Studies estimate that 97-98% of people living in the United States are deficient in certain vital micronutrients.[1]
The reality of modern-day society is that you’ve got a lot of factors working against you. Malnourished soil, the cost of whole foods, and even personal stress are all contributors to nutrient depletion. Even under the best of circumstances, nutrient deficiencies are quite common in people today. You could eat a diet full of supposed nutrient-dense foods, yet still be deficient in key nutrients due to environmental factors.
However, there are steps you can take to both prevent deficiencies and support a healthy immune system.
First, it’s necessary to have a general understanding of how the immune system works and what role nutrients play in the first place.
The immune system’s first line of defense against potential pathogens and invaders is called the physical barrier. Your skin is a physical barrier along with your mouth, the lining of the esophagus, and the stomach lining, lungs, and intestines. Part of these physical barriers include secretions that play crucial roles in the immune system, like stomach acid.
When invaders are able to pass through these physical barriers, they enter the systemic immune system. They face immune cells like CD4, CD8, and MK (aka natural killer) cells, along with cytokine mediators processes.
Research shows that suboptimal nutrition and immune health go hand in hand, and there are many opportunities within all of these immune system layers where nutrient deficiencies can cause impairments and compromised function.[2]
While various factors can contribute to nutrient depletion and deficiencies, these four are generally the most common and can lay the foundation for a poor inflammatory response.
The way you preserve and store foods can have a significant impact on their nutritional content.
Fresh foods that come from local sources have the highest nutritional content, and the next best options are frozen foods. Canned foods usually have the fewest nutrients, although many factors play into how well foods maintain or lose their nutrients, such as refrigeration, and organic versus conventional produce. This review from the University of California, Davis, has more information about maximizing the nutritional value of fruits and vegetables.
How you cook your food also plays a role.[3] Steaming is an excellent way to preserve nutrients in foods, followed by roasting and baking. Stir-frying on low to medium heat in a healthy cooking oil - like avocado, coconut oil, or butter - is an effective method that helps the body absorb fat-soluble vitamins. Avoid cooking using high heat, like grilling and frying as often as possible. Heat-sensitive nutrients like omega-3 fatty acids can be damaged at high temperatures.
A 2018 study found that 66% of all American adults were taking medication, many of which can inhibit the absorption of minerals and other nutrients.[4] Over-the-counter meds can have a similar effect, and the list of those that impact nutrient stores and absorption is a long one.[5] If you’re concerned that a medication might be impacting your nutrition and health, talk with your doctor.
It’s no secret that chemical farming and modern-day industrialized agricultural practices are wreaking havoc on the mineral content of soil and the foods we eat.* Studies show a dramatic decline in key vitamins, minerals, and other nutrients in both soil and produce, which is largely a result of chemical-based agriculture and over-farming.[6] This is one reason why buying organic versus conventional produce whenever possible, is a good idea; it yields more nutrient-rich foods.
Stress is a leading cause of systemic inflammation, which can decrease your micronutrient levels. An overly scheduled daily routine and high-stress levels tend to lead to poor food choices, less sleep, inadequate hydration, and increased inflammation. All factors can inhibit immune function and decrease nutrient stores.[7]
While a balanced and varied diet will help cover all of your nutrient bases and support immune health, certain nutrients are especially important, specifically vitamins A, C, D, E, B12 and B6, folate, iron, and zinc, omega 3 fatty acids, and CoQ10.*
Vitamin A is essential for the lining of the gut and plays an essential role in T and B cell function.* Vitamin D is also critical, as it creates a healthy composition of intestinal cells.* In general, it’s important to remember that gut health is foundational for a healthy immune system.
Vitamin E is a potent antioxidant that works to protect against free-radical damage, and vitamins B12, B6, and folate support multiple biochemical immune system reactions.* Iron is crucial for growth and differentiation of the epithelial cells, while zinc provides skin and mucosal membrane integrity, among other functions.* Omega-3 fatty acids and CoQ10 have a significant impact on inflammation, gut health, and immune function.*
Without many of these vital nutrients for immune function, the body isn’t able to respond as it should to attacks. Insufficient vitamin D can lead to increased inflammatory cytokines, which could contribute to certain autoimmune challenges.[8] Without enough vitamin A, your T-cells and B-cells become unregulated, which decreases immune function and leaves you more susceptible to catching a bug from a handshake, nearby sneeze, or other contagions that may not be a problem otherwise.
Nutrient inadequacies suppress the immune system, while optimal nutrient levels strengthen it by boosting your immune system, maintaining a strong intestinal lining and microbiome and increasing your resilience.*
First and foremost, opt for local, organic whole foods as often as possible, and leave processed foods on the shelf. For example, choose actual chicken over a chicken nugget, steak over a hot dog, and an apple over applesauce.
Second, consider nutritional supplements based on personal needs. Keep in mind that soil degradation can make it challenging to meet your nutrient needs through foods alone, even with organic foods.
You might consider working with an integrative or functional medicine doctor to analyze your medical history, diet and lifestyle for nutritional gaps that might be impacting your immune function.
A healthy immune system depends on a nutritious diet – and supplementation when necessary – stress management, self-care, and physical activity. There will always be environmental factors that put stress on our immune health, so it's a good idea to focus on aspects you can control.
Try to choose a few lifestyle changes that will support long term wellness. Your body will thank you for it!
*These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure or prevent any disease.
[1] https://lpi.oregonstate.edu/mic/micronutrient-inadequacies/overview
[2] Maggini, S., Pierre, A., & Calder, P. C. (2018). Immune Function and Micronutrient Requirements Change over the Life Course. Nutrients, 10(10), 1531. https://doi.org/10.3390/nu10101531
[3] https://www.ars.usda.gov/ARSUserFiles/80400525/Data/retn/retn06.pdf
[4] https://hpi.georgetown.edu/rxdrugs/
[5] Mohn, E. S., Kern, H. J., Saltzman, E., Mitmesser, S. H., & McKay, D. L. (2018). Evidence of Drug-Nutrient Interactions with Chronic Use of Commonly Prescribed Medications: An Update. Pharmaceutics, 10(1), 36. https://doi.org/10.3390/pharmaceutics10010036
[6] https://soils.wisc.edu/facstaff/barak/poster_gallery/minneapolis2000a/
[7] Lopresti AL. The Effects of Psychological and Environmental Stress on Micronutrient Concentrations in the Body: A Review of the Evidence. Adv Nutr. 2020;11(1):103‐112. doi:10.1093/advances/nmz082
[8] Liu, W., Zhang, L., Xu, H. J., Li, Y., Hu, C. M., Yang, J. Y., & Sun, M. Y. (2018). The Anti-Inflammatory Effects of Vitamin D in Tumorigenesis. International journal of molecular sciences, 19(9), 2736. https://doi.org/10.3390/ijms19092736