Are you getting enough zinc in your diet? Hopefully! Zinc is a mineral that plays a key role in hundreds of chemical reactions that keep your body humming along, including ones that affect fertility, wound healing, immune health, and growth.
How do you know you’re meeting your body’s vitamin needs? If you eat a vegetarian or vegan diet, you may fall short of getting enough of this essential mineral in your diet. The best sources of zinc are animal-based foods, although plants contain modest quantities of zinc, you must eat more plant-based sources of zinc to get the amount your body needs.
Why Zinc Matters
Why should you be concerned about getting enough zinc, especially during cold and flu season? Zinc is crucial for immune health, and it’s important for keeping your immune system primed during cold and flu season. Studies also show that zinc has anti-viral properties. Studies are looking at whether zinc lozenges lower the risk of COVID-19. Zinc may also slow the replication of some viruses.
Plus, research reveals zinc helps immune cells called T-cells function better when exposed to a virus or other pathogen. T-cells come in several distinct varieties and play a key role in the defense against infection. In fact, they’re the “workhorse” of the cellular component of the adaptive immune system, immune activity directed against specific pathogens. That comes in handy when you’re trying to avoid whatever virus is going around.
Can Zinc Stop the Common Cold?
The strongest evidence that zinc reins in cold symptoms are from studies where subjects took zinc lozenges. Studies are conflicting, but some research shows taking 75 milligrams daily in divided doses every 2 hours may shorten the duration of cold symptoms.
Adding further support to the idea that zinc lozenges shorten the length of cold symptoms, a study from the Cochrane Database of Evidence-Based Medicine analyzed 18 randomized-controlled trials. It concluded that taking zinc lozenges on the first day of cold symptoms reduces the duration of symptoms. The research also showed that supplementing with zinc led to fewer absences from school and work for upper respiratory infections. That’s a bonus if you don’t like taking time off for illness.
The benefits seem to be strongest with zinc acetate lozenges, although zinc gluconate lozenges show benefits too. However, all cold symptoms don’t respond to zinc. It’s most effective for limiting nose and throat symptoms, like sore throat and nasal stuffiness. Plus, early studies show zinc may slow the replication of the COVID-19 virus, further supporting its anti-viral benefits.
Although not a miracle cure, zinc lozenges are something to consider the next time you feel a cold coming on but talk to your physician before taking supplements to make sure they won’t interact with other supplements or medications. Dietary or supplemental zinc is also important for immune function, and you need a healthy immune system to fight off viruses and help your immune system respond to them robustly.
The Downsides of Zinc Lozenges
One problem with zinc lozenges is they can cause nausea and a metallic taste in the mouth that some people find unpleasant. There have also been rare reports of the sudden loss of taste and smell in people who took zinc lozenges. Stay away from zinc-based nasal sprays, since there are reports of permanent loss of smell in people who use them. It’s not clear why zinc sprays cause loss of the ability to smell in some people, but it’s a concern as the effects may be long-lasting.
Another alternative is to take an oral zinc supplement during cold and flu season to support immune health, but there is a downside. Oral zinc supplements, especially at higher doses, can cause nausea and digestive upset. The best way to reduce this side effect is to take zinc supplements with food. If you take an oral supplement, don’t exceed 40 milligrams of zinc per day, since that’s the maximum amount deemed safe for adults.
If you opt for a daily oral zinc supplement, choose one that also contains copper, since zinc and copper compete for absorption. If you take a zinc supplement without copper, you’ll absorb less copper from your diet and will be at a higher risk of copper deficiency.
Dietary Sources of Zinc
Regardless of whether you’re trying to fight off a cold, make sure you’re getting enough zinc in your diet. If you eat a lot of animal-based foods, you may already get plenty of zinc. Beef, turkey, lamb, and seafood are all excellent sources. But if you eat a vegetarian or vegan diet, the best option is to add more legumes and whole grains to your plate, as they contain zinc.
One drawback is the zinc in plant-based foods is not as bioavailable to the body, since phytates in whole grains interfere with and reduce how much zinc your body can absorb. That’s why some people turn to a zinc supplement to ensure they’re getting enough. But if you’re just trying to get enough zinc to maximize immune health, eating a varied diet of mostly whole foods should help you meet your body’s zinc requirements.
The Bottom Line
As cold and flu season draws closer, make sure you’re getting enough zinc in your diet. Keep zinc lozenges in the closet and if you feel cold symptoms coming on, use them as soon as the symptoms start, assuming your doctor approves. Doing so may help shorten how long you have to deal with the sneezing, runny nose, and sore throat that comes with a cold. Be sure to check with your doctor first before taking supplements, though.
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