Nutrition For Immune Health
As we continue to learn more about COVID-19, it is increasingly clear that the health of the host is paramount. It’s easy to get caught up in the media coverage of the search for a cure or a vaccine, which has a place; but I encourage you to take every action you can, right now, to improve your immune system to fight this infection.
Let’s not underestimate the power of foundational health support. I’m talking about good sleep, stress management, exercise and, of course, solid nutrition. Once the foundations are in place, I also believe implementing key supplements can help boost the immune system.
Today I want to focus more on the nutrition piece of this prevention pie. Food is powerful medicine, especially when high quality foods are consumed consistently, day after day.
You build a foundation of health, support the immune system, lower inflammation, build optimal nutrient status and ward of chronic disease.
In this article, I’m going to talk more about:
- How the immune system functions
- Inflammation, immunity and the role of nutrition
- My top tips for using diet to cool inflammation
Understanding The Immune System
Your immune system helps you to survive every day. It must be constantly alert and be able to distinguish your own cells from invaders. The innate immune system acts like the first responders when a pathogen is detected.
The innate immune system, that includes different immune cells such as macrophages and neutrophils, responds to the scene fast, but it’s not very specific.
The adaptive immune response, is more specific to a particular pathogen, but takes a little more time to mount a defense. It’s job is to create antibodies in order to quickly identify an invader, should it be exposed again.
Main players in adaptive immunity include B cells that produce antibodies and T cells that recognize antigens and help to communicate and coordinate an appropriate immune response.
All of this happens without you having to think about it… This is your body working for you.
However, for a well-functioning immune system, just like every system in the body, immunity requires nutrition. Vitamins, minerals, amino acids and other compounds, often in continuous supply, are critical.
This is why you’re constantly hearing about vitamin D, vitamin C and other nutrients in regard to COVID-19.
Nutrition builds the structure of the immune system and is required for its function. If a pathogen invades, such as the SARS-CoV-2 virus that causes COVID-19, you want your immune system to be primed and ready to take action. Nutrition helps with this.
Inflammation And How Diet Affects The Immune System
In addition to providing the physical structure and optimal function of the immune system, another way that diet impacts immunity has to do with inflammation.
Inflammation is an immune process designed to heal damage. If you get a cut or step on a nail, the immune system delivers pain, redness, swelling and immune cells to repair the damage and protect you from infections. In this acute scenario, inflammation reduces when the job is done.
With chronic inflammation, there are simmering levels of inflammation throughout the body that never reduced to a safe level. Chronic inflammation is an underlying driver of chronic disease and is related to diabetes, heart disease, autoimmune disease, and many other health conditions and diseases..
Inflammation is of particular concern with COVID-19. As the disease progresses, inflammation dramatically increases and may possibly overwhelm the system. Perhaps you’ve heard the term “cytokine storm” in this context. Cytokines are inflammatory messengers produced by cells.
We know that those with pre-existing conditions, including the same chronic disease related to inflammation, are at a higher risk for severe complications and death from COVID-19. In a study of 5700 New York City patients hospitalized with COVID-19, 88% had at least two chronic health conditions.
Because of this inflammatory connection, one goal of prevention and treatment of COVID-19 (not to mention the prevention and treatment of chronic disease) is to reduce inflammation. Diet is a powerful tool for reducing inflammation.
The traditional Western diet is inherently inflammatory. There’s a reason the Standard American Diet is deemed SAD. Processed food, convenience items, vegetable oils, added sugars, artificial sweeteners, high fructose corn syrup, food additives and chemicals (toxins) in food all contribute to inflammation. Because for many, this becomes the bulk of the diet, which means missing out on the nutrient-dense foods the body needs.
It is also well known that those with inadequate nutrition, often in developing nations where food is scarce, have weakened immunity. Here, we tend to have plenty of calories, but lack the nutrition to fully meet the body’s needs for each nutrient.
In addition, diet profoundly impacts the gut microbiome, which is another way immunity is modulated. An imbalance in the microbiome, or infections, contribute to inflammation.
If you think about it, the bacteria and other organisms that make up the microbiome, often come into contact with pathogens before they enter the body. Given this, it makes sense that the majority of our immune system (around 75%) is located in the digestive tract.
Because of these connections, improvements in the diet are strongly associated with the reduction of inflammation. Let’s talk about how to do that.
How To Boost The Immune System With Food – Dr. Shippy’s Top Tips
If you are curious about how to boost the immune system naturally, food is a great place to start. Instead of giving the immune system a one time “boost,” diet really creates an immune foundation to last a lifetime. The immune system retrains itself to become less inflammatory all of the time, so it can function optimally when needed most.
Try these action steps:
1. Adopt a Paleo diet. If you’ve been following me for a while, you know what a fan I am of this nutrient-dense, ancestral style of eating. It is highly customizable for each individual’s needs and goals, plus it naturally includes anti-inflammatory foods and minimizes the most inflammatory offenders including refined sugars, highly processed oils, gluten (link to gluten article) and dairy.
2. Don’t skimp on the plant foods. One myth about a Paleo diet is that it includes mostly meat. A well balanced Paleo diet does include high quality animal protein; however, the majority of each meal is actually plants (at least 50% from vegetables, preferably cruiferous).. Colorful plant foods provide vitamins, minerals and an abundance of phytonutrients, many of which act as antioxidants in the body to stop inflammation from damaging cells. In addition, because of all the toxins we are exposed to, lots of daily antioxidants support the body’s natural detoxification process, and are so important for immune health and overall wellness.
Try to eat a variety of colors each day:
- Green – kale, lettuce, broccoli, cilantro, thyme, avocado
- Red – beets, strawberries, red carrots, pomegranate
- Orange – sweet potatoes, carrots, orange peppers, turmeric
- Yellow and white – summer squash, onions, garlic, cauliflower, ginger
- Purple – purple cabbage, blueberries, blackberries
- Brown – walnuts, pecans, spices
These are some of my favorite anti-inflammatory foods!
3. Balance blood sugar. Balancing blood sugar is one of the most important things you can do to cool inflammation. Insulin resistance and high blood sugar is associated with inflammation. We know that those with diabetes have more severe symptoms with many infections.
The Paleo diet naturally removes the processed grains that can spike blood sugar and adds in more fiber-rich plant foods that help to balance it after meals. In addition, try these tips to balance blood sugar.
- Find your sweet spot with carbs. While a Paleo diet is often moderate in carbohydrates, it can also be higher than some people tolerate because of the starchy vegetables, fruits and natural sweeteners. If you have insulin resistance, metabolic syndrome or diabetes, it is worth experimenting with your carb tolerance and adjusting your diet accordingly. If you decrease carbs, you may need to add a little more fat to meals to help with satiety.
- Eat protein with each meal and snack. This means, don’t eat carbs alone – even healthy ones like veggies. By pairing with protein (and ideally healthy fat like olive oil and avocados), you’ll help to balance your blood sugar after meals and last longer before hunger sets in again.
4. Balance your omegas. While omega-3 fats tend to be more anti-inflammatory and omega-6s more pro-inflammatory, the majority of us get too many omega-6s and not enough of the 3s. This imbalance goes hand in hand with a more processed, packaged and SAD diet.
Omega-6 fats are naturally found in chicken, nuts and other whole foods. We get enough from these sources without having to think about it too much. Where we get into trouble is with the processed, inflammatory vegetable oils. Think corn oil, soy oil, canola oil, sunflower oil, safflower oil and the like. These are often found in processed foods, so by decreasing these in favor of whole foods you naturally work on improving your ratio.
Omega-3 fats are the ones to work on increasing. Sustainable, cold water fish are the best source. Try wild salmon, wild cod, mackerel, sardines and anchovies. Shoot for three servings per week and you may even want to add in a high quality fish oil supplement to ensure your needs are met and help reduce inflammation.
Although I believe diet should always be at the top of our radar when it comes to health, for many COVID-19 has been the driver for taking steps to put a more anti-inflammatory diet in place.
I’ve noticed that my patients and people in my community have been forced to cook more at home… and are loving it!
They are noticing the health benefits of getting back into the kitchen, cooking meals using whole food ingredients and creating new habits around slowing down with food.
I wholeheartedly agree with this health strategy; it reduces inflammation, builds nutrition and provides an important piece to self-care and the health foundation that allows us to feel safe and confident, no matter what virus is going around.
- Childs, C. E., Calder, P. C., & Miles, E. A. (2019). Diet and Immune Function. Nutrients, 11(8), 1933.
- Tay, M. Z., Poh, C. M., Rénia, L., MacAry, P. A., & Ng, L. (2020). The trinity of COVID-19: immunity, inflammation and intervention. Nature reviews. Immunology, 1–12. Advance online publication.
- Richardson, S., Hirsch, J. S., Narasimhan, M., Crawford, J. M., McGinn, T., Davidson, K. W., and the Northwell COVID-19 Research Consortium, Barnaby, D. P., Becker, L. B., Chelico, J. D., Cohen, S. L., Cookingham, J., Coppa, K., Diefenbach, M. A., Dominello, A. J., Duer-Hefele, J., Falzon, L., Gitlin, J., Hajizadeh, N., Harvin, T. G., … Zanos, T. P. (2020). Presenting Characteristics, Comorbidities, and Outcomes Among 5700 Patients Hospitalized With COVID-19 in the New York City Area. JAMA, e206775. Advance online publication.
- Christ, A., Lauterbach, M., & Latz, E. (2019). Western Diet and the Immune System: An Inflammatory Connection. Immunity, 51(5), 794–811.
- Clements, S. J., & R Carding, S. (2018). Diet, the intestinal microbiota, and immune health in aging. Critical reviews in food science and nutrition, 58(4), 651–661. https://doi.org/10.1080/10408398.2016.1211086
- Yanuck, S.F., Pizzorno, J., Messier, H., & Fitzgerald, K. Evidence Supporting a Phased Immuno-physiological Approach to COVID-19 From Prevention Through Recovery. Integrative Medicine, 19(S1), Epub ahead of print.