Immune Health

Last Updated: November 12, 2022

Immune health refers to the body's ability to resist potentially harmful microorganisms such as viruses and bacteria, and includes both innate and acquired immunity.

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What is immune health?

Immune health describes the immune system’s ability to heal and preserve bodily function when confronted by infection, injury (wound healing), and even malignancy. Our body relies on multiple levels of defense. These levels include physical barriers (skin and mucous membranes), inflammatory response inflammation, cellular response, and cellular adaptation.[1] Moderation and balance in these different levels of defense are key to optimal immune health. When the immune response is inadequate, this can open the door for infection by harmful pathogens. In contrast, an overzealous immune response could break tolerance of the immune system to ‘self’ molecules in the body, resulting in autoimmune disease. When it comes to immune health, balance is the key.[2]

How is immune health measured?

Healthy immune response includes the ability to accurately determine what is harmful to the body, adapt to changes in the environment, manage infections, and retain memory of what foreign cells cause damage.[2] One approach to quantifying immune health is by measuring biomarkers in blood that reflect each of these facets of the immune response. These biomarkers may include: leukocytes, lymphocytes, cytokines, T-cells, natural killer (NK) cells, monocytes, C-reactive protein, and antibodies. An important consideration here is that these biomarkers may be elevated as part of a healthy immune response, for example, to an infection. Concern may be warranted if there is an abnormally high level of inflammatory biomarkers or if they’ve been circulating at a higher than average level for an extended time.[3] [4]

Beyond blood tests, perceived immune status is a subjective assessment that may be more accessible to those outside of the clinical setting. The Immune Status Questionnaire (ISQ) was published in 2019, and is a validated self-assessment that may help individuals determine if they should seek medical attention, make lifestyle changes, or take further action to improve immune health.[5]

How does physical activity affect immune health?

Current research suggests that when it comes to exercise for immune health, moderation, balance, and consistency are key. Moderate exercise has been shown to have numerous benefits on immune health. Although physical activity is a stressor that does incite an immune response, the degree of the immune response and whether it’s harmful or helpful to immune health can be situationally dependent.

The current understanding is that consistent, moderate to vigorous intensity exercise (<60 minutes in length) is beneficial for immune health and can enhance adaptive immunity, thereby improving protection from community acquired illness and increasing the efficacy of vaccines.[6][7] Muscle contraction is also beneficial to immune health by releasing helpful immune mediators, aiding in lymphatic drainage of waste products, and possibly even diversifying the gut microbiome.[1][8] On the other hand, extreme exercise (especially in the untrained) can be detrimental to immune health. When healing from extreme exercise, the immune system becomes preoccupied and can devote fewer resources to defense.[9]

Have any supplements been studied for immune health?

The effects of many supplements on immune health markers have been studied, and the research is ongoing. As of 2022, some of the most frequently studied supplements for immune health include Fish Oil, Vitamin C, Colostrum, Spirulina, Astaxanthin, Reishi, Vitamin D, Vitamin E, Boron, Conjugated Linoleic Acid, and Garlic. Many of these supplements have been studied for their ability to improve immunity by limiting inflammation or by enhancing the body’s defense against damaging compounds, such as free radicals. Two exceptions to this list are Vitamin D and Garlic, both of which are primarily known for their ability to help the body manage or resist infections. A group of supplements that individually have been studied to a lesser degree on this topic, but that collectively present a noteworthy body of evidence, are adaptogens. Adaptogenic plants (such as Eleuthero, Ginseng, Ashwagandha, Rhodiola rosea, and Astragalus) are thought to work primarily through their ability to help the body adapt to stress.[10]

How can diet affect immune health?

Diet can impact most physical functioning, so it’s no surprise that it can also play a role in immune health. Similar to the ways supplements have been studied, the focus has been on the ability of nutrients to either reduce susceptibility to infection or to enhance healing through modulating inflammation and oxidation. Current research suggests that when part of the diet, plant-based compounds such as flavonoids may reduce incidence, duration, and severity of upper respiratory infection.[11] Foods like blueberries and grapes tend to be high in flavonoids (anthocyanidins and flavonols), which have antioxidant properties that may enhance immune health. Beyond flavonoids and their antioxidant capacity, complete plant-based diets, such as the Autoimmune Protocol and vegan diets, are full of phytochemicals, fiber, vitamins, and minerals, all of which can contribute to immune health.[12] Alterations in the gut microbiome may also play a role in immune health,[13] which could explain why diets that include probiotic-rich foods, such as Kefir, have potential immune-enhancing effects

What other factors affect immune health?

Stress exposure, sleep, and metabolic health all have both distinct and overlapping effects on immune health. Sleep has a profound effect on the immune system, and consistently getting enough of it can improve the ability to fight off infections (or avoid them altogether) and increase the efficacy of vaccines.[14] Excessive stress (either psychological or physiological) can have positive or negative effects on immune health, depending on the type of exposure. For example, temporary stress from exercise or public speaking can have positive effects on immune health,[15] while chronic stress exposure can impair immune health by limiting the ability of the immune system to fight off infections and/or increasing the risk of autoimmune disease.[16] Metabolic health — in particular the ability of the body to regulate blood sugar levels — also plays a significant role in immune health, since impaired blood sugar control and insulin resistance have widespread negative effects on the immune system.[17]

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  1. ^Braun C, Anderson CApplied Pathophysiology: A conceptual approach to the mechanisms of disease, 3rd Edition(2017)
  2. ^Nicholson LBThe immune system.Essays Biochem.(2016-10-31)
  3. ^Claus M, Dychus N, Ebel M, Damaschke J, Maydych V, Wolf OT, Kleinsorge T, Watzl CMeasuring the immune system: a comprehensive approach for the analysis of immune functions in humans.Arch Toxicol.(2016-Oct)
  4. ^Institute of Medicine (US) Committee on Military Nutrition ResearchMilitary Strategies for Sustainment of Nutrition and Immune Function in the Field: Overview of Immune Assessment Tests(1999)
  5. ^J F Wilod Versprille L, J A E van de Loo A, Mackus M, Arnoldy L, A L Sulzer T, Vermeulen SA, Abdulahad S, Huls H, Baars T, Scholey A, Kraneveld AD, Garssen J, Verster JCDevelopment and Validation of the Immune Status Questionnaire (ISQ).Int J Environ Res Public Health.(2019-11-27)
  6. ^Brown WM, Davison GW, McClean CM, Murphy MHA Systematic Review of the Acute Effects of Exercise on Immune and Inflammatory Indices in Untrained Adults.Sports Med Open.(2015)
  7. ^Sebastien F M Chastin, Ukachukwu Abaraogu, Jan G Bourgois, Philippa M Dall, Jennifer Darnborough, Elaine Duncan, Jasmien Dumortier, David Jiménez Pavón, Joanna McParland, Nicola J Roberts, Mark HamerEffects of Regular Physical Activity on the Immune System, Vaccination and Risk of Community-Acquired Infectious Disease in the General Population: Systematic Review and Meta-AnalysisSports Med.(2021 Apr 20)
  8. ^Clark A, Mach NExercise-induced stress behavior, gut-microbiota-brain axis and diet: a systematic review for athletes.J Int Soc Sports Nutr.(2016)
  9. ^Nieman DC, Wentz LMThe compelling link between physical activity and the body's defense systemJ Sport Health Sci.(2019 May)
  10. ^Todorova V, Ivanov K, Delattre C, Nalbantova V, Karcheva-Bahchevanska D, Ivanova SPlant Adaptogens-History and Future Perspectives.Nutrients.(2021-Aug-20)
  11. ^Vaughan S Somerville, Andrea J Braakhuis, Will G HopkinsEffect of Flavonoids on Upper Respiratory Tract Infections and Immune Function: A Systematic Review and Meta-AnalysisAdv Nutr.(2016 May 16)
  12. ^Krasimira Aleksandrova, Liselot Koelman, Caue Egea RodriguesDietary patterns and biomarkers of oxidative stress and inflammation: A systematic review of observational and intervention studiesRedox Biol.(2021 Jun)
  13. ^Badal VD, Vaccariello ED, Murray ER, Yu KE, Knight R, Jeste DV, Nguyen TTThe Gut Microbiome, Aging, and Longevity: A Systematic Review.Nutrients.(2020-Dec-07)
  14. ^Besedovsky L, Lange T, Haack MThe Sleep-Immune Crosstalk in Health and DiseasePhysiol Rev.(2019 Jul 1)
  15. ^Segerstrom SC, Miller GEPsychological stress and the human immune system: a meta-analytic study of 30 years of inquiry.Psychol Bull.(2004-Jul)
  16. ^Dhabhar FSEffects of stress on immune function: the good, the bad, and the beautifulImmunol Res.(2014 May)
  17. ^Berbudi A, Rahmadika N, Tjahjadi AI, Ruslami RType 2 Diabetes and its Impact on the Immune System.Curr Diabetes Rev.(2020)
  18. ^Noushad S, Ahmed S, Ansari B, Mustafa UH, Saleem Y, Hazrat HPhysiological biomarkers of chronic stress: A systematic review.Int J Health Sci (Qassim).(2021)
  19. ^Lee A, Kinney P, Chillrud S, Jack DA Systematic Review of Innate Immunomodulatory Effects of Household Air Pollution Secondary to the Burning of Biomass Fuels.Ann Glob Health.(2015)
  20. ^Prather AA, Janicki-Deverts D, Hall MH, Cohen SBehaviorally Assessed Sleep and Susceptibility to the Common ColdSleep.(2015 Sep 1)
  21. ^Black DS, Slavich GMMindfulness meditation and the immune system: a systematic review of randomized controlled trials.Ann N Y Acad Sci.(2016-06)
  22. ^Andersen L, Corazon SSS, Stigsdotter UKKNature Exposure and Its Effects on Immune System Functioning: A Systematic Review.Int J Environ Res Public Health.(2021-02-03)
  23. ^Stier-Jarmer M, Throner V, Kirschneck M, Immich G, Frisch D, Schuh AThe Psychological and Physical Effects of Forests on Human Health: A Systematic Review of Systematic Reviews and Meta-Analyses.Int J Environ Res Public Health.(2021-02-11)
  24. ^Kornberg MDThe immunologic Warburg effect: Evidence and therapeutic opportunities in autoimmunity.Wiley Interdiscip Rev Syst Biol Med.(2020-09)
  25. ^Nojima I, Eikawa S, Tomonobu N, Hada Y, Kajitani N, Teshigawara S, Miyamoto S, Tone A, Uchida HA, Nakatsuka A, Eguchi J, Shikata K, Udono H, Wada JDysfunction of CD8 + PD-1 + T cells in type 2 diabetes caused by the impairment of metabolism-immune axis.Sci Rep.(2020-09-10)
  26. ^Spindler MP, Ho AM, Tridgell D, McCulloch-Olson M, Gersuk V, Ni C, Greenbaum C, Sanda SAcute hyperglycemia impairs IL-6 expression in humans.Immun Inflamm Dis.(2016-Mar)
  27. ^Price CL, Hassi HO, English NR, Blakemore AI, Stagg AJ, Knight SCMethylglyoxal modulates immune responses: relevance to diabetes.J Cell Mol Med.(2010-Jun)
  28. ^Singh VP, Bali A, Singh N, Jaggi ASAdvanced glycation end products and diabetic complications.Korean J Physiol Pharmacol.(2014-Feb)
  29. ^Clement CC, Nanaware PP, Yamazaki T, Negroni MP, Ramesh K, Morozova K, Thangaswamy S, Graves A, Kim HJ, Li TW, Vigano' M, Soni RK, Gadina M, Tse HY, Galluzzi L, Roche PA, Denzin LK, Stern LJ, Santambrogio LPleiotropic consequences of metabolic stress for the major histocompatibility complex class II molecule antigen processing and presentation machinery.Immunity.(2021-04-13)
  30. ^Poznyak A, Grechko AV, Poggio P, Myasoedova VA, Alfieri V, Orekhov ANThe Diabetes Mellitus-Atherosclerosis Connection: The Role of Lipid and Glucose Metabolism and Chronic Inflammation.Int J Mol Sci.(2020-Mar-06)