Gut Health and the Immune Response

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Gut dysbiosis enhances the aggressiveness of viral lung disease. This is well known for the influenza virus and could be the same for coronavirus.

– Francesco Di Pierro, PhD

Much of the body’s immune response depends on the microbiome, and understanding its complexities and potential therapeutic targets is even more important during the COVID-19 pandemic. At IFM’s 2020 Annual International Conference (AIC) online experience, expert researchers and clinicians will outline advances and new perspectives regarding the microbiome and its essential role in supporting health during the pandemic and beyond. From pediatric to ecological considerations, the microbiome will be a primary topic in several AIC presentations that address the restoration, strength, and resilience of health in individuals and populations:

See the AIC 2020 schedule for a complete list of presentations and speakers.

Immune System Integrity and the Gut Microbiome

Microbial communities essential for growth, health, and survival exist across the planet, from soil microbiomes to the commensal microbiota in our guts. Studies show that the maintenance of a healthy gut microbiome is in fact inseparable from host health.1 Supporting a balanced intestinal microbial community is essential for the integrity of the immune system, for the prevention and response to infections, and for recovery from illness.

The immune system, which is primarily in the gut, is influenced and actually taught by the gut microbiome.

– Dr. Hanaway

The microbes and their metabolites influence physiological function (particularly metabolism), local mucosal homeostasis, inflammation, and interactions between multiple body systems.1-4 Therefore, an imbalanced intestinal microbiota may have system-wide effects and contribute to blunted immune reactivity.5

Nutrition: Common Foods for Healthy Immunity and a Healthy Gut

Gut microbiota alterations due to unhealthy lifestyle factors and dietary triggers may contribute to inflammation, intestinal permeability, immune system dysfunction, and the pathogenesis of a broad spectrum of chronic diseases. Healthy lifestyle factors, including a diversified diet, limited consumption of processed and refined foods, and consumption of adequate dietary fiber, may all promote a healthy microbiome.1

Foods and nutrients that potentially boost immune function also tend to promote gut health. For example, consuming a diverse array of fruits and vegetables rich in antioxidants, anti-inflammatory nutrients, and phytochemicals may reduce oxidative stress, support the liver to promote efficient biotransformation and detoxification, and boost overall immune system function.6-10 These same fruits and vegetables also contain soluble fibers that “feed” the commensal microbial community in the colon to optimize gut balance and health and insoluble fibers that assist in the efficient processing and elimination of waste from the intestinal tract.

Clinical Applications

Supporting a healthy microbiome is a cornerstone of Functional Medicine and essential for strengthening immune responses and improving overall health. Personalized therapeutic interventions that focus on modifiable lifestyle factors may optimize immune system function while supporting gut health. Such lifestyle modifications may include the following:

  • Therapeutic food plans
  • Multi-strain probiotic supplementation
  • Adequate sleep and sleep quality
  • Movement and exercise plans
  • Reduction of dietary triggers and toxic exposures
  • Stress management or transformation

The microbiome helps determine the vitality of the immune system, as well as its 'set-point' for the pro-inflammatory response to infection.”

– Dr. Hanaway

As the timeframe of the current pandemic continues to expand, implementing personalized treatment approaches that support the health and balance of the intestinal microbiome may be essential to not only strengthen resilience for high-risk chronic disease patients, but also to optimize immune function and disease prevention for healthy patients. Learn more about the latest microbiome research and clinical applications at this year’s AIC.

AIC 2020 recordings are available for purchase here


  1. Shanahan F, van Sinderen D, O’Toole PW, Stanton C. Feeding the microbiota: transducer of nutrient signals for the host. Gut. 2017;66(9):1709-1717. doi:1136/gutjnl-2017-313872
  2. Cammarota G, Ianiro G. Gut microbiota and cancer patients: a broad-ranging relationship. Mayo Clin Proc. 2017;92(11):1605-1607. doi:1016/j.mayocp.2017.09.009
  3. Lach G, Schellekens H, Dinan TG, Cryan JF. Anxiety, depression, and the microbiome: a role for gut peptides. Neurotherapeutics. 2018;15(1):36-59. doi:10.1007/s13311-017-0585-0
  4. Cryan JF, O’Riordan KJ, Cowan CSM, et al. The microbiota-gut-brain axis. Physiol Rev. 2019;99(4):1877?2013. doi:10.1152/physrev.00018.2018
  5. Brzozowski B, Mazur-Bialy A, Pajdo R, et al. Mechanisms by which stress affects the experimental and clinical inflammatory bowel disease (IBD): role of brain-gut axis. Curr Neuropharmacol. 2016;14(8):892-900. doi:10.2174/1570159×14666160404124127
  6. Hodges RE, Minich DM. Modulation of metabolic detoxification pathways using foods and food-derived components: a scientific review with clinical application. J Nutr Metab. 2015;2015:760689. doi:10.1155/2015/760689
  7. Jackson SJ, Singletary KW, Murphy LL, Venema RC, Young AJ. Phytonutrients differentially stimulate NAD(P)H:quinone oxidoreductase, inhibit proliferation, and trigger mitotic catastrophe in hepa1c1c7 cells. J Med Food. 2016;19(1):47-53. doi:10.1089/jmf.2015.0079
  8. Abbaoui B, Lucas CR, Riedl KM, Clinton SK, Mortazavi A. Cruciferous vegetables, isothiocyanates and bladder cancer prevention. Mol Nutr Food Res. 2018;62(18):e1800079. doi:10.1002/mnfr.201800079
  9. Jiang X, Liu Y, Ma L, et al. Chemopreventive activity of sulforaphane. Drug Des Devel Ther. 2018;12:2905-2913. doi:10.2147/DDDT.S100534
  10. Minich DM, Brown BI. A review of dietary (phyto)nutrients for glutathione support. Nutrients. 2019;11(9):2073. doi: 10.3390/nu11092073

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