6 Vitamins Doctors Take So They Don’t Get Sick During Virus Season

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Virus season is right around the corner, and ensuring you’re getting enough of the nutrients responsible for immune health is important for reducing your risk of picking up infections, explains Julia Zumpano, RD, Registered Dietician at the Cleveland Clinic Center for Human Nutrition. Recent research published in Nutrients shows that even if you catch a respiratory virus like Covid this season, maintaining good nutrition may reduce your symptoms.

In general, getting your nutrients from food is ideal. Zumpano explains that supplements are poorly regulated often aren’t as bioavailable as the nutrients in food, and may not be absorbed well if you take them incorrectly. But realistically, “most Americans do not meet their needs through food,” she says. “The Standard American Diet (SAD) is inadequate in nutrition due to high intake of processed, low-nutrient foods.” In fact, less than 15% of Americans meet daily fruit and vegetable recommendations, according to Ali Bandier, MS, RD, a registered dietitian from New York.

So, while shifting to a whole, nutrient-dense food diet is the best way to ensure you’re getting your immune-boosting vitamins, supplements can help fill gaps as we head into cold and flu season. Elderly people, vegans, vegetarians, those with blood tests that indicate a deficiency, or those who practice strict dietary restrictions (such as low-calorie, keto, or dairy-free) can benefit from supplementation as well, says Zumpano.

She says to always use supplements that are third-party tested “and be sure they do not interact with any medications or other supplements you are taking.” (Here are 13 supplement and medication combos experts say you should never mix.)

What’s more: “Oftentimes, we want a quick fix, but maintaining a healthy lifestyle will aid more than a supplement can.” That’s why she advises boosting your immunity by getting enough sleep (seven to nine hours per night), drinking enough water (about half your body weight per day), exercising and prioritizing stress reduction—while also aiming to get more nutrients through food intake. 

Still, supplementing the right nutrients can make a big difference in staying healthy for some of us. To help you fend off the flu or curb the cold, health professionals share the select few vitamins and supplements they do reach for during virus season.

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1. Vitamin C

Though vitamin C can’t prevent colds according to the National Center for Complementary and Integrative Health, a 2017 study published in Nutrients suggests it is still a vital nutrient for a strong immune system.

“The best way to get adequate vitamin C is through food, and those that are high in it include citrus fruits like oranges, grapefruit, and kiwi; cruciferous vegetables like raw broccoli and Brussels sprouts; as well as strawberries, tomatoes, and white potatoes,” Bandier says.

2021 research published in BMJ Global Health found that vitamins C and D reduced the risk of acute respiratory infections and shortened the duration of symptoms. A 2022 meta-analysis published in Current Reviews in Clinical and Experimental Pharmacology also found that vitamin C can reduce the duration of respiratory tract infections.

In addition to a daily multivitamin, Bandier takes a supplement with elderberry, vitamin C, vitamin D, and zinc during cold and flu season. (Sometimes she takes a Lypo-C, a vitamin C supplement that claims to be easily absorbed in the body, Bandier adds.)

Michael Miller, MD, a cardiology professor at the University of Pennsylvania, tells The Healthy that he doesn’t take a multivitamin (or any vitamin supplements) regularly because it’s healthier to obtain them naturally through your diet. However, when he gets sick, he occasionally reaches for vitamin C.

“I will take 2 grams of vitamin C supplements twice daily when I have a cold because vitamin C has been shown to reduce the symptoms and duration associated with a cold. I have been doing that since medical school,” Dr. Miller says.

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2. Vitamin D

Many people don’t get enough vitamin D in their diets—unfortunately, it’s hard to. Few foods naturally contain vitamin D (though fatty fish, eggs, mushrooms, and fortified foods are good sources), and the best way to get adequate levels of vitamin D is through sunlight exposure, which can be tricky during the winter months. Yet vitamin D plays an important role in regulating our immune system—and low levels can increase your risk of picking up an infection. The Cleveland Clinic estimates around 35% of Americans have a vitamin D deficiency. 

That’s why taking a vitamin D supplement seems to be high on the list for many medical professionals. A 2022 study published in Frontiers in Nutrition suggests that vitamin D can help ward off the flu.

“I make sure that I am getting a good source of vitamins C, D and E in my diet through whole foods and supplements. I take vitamin D,” says Sharon Palmer, RDN, a registered dietitian nutritionist from Ojai, California.

Like Palmer, Zhaoping Li, MD, PhD, a professor of medicine and chief of the Division of Clinical Nutrition at UCLA, says she also takes vitamin D. (Dr. Li tells The Healthy that a balanced diet, enough sleep, and regular exercise are just as important for a healthy immune system.)

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3. Vitamin E

Vitamin E is a powerful antioxidant that can strengthen immune function, Bandier says.

“The best form to get vitamin E is through food,” Bandier adds. “Vitamin E deficiencies are rare, so like with anything else, too much can be harmful. Excellent sources of vitamin E include seeds and nuts/nut butters; dark leafy greens, like spinach and broccoli; fruits such as kiwi, tomatoes, and mango; and wheat germ oil.” 

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4. Zinc

Zumpano points to zinc as an important mineral for immune system support. It’s necessary to help build new immune system cells—and researchers theorize that zinc may reduce the severity and duration of virus symptoms (especially if you take it within 24 hours of symptom onset). 

Recent research has even found that zinc has positive effects and potential therapeutic benefits for treating Covid, but more research is needed to understand its role in combating viral infections. 

Most multivitamins contain zinc—or you can take it as a standalone supplement. But if you’re opting for dietary sources, foods like oysters, crab, lean meats and poultry, baked beans, chickpeas, and yogurt contain high levels of zinc.  

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5. Omega-3 fatty acids

Dr. Li also regularly takes fish oil for its immune system benefits, though according to the Cleveland Clinic, the research tends to go back and forth on who should take these supplements and how much.

Depending on your diet—for example, if you don’t eat fish—you may not get a lot of this nutrient. Popping an omega-3 fatty acid supplement can be a good solution.

Palmer says she’s been prioritizing good sources of omega-3 fatty acids in her diet for over a decade. “I include mushrooms in my diet daily, lots of fiber and probiotics, and a source of omega-3 fatty acids, too,” Palmer says.

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6. Probiotics

”Your gut microbiome is an intricate system of bacteria, some of which can support immunity,” Zumpano says. Recent research published in the journal Cells points to data showing that probiotic supplements positively support our intestinal bacterial composition—improving our body’s immune function. 

However, “we are still learning which specific organisms and how these organisms do support immunity,” Zumpano says. That’s why it’s ideal to obtain probiotics through dietary sources (unless your doctor recommends a supplement). 

Some of the best probiotic dietary sources include kombucha, kimchi, kefir, sauerkraut, tempeh, miso, natto, and other fermented foods. Zumpano adds that you’ll also want to include prebiotic foods in your diet as these feed the probiotic bacteria. Prebiotics are found in foods high in fiber, such as garlic, onion, leeks, banana, Jerusalem artichokes, barley, oats, apples, pears, flaxseeds, wheat bran, and seaweed.

Which vitamins for virus season are best?

There’s a reason experts recommend few vitamins. Many doctors don’t take many supplements—or any at all.

For example, Christopher Gardner, PhD, a professor at Stanford University and chair of the American Heart Association’s Nutrition Committee. Dr. Gardner told us he’s in his sixties and has never taken supplements. “I don’t ever remember missing a lecture, an event, a celebration, or a meeting due to illness,” Gardner says. “I suppose every four to five years, I get a mild cold.”

So, what’s his secret? “I eat a whole-food plant-based diet and like to cook. I get a good variety of healthy foods, all the time,” Gardner says. “All my nutrients and antioxidants come from food.”

Keep your immune system running smoothly with daily updates from The Healthy @Reader’s Digest newsletter and follow The Healthy on Facebook and Instagram. Keep reading:

• 10 Foods That Could Make Your Cold or Flu Worse
• 12 Vitamin Mistakes You Might Not Realize You’re Making
• 17 Natural Cold Remedies That Really Work
• 8 Vitamin Secrets Doctors Tell Their Friends

With additional reporting by Leslie Finlay, MPA.