Dysbiosis IIIITrillions of microorganisms colonize our gastro-intestinal tract and make an important contribution to our health. High-throughput sequencing techniques and new bioinformatic tools have enabled scientists to discover interactions between our genes, our gut microbiota, and our emotions.

Our genetics and our diet weigh heavily in determining the composition of our gut microbiome. Take for example a genetic variant responsible for sucrose intolerance. The mutation reduces the efficiency of an enzyme that is key to digesting starch and sugars. In turn, this leads to unabsorbed carbohydrates and a deleterious shift in gut microbiota composition.

In the absence of mutations that impair digestive enzyme function, however, plant-based diets promote the enrichment of beneficial microflora and competent immune responses. Nutrient-poor diets, combined with long-term exposure to psychological stress, induce imbalances in the microbiome known as dysbiosis. Dysbiosis is strongly associated with neuroinflammation and impaired stress responses.


Risk On OffGut microbes produce neurotransmitters that are identical to those produced by humans and that enter the brain, where they influence reward systems, impulsivity, emotions, and cognition. (1)

The gut-brain axis is a two way street. Chronically elevated stress hormones such as cortisol reduce the diversity of gut microorganisms, increase gut permeability, and activate immune-induced low-grade systemic inflammation.


Yes. Risk taking is central to decision making and to investing. There is abundant evidence that variation in genes regulating one’s stress response undermine investment decision making. And because loss aversion counterproductively diminishes an investor’s expected returns, it has become one of the most studied decision biases. In an individual, genetically susceptible to poor emotion regulation, gut dysbiosis promotes neuroinflammation, negative emotional states, and poor decision making. Thus, it is the combined effects of one’s genetic variation, gut health, environmental choices and long-term adaptive responses to portfolio stressors that alter the investor’s willingness to take risks for reward. 

  1. Galland L. The gut microbiome and the brain. J Med Food. 2014 Dec;17(12):1261-72.