Boosting Your Immune System: 16 Science-Backed Tactics to Fight Coronavirus (Covid-19)

On top of risk-reducing practices like social distancing, and sanitization, maintaining a healthy immune system is equally as important when it comes to reducing your susceptibility to coronavirus.

Currently, most preventative strategies are oriented around bolstering the immune system and reducing baseline inflammation levels. ⁽¹⁾

In such instances, the body is ultimately able to detect and respond to foreign viral invaders more efficiently, blunting any serious inflammatory response, and lessening the overall severity of the virus. ⁽²⁾

But in order for your immune system to perform at its best both in terms of preventing and responding to the coronavirus, there are certain things your body needs.  From fundamental health practices to immunity-supporting supplements and substances, we’re going over 16 different immunity-bolstering tactics you can use to fight off COVID-19.  

Before we dive into the list, however, let’s first go into a little more detail on how coronavirus actually affects the immune system.  This way we’ll have a better understanding of how and why the tactics we’re discussing later on actually work.  

Coronavirus and the Immune System

Current research on COVID-19 suggests that the virus affects the immune system in multiple ways.  First, the SARS-CoV-2 virus has been shown to evade the body’s innate immune response -- the innate immune system refers to the various defense mechanisms your body has in place to fight off antigens immediately after they enter the body. ⁽³⁾

On top of that, research findings also suggest that coronavirus may weaken the immune system through killing off macrophages as well.  Macrophages are ubiquitous cells found within the innate immune system whose primary function is to dismantle and dispose of invading pathogens. ⁽⁴⁾

The diminished response of the body’s innate immune system, coupled with the depletion of pathogen-fighting macrophages, in turn, leads to a blunted activation of the body’s adaptive immune system. 

The adaptive immune system is made up of highly specialized cells that help to kill off pathogens by hindering their ability to grow and spread.  As opposed to the innate immune system, which has an immediate response, the adaptive immune response can take days -- or even weeks in some cases -- to fully kick in.   

However, in cases in which macrophages are severely depleted, the body is ultimately unable to detect and present antigens to T cells -- it’s through T cells that the adaptive immune response is ultimately engaged.  In such instances, the body may not be able to perform the tasks required to stay on top of the virus, which in turn, can lead to dangerous levels of inflammation.   

Therefore, the foremost clinical approach to fighting coronavirus is oriented around supporting both the innate and adaptive immune systems, so that in the instance in which infection does occur, the body is well-prepared for a robust immune response. ⁽⁵⁾

But what can you actually do to bolster your immune system?  

In the following sections, we’ll be going over some different lifestyle practices along with various supplements and substances that have been shown to support your immune health.  While the following tactics may not make you immune to the virus, they can help to improve your recovery time and reduce the likelihood that you’ll experience severe symptoms if you do get infected.  

Foundational Practices To Support Your Immune Health

1. Reduce Stress

One of the biggest things you can do to bolster your immune health is to reduce your stress levels.  The unfortunate reality is that many of us lead stressful lives; whether it’s at home, at work, or anywhere else for that matter, most of us are exposed to stressors on a daily basis.  However, finding ways to reduce the amount of stress in your life is a simple and effective way to support your immune system.  

Stress ultimately causes an inflammatory response in the body, which research shows can impinge on the ability of the immune system to function properly.  More specifically, stress chemistry appears to prevent the response of certain T cells -- mainly Th1 helper cells -- in the defense against foreign viral invaders.  

Current research findings show that many people who experienced severe symptoms after being infected by the coronavirus had ultimately been going through chronic stress in the time leading up to infection. ⁽⁶⁾

While minimizing the amount of stress in your daily life can be challenging, things like exercising regularly and staying active can be an easy way to blow off some steam.  On top of that, certain nootropic substances like ashwagandha and ginseng have also been shown to reduce stress levels as well. ^(7)(8)(9)

2. Eat A Healthy Diet

On top of managing your stress levels, staying on top of your nutrition can also be an effective way to bolster your immune system in the midst of COVID-19.  Research shows that impaired glucose tolerance and insulin resistance are both factors that increase the risk of experiencing severe virus-related health outcomes -- ultimately, that’s why the virus is especially dangerous for diabetics. ⁽¹⁰⁾

Managing your body’s glycemic control is important for keeping your baseline levels of inflammation at a minimum  -- impaired glucose tolerance and insulin resistance both raise your levels of inflammation, which as we’ve already discussed, can hinder your immune response. ⁽¹¹⁾

Attaining optimal glycemic control ultimately depends on your diet.  Every type of food naturally elicits a different glycemic response by the body when consumed.  In general, in order to achieve healthy glucose levels, you’ll need to remove foods from your diet that cause a high glycemic response.  

Although there is some variation in terms of how each person responds to different types of foods, we do know that there are some foods that have inherently large glycemic loads.  More particularly, highly processed foods with trans and oxidized fats along with added sugars and/or chemicals are known to be highly inflammatory and should be removed from any diet where achieving glycemic control is the goal. ^(12)(13)(14)

For more information on exactly what to eat and what to avoid, check out this 2009 journal article that breaks down the glycemic index of more than 1,000 different kinds of food. 

3. Get an Adequate Amount of Sleep

While it can sometimes be difficult, making sure to get 7 - 9 hours of sleep each night is another way to support your immune system. Disordered sleep ultimately increases inflammation, which, in turn, impairs the ability of your body to appropriately monitor and respond to foreign viral invaders. ⁽¹⁵⁾

Getting an adequate amount of sleep helps to promote a more robust response of your Th1 helper cells, which again, play an important antiviral role in the immune system. ⁽¹⁶⁾

4. Get Regular Exercise/Stay Physically Active

Regular physical activity is vital to maintaining the proper function of all of the body’s main systems, including the immune system.  The unfortunate reality, however, is that many of us lead sedentary lives -- whether it’s at home, school or work, many of us spend the majority of our days sitting down.  

With a lack of physical activity built into many of our daily lives, inflammation can often build up, impinging the capabilities of our immune systems to optimally function.  However, numerous studies have demonstrated that regular exercise can help to decrease inflammation and bolster the immune system. ⁽¹⁷⁾

 It’s important to point out though that in order to potentially decrease your levels of inflammation, you have to be exercising at moderate intensity levels. ⁽¹⁸⁾ Exercising at too high of an intensity can actually increase the body’s release of pro-inflammatory cytokines, so things like exercise selection, intensity, and duration need to be taken into close consideration. ⁽¹⁹⁾

Immunity-Boosting Supplements and Substances

6. Vitamins C

Vitamin C is an essential nutrient that plays a vital role in several aspects of both the innate and adaptive immune responses.  Amongst other things, It’s especially important when it comes to maintaining the normal function of immune cells and also has a direct role in microbial killing. ^(20)(21)

A deficiency in vitamin C can ultimately decrease the responsiveness of your immune system, which may, in turn, increase your susceptibility to coronavirus.  In the instance that an infection does occur, vitamin C deficiency can impinge on your body’s ability to deal with the increased inflammation, which may result in a more severe disease trajectory. ⁽²²⁾

However, previous research on respiratory and systematic infections has demonstrated that vitamin C supplementation can have both preventative and therapeutic effects -- on top of decreasing the chances of becoming infected in the first place, vitamin C supplementation has also been shown to reduce the intensity and duration of infection. ⁽²³⁾

For instance, a 2019 meta-analysis examining thousands of Intensive Care Unit (ICU) patients ultimately found that those who were regularly given Vitamin C during their visits, on average, saw an 8.2% reduction in their ICU stay. ⁽²⁴⁾

7. Vitamin D

Vitamin D also has an important role in the immune system, aiding in the formation of lysosomal enzymes.  Within the immune system, lysosomal enzymes play an important part in the process through which macrophages actually kill off dangerous pathogens -- without lysosomal enzymes, macrophages wouldn’t be able to adequately function. ⁽²⁵⁾

Like with vitamin C, numerous studies have also demonstrated that vitamin D deficiency can impair immune function and induce excessive inflammation -- in fact, it’s been associated with a number of different autoimmune and inflammatory diseases. ⁽²⁶⁾

However, research shows that vitamin D supplementation can help to promote healthy macrophage function, helping the immune system to respond more effectively to infection, especially in individuals who have been shown to be deficient. ⁽²⁷⁾

8. Vitamin A

Vitamin A is central to the overall health of your immune system.  In fact, it’s commonly used as an indicator of your overall immune status.  Unfortunately, it’s estimated that over 30% of American adults don’t consume enough vitamin A in their daily diets. ⁽²⁸⁾

In addition to increasing inflammation, a deficiency in vitamin A can lead to several immunity impairments, including a decrease in helper T cells and a diminished antibody response.  Studies show that those who are vitamin A deficient are at a greater risk of contracting an infectious disease and ultimately have higher mortality rates. ⁽²⁹⁾

However, some research suggests that vitamin A supplementation may help to decrease inflammation, especially in deficient individuals. ⁽³⁰⁾ Furthermore, recent findings suggest that regular supplementation may improve recovery rates as well -- levels of vitamin A usually drop during an infection, which can lengthen the time course of the disease. ⁽³¹⁾

9. Zinc

Zinc is an essential mineral that is critical to the function of just about every cell in the immune system.  Amongst other things, zinc plays a critical role in the production of thymulin, an important nonapeptide hormone used by T cells. ⁽³²⁾

Zinc deficiency is especially common amongst older folks, with up to 50 percent of elderly adults lacking an adequate amount of zinc in their daily diets.   Even a slight deficiency can lead to an impaired immune response and a weakened resistance to viral infection, including COVID-19^{. (33)(34)}

However numerous studies have demonstrated that zinc supplementation helps to reduce the duration of infection, both in healthy individuals and those with deficiencies.  For example, one 2013 systematic review involving almost 20 different trials examined the effects of zinc on the common cold. 

The researchers ultimately found that when healthy individuals were administered zinc within 24 hours of their symptoms appearing, they recovered significantly faster in comparison to the control group. ⁽³⁵⁾

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10. Omega 3 Fish Oil

Omega 3 fish oil may also help when it comes to fighting off the coronavirus.  It contains the fatty acids EPA and DHA, which have been well established as anti-inflammatory agents.  Both EPA and DHA are precursors to pro-resolving lipid mediators, which play a central role in turning off the inflammatory process. ^(36)(37)

It’s important to point out though, that while omega 3s may be effective during the preventive stage, they may not be all that effective for addressing acute inflammation once an infection has occurred -- it’s mainly due to time scale issues. ⁽³⁸⁾

11. Propolis

Propolis is a resin-like substance derived from honeybees.  Its therapeutic properties have been known for over four thousand years and it continues to be used and studied in modern times due to its antiviral and antimicrobial properties. ^(39)(40)

In the immune system, propolis functions as a PAK1 blocker -- PAK1 is a pathogenic signaling agent within the body which research shows may be directly responsible for the onset of viral infections like COVID-19 when abnormally activated. ⁽⁴¹⁾

That’s because PAK1 has been shown to have suppressive effects on the immune system, reducing the body’s production of things like antibodies and other virus-fighting agents when overexpressed.  In addition to increasing your susceptibility to infection, an abnormally active PAK1 can also increase the severity and time course of an infection.  

However, propolis has actually been shown to inhibit the activation of PAK1, with a number of studies finding that propolis helped to boost immune system function in individuals with a host of different infections, including SARS, HIV, papillomavirus, and influenza. ⁽⁴²⁾

12. Melatonin  

Melatonin is a natural hormone that’s also been shown to bolster the immune system.  In addition to functioning as a PAK1 blocker -- again, research shows that irregular PAK1 activation may be responsible for the onset of viral infections --  there is also evidence that melatonin may serve other functions within the immune system as well. ⁽⁴³⁾

Findings suggest that melatonin supplementation may also help to bolster the immune response by improving antigen presentation in macrophages, as well as by enhancing the proliferation of natural killing cells -- processes which are both normally inhibited by the coronavirus. ⁽⁴⁴⁾

13. Quinine

Quinine is a naturally-derived compound extracted from the bark of the Cinchona tree.  It was first used as a malaria treatment back in the 17th century.  In modern times, chloroquine and hydroxychloroquine are both synthetic forms that were developed as substitutes and are now far more common than quinine itself. ⁽⁴⁵⁾

Like with propolis and melatonin, quinine has been found to inhibit PAK1 activation, which, in turn, has been shown to bolster the immune response.  While research examining the effects of chloroquine and hydroxychloroquine on coronavirus is still underway, other studies have demonstrated significant antiviral effects on other RNA viruses like influenza, poliovirus, rabies, and HIV. ⁽⁴⁶⁾

14.Curcuminoids

Curcuminoids are compounds derived from the turmeric plant and there is a sizeable body of evidence that some on them -- particularly curcumin -- have antiviral and anti-inflammatory properties. ⁽⁴⁷⁾

When it comes to the coronavirus in specific, recent research findings suggest that curcumin may help to prevent the entry of the SARS-CoV-2 virus into host cells by inhibiting viral replication, maturation, and spread. ⁽⁴⁸⁾

Another recent study also showed that curcumin helped to inhibit the virus from binding to ACE2 receptors -- it’s has been shown to attach to these receptors prior to entering into and infecting vulnerable cells. ⁽⁴⁹⁾

15. Echinacea

Echinacea is an extract derived from a plant of the same name and recent research suggests that it possesses potent antiviral properties.  On top of simply helping to prevent the spread of a virus, echinacea has actually been shown to help destroy it altogether, which is why it’s sometimes referred to as a virucide.    

More specifically, research shows that echinacea helps to deactivate membrane containing viruses like COVID-19 through breaking down the virus’ membrane components and inhibiting replication. ⁽⁵⁰⁾

In addition, other findings also suggest it has anti-inflammatory effects as well, helping to prevent an inflammatory response in epithelial cells, which normally become inflamed as a result of a viral infection. ⁽⁵¹⁾

16. Licorice Root (Glycyrrhiza glabra)

Licorice root, which is also known as glycyrrhiza glabra, is a herbal extract commonly used in the treatment of viral infections in both eastern and western medicine.  In fact, it comprised a major part of the formulas that were eventually developed to treat and prevent the SARS and H1N1 viruses. ⁽⁵²⁾

That’s because numerous clinical trials have demonstrated it effectiveness in bolstering the immune response in the presence of viral invaders.  In particular, research shows that licorice root plays an important role in the production and proliferation of Th1 cells, which helps to coordinate and initiate the immune response. ⁽⁵³⁾

Wrap Up

There you have it, 16 different ways in which you can improve the function of your immune system in the midst of coronavirus. 

From healthy lifestyle practices like eating a well-balanced diet and minimizing stress to taking immunity-boosting supplements and substance, research shows that there are a number of ways to potentially decrease your susceptibility to the virus.  

While these practices may not make you totally immune to COVID-19, they can help to better prepare your body to deal with the virus, so in the event that you do become infected, your immune system is ready to respond robustly. 

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