Using Foods to Balance the Immune System and Optimize Function

In response to the COVID-19 pandemic, a lot of sources have focused on how to boost the immune system. I think that it’s a faulty premise to look at it that way. Suffice it to say, you want to face this infection with an immune system that is well-balanced and poised to respond appropriately. It shouldn’t necessarily be ramped up in general. Theoretically speaking, that could in fact be very disadvantageous. Our immune system is a single entity just the same way as Homeland Security is one force. That is to say, not at all. It’s a complex interplay of various extremely specialized and highly interdependent systems.  Just like Homeland Security has many specialized divisions like FEMA, the Coast Guard, the Secret Service, etc. So to say we’re going to boost “the immune system” is like saying we’re going to give more ships to the Department of Homeland Security. If we are talking about giving them to the Coast Guard that makes sense. If we’re talking the Border Patrol, then not so much!

So, what do we mean by a well-balanced immune system? What we mean here is a situation that removes the distractions and allows the immune system to do what it does best; surveillance for pathogens and responding appropriately to eliminate them (without causing collateral damage!). In other words, what we must avoid are a lot of distracting issues that the immune system is pre-occupied with fighting that results in the infection slipping through undetected. It’s akin to trying to fight a war on two fronts. How do we make sure that’s the case? It all comes down to managing inflammation. At it’s root, the word inflammation means going up in flames. Not good! The result of that is usually a number of well described phenomena dating back to time of the classic physicians who described it in Latin words such as dolor, rubor, calor, tumor which translate as pain, redness, warmth and swelling. Plus there’s an additional one which is loss of function. So if you’re experienced any of those, it’s a sign of inflammation. When you sprain your ankle, or maybe had an infection somewhere, those are the results of inflammation. But inflammation can also manifest in less obvious ways than a swollen body part. It can happen silently inside the body. People that have pain and bloating after meals likely have inflammation. Obesity itself is an inflammatory condition. So there are many sources. That’s in essence what we do in Functional Medicine. In a way we are “Inflammologists.” We look for hidden, and not so hidden, sources of inflammation and find strategies to minimize the effects.

One of the biggest sources of hidden inflammation comes from our diet. This is very unfortunate and comes mainly from what we term the “SAD” diet, which stands for standard American diet. This diet comprised of highly processed and refined food products, often devoid of essential nutrients and plant-based cytoprotective compounds is highly pro-inflammatory. We can actually prime our immune system to respond with an overly active inflammatory response just by the foods we eat. How? We need to change our diet to one that consists of highly nutritious, brightly colored vegetables and fruits. Why do I mention “brightly colored?” For a very good reason! When you are exposed to intense sunlight for too long you may become sunburned. Red, sore, swollen skin. Inflammation, right? Plants are out in the sun all day long. They can’t put on sunscreen or go inside. Therefore they have highly evolved anti-inflammatory and anti-oxidant systems. Most of those are compounds which impart the pigment of color to the plant or it’s fruits. When you ingest the plant, your body is also benefitting from those plant-based compounds. They are anti-inflammatory for you and prevent oxidation, which is the same as rust on metal, but a similar undesirable process occurs inside the body.

What’s that mean in a nutshell? And, yes some nuts also contain beneficial compounds, so pun is intended! Here are my specific recommendations, based on my knowledge and agreed upon by experts in the field:

  • Eat plenty of fruits and vegetables. Aim for 9-13 servings per day of a variety of colors. Each color is a different one of those beneficial plant-based “phytonutrients” which will offer protection to cells and enhance the balance of beneficial microbes in the GI tract.
  • Flavinoids are a special variety of plant-based phytonutrients that contain some specifically anti-viral compounds such as:
    • Kaempferol (spinach, cabbage, and dill)
    • Quercetin (dill, onion, oregano, chili pepper, apples, leafy green vegetables, broccoli)
    • Hesperidin (oranges, grapefruit, lemon, tangerines)
    • Oleuropein (olives and extra virgin olive oil)
    • Catechins and epicatechin gallate (green tea)
    • Lauric acid (unrefined virgin coconut oil)
  • There are many anti-viral and immune supporting herbs and spices. In their day, these spices were not just to enhance the flavor of foods, but they were the worlds first dietary supplements to support health and wellbeing. Some examples of these are:
    • Ginger
    • Garlic
    • Turmeric
    • Rosemary
    • Chili pepper
    • Oregano
  • Consume a minimum of 25-35 grams of beneficial pre-biotic fiber daily, preferably from whole foods. Prebiotic foods include: Dandelion greens, Jerusalem artichokes, garlic, onions, leeks, asparagus, artichokes, bananas, apples, konjac root (shirataki noodles), cocoa, burdock root, flax seeds, jicama root, and seaweed.
  • Eat fermented vegetables and other probiotic-containing foods to improve barrier function in the GI tract and help to minimize hidden inflammation. The microbiome is crucial for regulating inflammation and most of us no longer have a robust and diverse population of health-promoting microbes. Those challenged by chronic diseases are even in worse shape. Consider grass-fed sheep, cow, or coconut yogurt, kefir, sauerkraut, tempeh, miso, natto, kimchi, and pickles.
  • Reduce or avoid food products which provoke inflammation such as added sugars and salt, high-glycemic foods such as processed-carbohydrates, and excessive saturated fat.
  • Severely curtail or entirely stop alcohol as it may directly suppress immune defenses and depletes key nutrients.
  • Consume an adequate amount of protein which is crucial for proper immune function. Protein malnutrition is more common in elderly and vegan populations. Most other populations already eat adequate protein. You need at least 1 gram/kg of body weight, or about one-half your body weight in pounds. Look for a complete source of amino acid content from the protein you consume. This is not an issue for meat eaters, but is essential for vegans.

This the first in a series of articles on lifestyle factors which serve as important interventions to improve the host response to this viral threat. The reason I placed this article here first is because it’s the most important. It starts with food. Honestly, for most people out there, just taking the above measures would be the healthiest, safest and most effective way to shore up their defenses against the SARS-CoV-2 virus. This could play out as making the difference between an asymptomatic infection/minimal cold symptoms, versus a more severe course that lays them out in bed for several days or even worse ending up in the hospital. My goal personally is to try to make exposure and subsequent response to this virus a non-event. Which it should be for healthy people. I work in a very high-risk environment, so I am continuously exposed to the sickest of these patients. They are shedding incredible amounts of virus at that stage of their illness. I will very likely become infected. But the goal is to meet that infection with strong and balanced defenses in order to prevent a severe course of illness. For more background see my other article on a Functional Medicine Approach to COVID-19. The next article will focus on other lifestyle factors such as sleep, stress reduction, exercise and social factors. Stay tuned!

I would like to thank the leaders in the field of functional medicine for providing a catalyst for the material I included in this post. Specifically, Dr. Mark Hyman who I consider one of the foremost spokespersons and leaders for functional medicine, as well as the Institute for Functional Medicine which provided incredibly well-researched and referenced summaries and documents I will link to below.

  1. "A Functional Medicine Approach to COVID-19" by Dr. Mark Hyman.
  2. "Lifestyle Practices for Strengthening Host Defense" by the Institute for Functional Medicine.
About the author

A medical doctor who will "Look Deeper" to help everyone achieve their "Peak Health"

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