian diet may also be at risk of zinc deficiency, Statner adds. The bioavailability of zinc from vegetarian diets is lower than from nonvegetarian diets because vegetarians typically eat large amounts of legumes and whole grains, which contain phytates that bind zinc and inhibit its absorption. Vegetarians and vegans might benefit from using certain food-preparation techniques that reduce the binding of zinc by phytates and increase its bioavailability, such as soaking beans, grains and seeds in water for several hours before cooking them.  

Should I take a zinc supplement for a cold? 

If you have a cold, could you benefit from taking a zinc supplement in addition to consuming zinc-rich foods? Do zinc supplements work for a cold? 

In a 2024 meta-analysis, researchers found that zinc lozenges shortened colds in adults. This effect was particularly notable for zinc acetate and zinc gluconate lozenges providing more than 75 mg/day of elemental zinc. Researchers are exploring how zinc lozenges may work through local effects in the throat and mouth — particularly zinc acetate lozenges, which release free zinc ions and make it more difficult for cold-related viruses to get a foothold.  

Are there any downsides to taking zinc supplements for a cold? 

While zinc supplementation may shorten the duration of your cold, the sniffling, sneezing and other symptoms won’t improve in the interim.  

Statner advises care if taking over-the-counter zinc lozenges every couple hours, which can lead to high daily intake of zinc. She cautions that taking zinc doses over 100 mg/day hasn’t shown better results and that high doses may cause side effects like nausea, intestinal distress and diarrhea.  

There are also potential drug interactions when zinc is paired with antacids; NSAIDs such as ibuprofen, naproxen, piroxicam and indomethacin; and certain chemotherapy drugs. Check with your doctor or pharmacist for guidance. 

Some people also complain they don’t like the taste of zinc (described as metallic). Nasal sprays may be an alternative to oral supplements. Statner also recommends taking supplements with food to avoid nausea. 

Tips for using zinc to shorten your cold 

If you have a cold, don’t wait for full-blown symptoms to arrive, Statner says. Start taking zinc at the very first signs of a cold for best results. To improve absorption, take zinc supplements with protein-rich foods or vitamin C, but avoid taking them with dairy products or high-fiber meals. Before starting zinc supplements, check with your health care provider if you have any concerns or take medications. 

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