Nutrient Spotlight: Zinc

Especially as we head into cold and flu season, everyone is interested in boosting their immunity. Among the many important ways to encourage healthy immune function—including sleeping well, getting enough sunshine and fresh air, moving your body regularly, and managing stress—is eating a healthy diet. Many healthy foods contain zinc, an important nutrient in the body’s essential functions, including a healthy immune response.

Interest in immunity and zinc’s role is enhanced since the emergence of COVID-19. It should be noted, though, that the effects of zinc on COVID-19 infections is not yet established. What is known is zinc’s essential role in immune cell function and cell signaling. Adequate zinc keeps the immune system ticking. A review of seven studies showed that 80 – 92 mg per day of zinc reduced the length of the common cold by up to 33 percent.

Zinc is so important that it is present in every cell in your body. The body cannot produce it or store it, so it is crucial that we get an adequate amount from the foods we eat. In addition to its role in the immune response, the zinc we eat helps in healthy enzyme function, gene expression, wound repair, and growth and development.

So how do you get enough zinc? Fortunately, zinc is plentiful in all sorts of healthy food. So, zinc deficiency is rare. People who have gastrointestinal diseases, who are vegetarian or vegan, and are pregnant or nursing are at greatest risk of zinc deficiency.

You can find zinc in many types of meat, including shellfish, red meat, poultry, and fish; legumes, like chickpeas, lentils, black beans, and kidney beans; nuts and seeds; dairy and eggs; whole grains; and some vegetables, including mushrooms, kale, peas, asparagus, and beet greens. There is no end to the recipes that you could make using these ingredients.

I recommend a chicken minestrone with chicken, beans, whole plum tomatoes, chopped mushrooms, shredded kale, and whatever other vegetables you like. For an authentic vibe, simmer with a parmesan rind and a bay leaf or two. A kale and spinach salad with chopped eggs, feta cheese, a whole grain, like farrow, and an olive oil and balsamic vinegar dressing would be tasty and satisfying. A serving of farrow includes 15 percent of the recommended daily amount of zinc. For the traditionalist, you could have your favorite roast meat, some brown rice, and peas or asparagus.

Zinc is so important that extra zinc is put into some prepared foods, like ready-to-eat breakfast cereal and granola bars. These foods are known as “fortified.”

While too much zinc can be toxic, it is unlikely that you would get too much from diet alone. Supplements, though, can cause zinc toxicity, and are not recommended for most people. Talk with your doctor before taking a zinc supplement.

Most of us can enjoy incorporating more healthy foods into our diets knowing that they are a good source of zinc and that zinc helps keep our whole body—including our immune system—strong.

Kristin Irace, RD, is a registered dietitian at Southwestern Vermont Medical Center.