Is Stress Affecting Your Microbiome?

Stress increases cortisol, which may have a profound impact on the gastrointestinal (GI) microbiota and metabolome, selectively decreasing beneficial bacteria and secretory IgA (sIgA). Thus, it is not surprising that clinical interventions implemented to resolve GI symptoms may not be completely successful if stress is not considered as a potential root cause.

Chronic stress directly effects our gastrointestinal health via hypothalamic-pituitary-adrenal (HPA) axis activation. Stress can adversely affect GI bacteria and secretory IgA (sIgA), which may influence intestinal permeability, and selectively decrease beneficial bacterial species.

CHRONIC STRESS WILL DOWN REGULATE FAECAL sIgA, WHICH INCREASES THE RISK OF GI INFECTION

Animal models have provided insight into stress and its effects on the GI microbiome. Stress caused by maternal separation of rhesus monkeys changed their microbiome via decreased Bifidobacterium and Lactobacillus. Rat pups separated from their mother exhibited decreased Lactobacillus levels which was maintained for an extended period of time. As such, acute and chronic stress may lead to the development of intestinal dysbiosis and chronic low grade inflammation. Gastrointestinal dysbiosis and chronic low-grade inflammation have been implicated in IBS and depression.

Chronic stress weakens the intestinal mucosal barrier and permits paracellular bacterial translocation from the lumen. This stimulates the activation of the inflammatory meditators, resulting in activation of the HPA axis.

OUR MODERN LIFESTYLES OFTEN LEAD TO THE DEVELOPMENT OF CHRONIC STRESS AND FURTHER SYSTEMIC SYMPTONS IN THE FORM OF INCREASED HPA AXIS ACTIVATION, INCREASED FAECAL SIGA, DISTURBANCES IN THE GI MICROBIAL COMPOSITION AND INCREASED INTESTINAL PERMEABILITY.

We can evaluate levels of faecal sIgA, the GI microbiota, and intestinal permeability to gain insight into potentially confounding roles of stress on GI and systemic symptoms. Testing HPA axis function and neurotransmitter secretion can be an important tool in helping to address the imbalances that can result from long-term chronic stress. Stress management should is always considered to be part of a comprehensive clinical intervention.