Chronic Stress, Cortisol Resistance & Immunity

Decades of research has highlighted the impact of stress on the immune system. Whilst acute stress has been shown to enhance the immune response, chronic stress has been shown to suppress immune function and is a major player in immune depletion and treatment resistance.[7-9]

Chronic stress takes place over an extended period of time and can elicit declines in Th1 (IL-2, IFN-gamma and IL-12) and Th2 (IL-4) responses, i.e. immunosuppression. People reporting more psychological stress have both a higher incidence and a greater severity of illness.[10]

An important finding is that exposure to chronic stress results in glucocorticoid receptor (GCR) resistance leading to a failure to down-regulate the inflammatory response. Consequently, higher levels of IL-6 are produced with an exaggerated expression of the signs and symptoms of infection.[10]

In this infographic, we take a closer look at the effects of chronic stress and how it interferes with the regulation of local pro-inflammatory cytokine response to common infections. We also review some of the key herbal immunomodulators and adaptogens that have been shown to improve the stress and inflammation response and reduce our susceptibility to infection.

References

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8. Lucassen PJ, Pruessner J, Sousa N, et al. Neuropathology of stress. Acta Neuropathol 2014;127:109-135. [Full text]
    
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10. Cohen S, Doyle W, Skoner D. Psychological stress, cytokine production, and severity of upper respiratory illness. Psychosomatic Med 1999;61:175-180. [Abstract]
     
11. Reflection paper on the adaptogenic concept. Committee of Herbal Medicinal Products (HMPC). European Medicines Agency: London, 2008. [Full text]
     
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13. Singh N, Bhalla M, de Jager P, et al. An overview on Ashwagandha: A Rasayana (Rejuvenator) of Ayurveda. Afr J Tradit Complement Altern Med 2011;8(S):208-213. [Full text]
     
14. KSM-66 Ashwagandha analytical specifications. Viewed 28 Aug 2014, www.ksm66ashwagandhaa.com/specification_sheet.html