Building A Resilient Immune System

Now that we are many months into the COVID-19 pandemic and navigating next steps on a lot of levels, one thing is clear: this is a marathon and not a sprint.

With our response to this pandemic, we came together and took the slow way through, by sheltering in place and flattening the curve.

As a culture we are always looking for the quick fix. We want to lose the 10 pounds in 10 days, we want a pill to “fix” our health problem and we certainly want COVID-19 to be over so we can go back to work, school, vacations and the daily grind. 

While we wait for more solutions from the government and medical community, more people are turning toward supplements to boost the immune system.

But, in the face of SARS-CoV-2, the virus that causes COVID-19, does the immune system really need a one-time boost? Is that the best strategy right now, and for future viruses that we are sure to be exposed to? 

This terminology and mindset about immunity stems from the same cultural need for an easy, and most importantly, quick fix to the situation. 

Believe me, I’ve used the term “boost” before – it grabs your attention, right? But I’d like to talk today about a different way to think about supporting the immune system: building immune system resilience.

This is the longer road, but also the one worth taking for long-term health and well-being. 

In this article, you’ll learn more about:

  • What is immune system resilience?
  • My top tips for building immune resilience

Let’s dive in!

Immunity And Resilience

Resilience is the process that allows you to adapt to an adverse condition or stress, recover and return to homeostasis, or balance.

There are certain qualities – such as a positive outlook, coping tools and social support – that promote psychological resilience. Interestingly, people with more resilience tend to also be the same people who have more robust immune systems. And the connection goes the other way too. A strong immune system promotes resilience in other aspects of life and health. 

In a 2018 article in Brain, Behavior and Immunity, authors describe how resilient people have a different “immunophenotype” – meaning the way that specific immune genes are expressed – vs. those who are more prone to stress and inflammation. Note: this has everything to do with epigenetics!

We aren’t looking at the genes themselves, but the environmental factors – think sleep, nutrition, toxins, etc. that influence what genes get turned on or off. Excitingly, this means we have the ability to strengthen our resiliency by modifying how we think and behave!

An example of these connections that we’ve been discussing is depression. In depression, there is a loss of resilience to the stresses and toxic exposures of life. What’s interesting is that those with major depressive disorder also have an increased rate of inflammatory disease, suggesting that the immune system is playing a role.

Anti-inflammatory treatments are a new area of research for depression, as managing inflammation seems to promote better resilience. 

Of note, those with inflammatory conditions including diabetes and heart disease are more at risk for severe outcomes with COVID-19. The immune system is already shifted towards inflammation and then the disease pushes inflammation even more. 

When it comes to the immune system’s resilience, what’s crucial is having the appropriate response. This means having a big enough response when stimulated by something foreign, like a virus, but also having no response and remaining passive to things that don’t pose a threat, like a food or pollen for example.

An over responsive immune system, might mean environmental allergies, food allergies or autoimmunity. We don’t want too little immune response, or too much, but just what’s appropriate.  It’s this sweet spot that we best cultivate resilience. 

How To Build A Resilient Immune System

Dr. Jeff Bland, the founder of Functional Medicine, talks about how your immune system is your superpower. It truly is; it plays a role in all aspects of life and health and keeps you safe, balanced and strong throughout whatever life brings. 

If your immune system isn’t as resilient as you like or if it is strong and you want to keep it that way, instead of focusing on one-time ways to “boost” its function, consider daily lifestyle practices that rewire immunity and build resilience over time.

Here’s how:

  • Balance your biome. The microbiome is a key factor in building immune resilience and an imbalance is associated with developing inappropriate immune responses. Gut issues are often one of the root causes to symptoms and disease, including immune diseases that my patients come to me for. In my practice, I use the GI MAP stool test as one tool to assess the balance of the microbiome, digestive function and diagnosis of any pathogenic infections. With these results, we then personalize a 5R Gut Healing Protocol, often including specific antimicrobials, digestive support, probiotics and dietary strategies. By restoring gut health and microbial balance, we go beyond boosting the immune system to foster the foundation for resilient immunity. 


  • Reduce toxin exposures. This is a big project and one that can be done in small steps, over time. Begin by replacing personal care and cleaning products, then move to filtering your home air and water and ultimately educating yourself about environmental toxins and how to protect your living and work space from over exposures. By reducing these exposures that you can control, you lower the total toxin burden on the body, which lowers stress and inflammation. If the immune system is constantly working on mounting a defense to toxic invaders, over time this impacts resilience. 


  • The best way to stay up to date and new information about environmental toxins is by joining my email list and you’ll receive my free report: How to Be Safe in a Toxic World. I’m constantly looking at the latest information to bring to you, along with practical lifestyle solutions.


  • Adopt an anti-inflammatory diet. Many of the fiber-rich colorful foods that help to feed a healthy microbiome, are also antioxidant rich and anti-inflammatory. Since inflammation is a concern with COVID-19, nutrition is such a powerful tool for lowering baseline inflammation in the body and therefore, supporting immunity. I’m not referring to a one time recipe of exotic greens or a shot of ginger turmeric juice, but day-in and day-out diet choices you make that profoundly impact your health and resilience. I often recommend starting with a Paleo diet template, rich in nutrient-dense whole foods and low in inflammatory foods and then personalizing from there. 


  • Optimize your vitamin D levels. Vitamin D is often thought of in terms of bone health, but it is also critically important for the immune system to be able to do its job. Some preliminary research makes the link between low vitamin D levels and the severity of COVID-19 outcomes. The standard vitamin D recommendations (600IU per day) are woefully low for maintaining optimal blood levels between 50 and 80 ng/mL, the recommended levels for prevention of COVID-19 infection and complications. 


The best course of action is to have your vitamin D levels checked every year and adjust supplementation accordingly. In absence of testing, the Institute for Functional Medicine recommends supplementing 5000 IU per day

For more information on specific nutrients and botanicals for the prevention and treatment of COVID-19, see the Institute for Functional Medicine’s recommendations here. And, for my personally vetted, high quality product recommendations go here

Prioritize Quality Sleep

Even one night of poor sleep produces changes to the immune system the next day, and when poor sleep is chronic it suppresses immunity and increases inflammation. This goes hand in hand with stress: poor sleep increases stress and decreases immunity.

You’ve likely made this connection for yourself already. Do you ever feel less resilient in your day after a poor night’s sleep or that you’re bound to get sick when stress is high and sleep is poor? 

For many of us, improving sleep comes down to committing to a bedtime. Start by developing a relaxing evening routine and limiting screens. Both exercise and stress management during the day helps with sleep at night. Your body does the most healing while you are in deep sleep, so to build immune system resiliency start improving your quality of sleep immediately. 

The tips that I’ve discussed here for supporting resilience are the same lifestyle factors that help you to maintain a healthy weight, express your best genetics and prevent chronic immune system disease. 

Ultimately, there is rarely a quick fix or one easy solution to any complex problem. That’s why I love being a Functional Medicine doctor so much! I get to be a health detective and help you uncover the pieces to your unique puzzle.

By addressing the root, instead of simply applying a band-aid to your health concerns, you’ll build a solid foundation to health and increase your resiliency. 

So, I challenge you, the next time you think about a boost or a quick fix, go down one more layer and think about all of these components to your health story and immunity. Just like you can rewire your brain for new habits, you can rewire your immune system too. It may be a bit more effort, but it’s worth the effort to have long-lasting health. 


  1. Dantzer, R., Cohen, S., Russo, S. J., & Dinan, T. G. (2018). Resilience and immunity. Brain, behavior, and immunity, 74, 28–42. 
  2. Ménard, C., Pfau, M. L., Hodes, G. E., & Russo, S. J. (2017). Immune and Neuroendocrine Mechanisms of Stress Vulnerability and Resilience. Neuropsychopharmacology : official publication of the American College of Neuropsychopharmacology, 42(1), 62–80. 
  3. Guo, W., Li, M., Dong, Y., Zhou, H., Zhang, Z., Tian, C., Qin, R., Wang, H., Shen, Y., Du, K., Zhao, L., Fan, H., Luo, S., & Hu, D. (2020). Diabetes is a risk factor for the progression and prognosis of COVID-19. Diabetes/metabolism research and reviews, e3319. Advance online publication. 
  4. Li, B., Yang, J., Zhao, F., Zhi, L., Wang, X., Liu, L., Bi, Z., & Zhao, Y. (2020). Prevalence and impact of cardiovascular metabolic diseases on COVID-19 in China. Clinical research in cardiology : official journal of the German Cardiac Society, 109(5), 531–538. 
  5. Shi, N., Li, N., Duan, X., & Niu, H. (2017). Interaction between the gut microbiome and mucosal immune system. Military Medical Research, 4, 14. 
  6. Zabetakis, I., Lordan, R., Norton, C., & Tsoupras, A. (2020). COVID-19: The Inflammation Link and the Role of Nutrition in Potential Mitigation. Nutrients, 12(5), E1466. 
  7. D’Avolio, A., Avataneo, V., Manca, A., Cusato, J., De Nicolò, A., Lucchini, R., Keller, F., & Cantù, M. (2020). 25-Hydroxyvitamin D Concentrations Are Lower in Patients with Positive PCR for SARS-CoV-2. Nutrients, 12(5), E1359. 
  8. The Institute for Functional Medicine. The Functional Medicine Approach to COVID-19: Additional Research on Nutraceuticals and Botanicals. Accessed 5/28/20.
  9. Watson, N. F., Buchwald, D., Delrow, J. J., Altemeier, W. A., Vitiello, M. V., Pack, A. I., Bamshad, M., Noonan, C., & Gharib, S. A. (2017). Transcriptional Signatures of Sleep Duration Discordance in Monozygotic Twins. Sleep, 40(1), zsw019.