The 4 Best Supplements for COVID-19

Nature Made Vitamin D3 may help support your immune system

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Since the start of the COVID-19 pandemic, there have been dozens (if not hundreds) of claims for alternative remedies to prevent and treat the virus. Unfortunately this has led to a lot of misinformation about how to stay well, and it is hard to know what to take seriously. When it comes to preventing serious illness, “getting vaccinated and boosted is the best thing you can do to protect yourself. When fully vaccinated and boosted, you have a lesser chance of becoming sick or as severely ill,” says Paul Thottingal, MD, national infectious disease physician for Kaiser Permanente. 

It’s also important to keep up with CDC guidance and to follow additional precautions if you’re at increased risk for serious illness and complications. “To prevent illness, hand washing, social distancing, and mask-wearing are still important for those at increased risk of infection and in areas with increased community-level COVID-19 spread, even when mandates are relaxed,” adds Emily LaRose, DrPH, MS, RD, Nutrition and Global Health Consultant to Meedan’s Health Desk.

In addition to vaccination, supporting your immune system with healthy habits may help you fight off illness more quickly if you are exposed. This includes “eating a varied diet with plenty of fruits and vegetables, getting enough sleep, regularly exercising, managing stress, not smoking, and avoiding alcohol,” says LaRose. 

Supplements do not replace a healthy diet, but certain supplements, especially vitamin and mineral supplements, may play a role in supporting a healthy immune system if you aren’t getting enough through food. If you’re considering a supplement to support your immune system, work closely with a healthcare provider to determine the best one for you. This is especially important if you have any underlying medical conditions or take prescription medications as many supplements can interact with medications or make illness worse.

Verywell Health Approved Supplements for COVID-19

  • Best Vitamin D Supplement: Nature Made Vitamin D3 can help you meet your vitamin D needs if you’re not getting enough from food and the sun. We like that it comes in three doses, so you can choose the amount that is best for you based on your current vitamin D status.
  • Best Vitamin C Supplement: Nature’s Bounty Vitamin C 500mg’s may be helpful in supporting the immune system, especially if you have low vitamin C levels or elevated needs.

Always speak with a healthcare professional before adding a supplement to your routine to ensure that the supplement is appropriate for your individual needs and which dosage to take.

Are Supplements Beneficial for Preventing or Treating COVID-19?

“There has been a lot of discussion about the role of dietary supplements in treating or preventing COVID-19. The CDC, National Institutes of Health (NIH), and Infectious DIsease Society of America have looked into whether they can help, and they all agree that there is currently no evidence to support that they do,” says Thottingal. 

That said, there is some evidence to suggest that supplements may be helpful for some people. 

  • People with known nutrient deficiencies. It’s well established that vitamins A, C, and D as well as zinc, iron, and selenium play an important role in the immune system, and deficiencies can make you more susceptible to illness and less able to fight off illness quickly. Vitamin and mineral supplements can help close nutrient gaps to support your immune system.
  • People with poor absorption. Those with poor nutrient absorption related to illness, especially those affecting the digestive tract, may benefit from supplements to achieve optimal nutrient status.
  • People that restrict entire food groups or eat a very limited diet.  Avoiding entire food groups or eating a limited number of foods may put you at risk for nutrient deficiencies, in which case a supplement could help support a healthy immune system.

Who May Not Benefit from Supplements

  • People who eat a well-balanced diet. “For most people with varied diets, vitamins, minerals, and other supplements are unlikely to provide any benefit or prevent COVID-19 infection,” says LaRose. One exception may be vitamin D as the primary source of this nutrient is sunshine and it’s not available in many foods. Because vitamin D deficiency is relatively common, even those that eat a well-balanced diet may benefit from supplementation.
  • People taking certain medications. Many vitamin, mineral, and herbal supplements interact with medications and can reduce effectiveness or increase the amount the body absorbs, which can be dangerous. If you take any prescription or over-the-counter medications, check with a healthcare provider before starting a supplement.
  • People with certain underlying conditions. While being immunocompromised may put you at higher risk for severe illness and complications from COVID-19, that doesn’t mean you should take supplements to prevent it. Some supplements can actually make conditions worse, so review any supplements you’re considering with a healthcare provider before starting one.

Supplements do not prevent or directly treat COVID

In general, it’s best not to rely on supplements for treating COVID-19. “Anyone with suspected or confirmed COVID-19 should work with their healthcare provider on testing, symptom management, and treatment options; there are medications to treat COVID-19 that may be available for some people,” advises LaRose.

Best Vitamin D: Nature Made Vitamin D3 1000IU Softgels

Nature Made Vitamin D3 1000IU Softgels


  • USP verified

  • Budget-friendly

  • Available in multiple doses

  • Not vegetarian or vegan

Vitamin D plays an important role in the immune system. While some research suggests a possible connection between vitamin D deficiency and more severe COVID-19 illness, the research is still inconclusive.

There are several factors like other health conditions and race that are associated with both low vitamin D status and higher risk of severe COVID-19 illness, so it’s not clear if having low vitamin D actually puts you at risk for worse outcomes. In fact, one study that accounted for those factors found no relationship between low vitamin D status and worse outcomes from COVID-19.

That said, vitamin D deficiency is common, and if you are deficient in vitamin D, taking a supplement may be warranted since it’s hard to get enough through diet. Adequate vitamin D stores support your immune system, which may reduce your risk of severe disease and help you recover faster. In addition, vitamin D supplements are well tolerated by most people and don’t pose health concerns when taken in appropriate doses. 

If you need a supplement, Nature’s Made vitamin D is a good choice for both replenishing and maintaining vitamin D levels. It’s USP verified, which means it contains what the label says and doesn’t have any harmful contaminants. It also comes in 3 dose levels—1,000 IU, 2,000 IU, and 5,000 IU—and the right dose for you will depend on your blood levels (which is why we recommend having a healthcare provider check your vitamin D before taking a supplement). 

The recommended dietary allowance (RDA) is 600 IU for most adults, though emerging research suggests that we may actually need up to 2,000 IU to maintain adequate stores for health benefits beyond just bone health. Even more may be needed in the short-term to correct a deficiency.

This vitamin D supplement contains gelatin, which is derived from animal sources, so it is not appropriate for vegans and vegetarians.

Active Nutrient: Vitamin D3 | Dose: 1,000 IU | Form: Softgel | Servings Per Container: 180

Best Vitamin C: Nature's Bounty Vitamin C

Nature's Bounty Vitamin C


  • ConsumerLab top pick

  • Free from major allergens

  • Pills not overly large

  • Uncoated tablets are unpleasant to some

Vitamin C is currently being explored for use in both preventing and treating COVID-19 given its important role in the immune system. Thus far, the findings are mixed, but it may be useful in combination with other treatments in people that do get COVID-19, especially for those with severe illness.

“We do not have evidence that suggests that vitamin C will prevent COVID-19 infection for people with normal vitamin C levels. For people with low vitamin C levels or those with higher needs than the general population such as older adults, smokers, people who regularly consume alcohol, and pregnant people, routine vitamin C supplementation may be helpful,” says LaRose.

Most people can consume enough vitamin C by eating a variety of fruits and vegetables. But for those that might benefit from a supplement, we recommend Nature’s Bounty Vitamin C 500mg. The Recommended Dietary Allowance (RDA) is only 75mg for women and 90mg for men, but studies that have shown benefits of vitamin C supplementation on reducing the length of a cold use higher amounts between 200 to 1,000mg per day. This dose is well below the tolerable upper limit (UL) of 2,000mg. 

Nature’s Bounty Vitamin C is a ConsumerLab top pick and is free from major allergens. It’s also a simple supplement, with no nutrients aside from vitamin C, which makes it safe for most people. However, if you take any medications or are prone to kidney stones, check with a healthcare provider before starting a supplement.

Active Nutrient: Vitamin C (ascorbic acid) | Dose: 500mg | Form: Capsule | Servings Per Container: 100

Best Zinc: Thorne Research Zinc Picolinate, 30 mg

Thorne Research Zinc Picolinate, 30 mg

Thorne Research

  • NSF Certified for Sport

  • ConsumerLab approved

  • Zinc is the only active ingredient

  • May be a higher dose than you need

Initial studies suggest that low zinc levels may be related to worse COVID-19 outcomes, but more research is needed. Zinc supplementation has been tested in conjunction with other medical treatments and has shown some promise in those who are hospitalized but not those who are in the intensive care unit. We also don’t have enough evidence to support adding zinc supplements for those who get enough zinc through food, and high doses are not recommended.

Zinc is found in seafood, beef, beans, nuts, whole grains, and dairy products, and most people consume enough through food. However, vegetarians and vegans have higher zinc needs since phytates found in whole grains and beans may reduce absorption. Certain gastrointestinal disorders and some medications may also reduce absorption. In these cases, a supplement may be helpful to achieve optimal levels for immune support. 

Thorne’s Zinc Picolinate 30 mg is a top choice for a zinc supplement. Many zinc supplements are paired with other nutrients, but this one provides zinc only, which helps ensure you don’t overdo it with other nutrients you may not need. The 30mg dose is higher than the RDA of 11 mg for adults (12mg for lactating people) which means that even if you don’t absorb the entire dose, you’re still likely getting enough to meet your needs. It’s also well below the UL of 40mg—many zinc supplements provide high doses over that UL that are not recommended.

Thorne is a well-trusted supplement brand that is NSF certified for sport, gluten-free, soy-free, and dairy-free, making it a good choice for most people.

It’s important to note that prolonged high-dose zinc supplementation may lead to copper deficiency, so be sure to check with a healthcare provider if you’re considering a supplement.

Active Nutrient: Zinc Picolinate | Dose: 30 mg | Form: Capsule | Servings Per Container: 60

Best Omega-3: Nordic Naturals Ultimate Omega Softgels, 1280 mg

Nordic Naturals Ultimate Omega Softgels, 1280 mg


  • Contains EPA and DHA

  • Made from wild-caught fish

  • Non-GMO

  • May not be appropriate for someone with a fish allergy

Early observational studies suggest that women (but not men) who take omega-3 fatty acid supplements may have a slightly lower risk of getting COVID-19, but more research is needed to understand the relationship and whether or not to recommend supplements. In addition, because of omega-3’s potential role in reducing inflammation, it’s thought that they could be helpful in treating COVID-19. Trials are currently underway to explore potential benefits.

If you don’t regularly eat fatty fish, you may benefit from a supplement. While it may or may not help, low dose omega-3 supplements are safe for most people. The biggest concern with supplements is increased risk of bleeding, especially before surgery, though a recent review of over 50 studies suggests there may be no increased risk afterall. To be safe, always check with a healthcare provider before starting a supplement if you’re taking a blood thinner or at increased risk for bleeding. 

We like the Nordic Naturals Ultimate Omega, which delivers 1,280mg of omega-3s including both EPA and DHA, both of which may lower inflammation and reduce risk for cardiovascular disease—an underlying condition that can make you at higher risk for severe COVID-19 illness. Nordic Naturals is known for its high quality supplements and rigorous third-party testing to ensure safety. It’s also made with lemon flavor, to reduce post-supplement fish burps.

Of note, the Ultimate Omega is made from wild-caught sardines and anchovies, so it may not be safe for someone with a fish allergy.

Active Nutrient: Omega-3s | Dose: 1,280 mg | Form: Softgel | Servings Per Container: 30

Final Verdict

The research doesn’t currently support recommending any specific supplements to prevent or treat COVID-19. However, depending on your diet and nutrition status, you may benefit from one of the above supplements to help support your immune system, which may promote a quicker recovery from any illness, including COVID-19. If you are low in vitamin D, we recommend NatureMade vitamin D3 for a high-quality, affordable option, and if you have low levels of vitamin C you may especially benefit from Nature’s Bounty vitamin C.

Supplements We Do Not Recommend at This Time

  • Probiotics. Initial research suggests probiotics offer small benefits in very specific cases, but not enough is known to make a recommendation at this point. Probiotics are highly individualized and there are dozens of strains (with more being discovered regularly), and as of now we don’t know which—if any—specific strain may be helpful in preventing or treating COVID-19. In addition, probiotics can also make some digestive related conditions worse if you choose the wrong one. 
  • Quercetin: Although some very small preliminary studies show promise that quercetin supplements may reduce severity of illness, these studies had several limitations. There is not enough evidence to support recommending quercetin supplements for preventing or treating COVID-19 right now. In addition, quercetin supplements may interact with common medications like antihistamines and cholesterol-lowering medications.
  • Magnesium. Magnesium plays an indirect role in the immune system, so it has been discussed as a possible therapy for COVID-19. Currently the evidence to support magnesium supplementation is lacking. In fact, one study showed that both high and low magnesium levels were associated with COVID-19 hospitalization. This has been seen in hospitalizations unrelated to COVID-19, too. Therefore, until more research is done on the possible benefits of supplementation, it’s not recommended at this time.
  • Selenium: Selenium plays an important role in the immune system. While preliminary data suggests a link between low selenium status and risk of severe disease, the quality of evidence is low and studies have been very small, so there’s not enough data to support supplementation. Since selenium deficiency is rare, there’s likely no benefit to adding a supplement.
  • Vitamin E. Vitamin E plays an important role in immune function and may help lower inflammation. However, vitamin E deficiency is rare and there’s no research to support supplementation when you consume enough through food. 

Other supplements like echinacea, elderberry, ginseng, NAC, and melatonin have been discussed as possibly helpful in preventing or treating COVID-19, but there is currently no research to support these recommendations, and they are not essential for supporting immune health.

How We Select Supplements

Our team works hard to be transparent about why we recommend certain supplements; you can read more about our dietary supplement methodology here

We support supplements that are evidence-based and rooted in science. We value certain product attributes that we find to be associated with the highest quality products. We prioritize products that are third-party tested and certified by one of three independent, third party certifiers: USP, NSF, or ConsumerLab. 

It's important to note that the FDA does not review dietary supplements for safety and effectiveness before they go to market. Our team of experts has created a detailed, science-backed methodology to choose the supplements we recommend.

What to Look for in COVID-19 Supplements

Third-Party Testing 

Supplements that are third-party tested are sent to a lab where they are tested to ensure they contain what they say they contain and are not contaminated with specific high-risk, common contaminants. However, it’s important to note:

  • Third party testing does not test to see if a product is effective or safe for everyone, and it does not ensure the supplement will not interact with other supplements or medications.
  • Not all third-party testing is created equal. It is not uncommon for supplement companies to pay labs for certificates after conducting minimal to no testing. 
  • The third party certifications we can trust are: ConsumerLab, NSF, and USP. However, these certifications are difficult to obtain and/or expensive for manufacturers, so many companies choose not to get their products tested by one of these three organizations. 
  • Sometimes products tested by these three companies are more expensive to try to offset the cost they pay for certification.
  • Just because a supplement is not tested by one of these three companies, it does not mean it’s a bad product. We recommend doing some research on the reputability of the manufacturer, and calling up the manufacturer and their testing lab to determine their protocols and decide if you feel comfortable consuming the supplement.


Each vitamin or mineral supplement discussed in this article comes in more than one form. We’ve recommended a form that is supported by research, but there may be additional forms that are appropriate for you in some cases. Please discuss the best form of each supplement with a healthcare provider. 

Ingredients & Potential Interactions

It is essential to carefully read the ingredient list and nutrition facts panel of a supplement to know which ingredients and how much of each ingredient is included, relative to the recommended daily value of that ingredient. Please bring the supplement label to a healthcare provider to review the different ingredients contained in the supplement and any potential interactions between these ingredients and other supplements and medications you are taking.

Many of the supplements recommended above are available in combination with other nutrients, which may or may not be beneficial for you. In most cases, it’s best to choose a supplement that only contains the vitamin or mineral you are aiming to replenish, but there may be cases where combinations such as zinc and vitamin C or zinc with copper may be helpful. Please discuss the best option for you with a registered dietitian or a healthcare provider.

COVID-19 Supplement Dosage

Always speak with a healthcare professional before adding a supplement to your routine to ensure that the supplement is appropriate for your individual needs and to understand which dosage to take.

With the exception of omega-3 fatty acids,  each of the micronutrients recommended in this article (vitamin D, vitamin C, and zinc) have RDAs established by the National Institutes of Health Office of Dietary Supplements. The recommended dose for you will vary by nutrient and the amount that’s appropriate for you will depend on your diet, health status, and any medications you take. 

How Much is Too Much?

It’s important to ensure that you don’t exceed the upper limit as established by the National Institute of Health Office of Dietary Supplements

Your body filters and eliminates excess water-soluble vitamins like vitamin C, so it is difficult to over-consume these. However, fat-soluble vitamins like vitamin D can be stored in fat tissue and are dangerous when consumed in excess. Zinc can be damaging and lead to many negative side effects if consumed in excess.

You can help ensure that you are not exceeding micronutrient upper limits by running your multivitamin pick by a healthcare provider before you start taking it, sticking to a reputable brand, and getting annual blood work to make sure your micronutrient levels are within the normal range.

Frequently Asked Questions

  • Do supplements help treat COVID-19?

    “There are not any foods or dietary supplements that effectively treat COVID-19,” says LaRose. According to the National Institutes of Health Office of Dietary Supplements, the data does not support recommending for or against using supplements as part of a treatment plan for COVID-19. Supplements may be safe in certain instances, but there’s not enough evidence to show that they help. Research is ongoing in this area.

  • Do supplements help prevent COVID-19?

    Currently there is no research to suggest that supplements prevent COVID-19. “For most people with varied diets, vitamins, minerals, and other supplements are unlikely to provide any benefit or prevent COVID-19 infection,” says LaRose.

    The best way to reduce risk of getting COVID-19 is to get vaccinated and boosted. After that, “follow CDC guidance. Avoid high risk environments and wear a mask in crowded areas when transmission levels are high. If you are exposed, get tested and follow CDC guidelines,” says Thottingal. Practicing good hygiene practices like handwashing may also reduce transmission.

  • Does vitamin D help with COVID-19?

    “Vitamin D is important for immune function, and low vitamin D levels have been associated with illnesses, including COVID-19 infection. However, other factors, including advanced age, high blood pressure, and brown or black skin color, are associated with both a risk of low vitamin D levels and COVID-19 infection which makes the relationship between vitamin D and COVID-19 infection less clear. For people who have normal vitamin D levels in their bodies, we do not have evidence that suggests that more vitamin D will prevent or treat COVID-19,” says LaRose. 

    However, if your vitamin D levels are low, a supplement can help you achieve optimal levels for immune health. Have a healthcare provider check your vitamin D blood levels and then work with them to determine if a supplement is warranted.

  • Does Vitamin C help with COVID-19?

    “Vitamin C is important for immune function, and low vitamin C levels have been associated with illnesses and poor wound healing. However, studies have not shown that vitamin C prevents colds or viruses, and vitamin C supplementation does not effectively treat COVID-19 infection,” says LaRose.

    There’s no evidence to suggest that taking extra or mega-doses of vitamin C prevents or treats Covid-19, and vitamin C deficiency is rare. That said, if you don’t get enough through diet, supplements are effective at providing you with what you need, and a robust immune system will help you fight off illnesses, including COVID-19. Research is ongoing to understand if supplements can help with critically ill patients.

  • Do any supplements make COVID worse?

    There are currently no known supplements that make COVID-19 worse. However, with hundreds of supplements on the market today—very few of which have been studied in the context of COVID-19—it’s difficult to know what supplements, if any, make symptoms worse yet. Many supplements do interact with medications and can worsen symptoms of other health conditions, so if you have COVID-19, please discuss a treatment plan with a healthcare provider.

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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.
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