immune system

Your magnificent immune system defends your body against potentially infectious agents such as bacteria, viruses, fungi, and parasites. It also sets your body’s baseline inflammation levels. The wide ranging benefits granted by your immune system include defense against cancer, heart disease, allergies, and autoimmune diseases.

Innate & Adaptive

Our immune system is split into two basic parts: the innate and the adaptive:

  • The innate immune system is a generalized set of defenses that act quickly to protect the body from invaders in the same basic way regardless of the specifics of the invader.
  • The adaptive immune system is the invader-specific set of defenses developed over time. Your adaptive immune system creates antibodies in response to specific invaders—which is also what a vaccine provides.

8 proactive measures you can take right now

The following strategies apply mostly to your innate immune system since they do not address any one specific invader. Instead they can improve your generalized response to anything you might encounter out in the world. These 8 proactive measures help support your best possible immune system function:

  • Sleep: There is no replacement for high quality sleep. Among the first responders to an infection, “T Cell” function is improved by getting optimal sleep1. Sleep directly affects stress hormones in your body. Chronic sleep loss increases stress markers and results in immunodeficiency. A 2009 study showed that participants with less than 7 hours of sleep were almost 3 times as likely to catch the common cold as those with 8 or more hours of sleep2.
  • Exercise: Aside from a short-term suppression of immune system function with very high intensity exercise, all types of regular physical activity decrease the risk of infection3.
  • Diet: The wide spectrum of vitamins and minerals found in whole foods helps increase immune system function and prevent infections. The bottom line with diet is vegetables, vegetables, vegetables4.
  • Vitamin C: Supplemental Vitamin C taken on a daily basis reduces your risk of infection. Used up by your body at a faster rate when you are infected, Vitamin C works by enhancing your immune system’s ability to kill invaders. It also functions as an antioxidant against the infection-clearing inflammation created by the immune system, decreasing collateral tissue damage5.
  • Zinc: Similarly to vitamin C, zinc can mitigate excess inflammation when your body is fighting an infection. It also improves immune system function by helping decrease the risk of a variety of infections6,7.
  • Quercetin: Especially in the spring, Quercetin is a great, doubly-beneficial compound to take. It reduces allergy-related symptoms along with helping to defend against viral infections. Quercetin improves the balance of your immune system, finding the “goldilocks zone” of just the right amount of inflammation8. As mentioned in an earlier article, quercetin specifically has an ionophore role with zinc, increasing zinc’s effectiveness in clearing infections9.
  • Mushrooms: A large range of medicinal mushrooms have been shown to enhance antiviral defenses along with the inflammatory response to any invader. Reishi, shitake, cordyceps, agaricus and others have all shown varying levels of immune system stimulation that improves the immune cells’ response time to an invader and the power of their response10. Essentially, mushrooms teach your innate immune system how to be more effective and efficient (which is likely where their anticancer effects also lie).
  • Heat and Cold Exposure: Various methods of heat and/or cold exposure are easy ways to boost your body’s defenses. Regular sauna use increases your white blood cell count and decreases your risk of the common cold and other respiratory illness11. On the other end of the spectrum, short term (1-3 minutes) cold water exposure increases immune system activity12. The simplest way to integrate this into your daily routine is to end your normal hot shower with a minute of cold water!

Your immune system protects you around the clock

While the above recommendations are not exhaustive, they do highlight many important considerations for a proactive approach to supporting your immune health. Nothing replaces good hygiene and staying home if you’re sick. However, your immune system is an amazingly complex coordination mechanism that protects you around the clock. You can make a difference and improve your immunity with these 8 specific lifestyle and nutritional measures.


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  2. Cohen S, Doyle WJ, Alper CM, Janicki-deverts D, Turner RB. Sleep habits and susceptibility to the common cold. Arch Intern Med. 2009;169(1):62-7.
  3. Nieman DC, Wentz LM. The compelling link between physical activity and the body’s defense system. J Sport Health Sci. 2019;8(3):201-217.
  4. Li Y, Innocentin S, Withers DR, et al. Exogenous stimuli maintain intraepithelial lymphocytes via aryl hydrocarbon receptor activation. 2011;147(3):629-40.
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  6. Ohio State University. Zinc helps against infection by tapping brakes in immune response. ScienceDaily, 7 February 2013.
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  9. Dabbagh-bazarbachi H, Clergeaud G, Quesada IM, Ortiz M, O’sullivan CK, Fernández-larrea JB. Zinc ionophore activity of quercetin and epigallocatechin-gallate: from Hepa 1-6 cells to a liposome model. J Agric Food Chem. 2014;62(32):8085-93.
  10. Lull C, Wichers HJ, Savelkoul HF. Antiinflammatory and immunomodulating properties of fungal metabolites. Mediators Inflamm. 2005;2005(2):63-80.
  11. Laukkanen JA, Laukkanen T, Kunutsor SK. Cardiovascular and Other Health Benefits of Sauna Bathing: A Review of the Evidence. Mayo Clin Proc. 2018;93(8):1111-1121.
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