The Wellness Primer, Part II

By Emeran Mayer, MD

Life is stressful, and for most people chronic stress has become a regular aspect of daily life. Stress has been part of human life for millions of years and there has been enough time in our evolutionary history to perfect our biological stress response systems in a way that has kept our species alive through natural disasters, wars, famines and pandemics. There are two such systems in our body: the older immune stress response system and the brain’s stress response system, and both are often engaged together.

Our organism responds to any situation – in the presence or the future – that is perceived as a threat to our integrity and homeostasis by engaging one or both of these stress response systems. While they have evolved and are optimized to respond to infrequent, but life threatening stresses – the poisonous snake, the wild tiger, the severe injury or the infection, for most people in developed countries, these are no longer the kind of stresses we encounter on a regular basis. (Unfortunately, the worry about being shot remains a persistent stress for a significant segment of the population as highlighted by the series of recent high profile police shootings). Rather, today’s stress most often comes in form of chronic stressors associated with modern life: the dietary stress on our metabolism in form of the unhealthy Standard American Diet (SAD), and the chronic psychological stress on our minds generated by the relentless daily bombardment with negative news, worries about the future, increasing competition, and challenges associated with a lower socioeconomic status (in plain language, poverty).

Unfortunately, these two type of stressors often occur together, and the relentless challenge of our stress systems comes at an increasing cost to the health of our bodies and minds. Evolution had not foreseen these kind of stresses which we have never experienced as a species. While the stress response systems keep responding in the same way that has been so adaptive for human life, chronic hyperproduction of the stress mediators cortisol and noradrenaline, and chronic systemic engagement of the immune system are responsible for many aspects of our current chronic non-infectious disease epidemic as I have described in detail in The Gut-Immune Connection.

Not everybody responds to these challenges in the same way: the responsiveness of our neurological and immunological stress system is programmed during the first 18 years of life, starting in utero, and will determine our lifetime risks for developing these common chronic diseases. This will result in a situation where two people exposed to the same kind and severity of stress will respond in very different ways: one will remain healthy, the other one developing a chronic disease.

In this short video clip, I provide a brief explanation of the relentless transition that has been occurring in the US and increasingly in developing countries from a state of optimal health and the associated subjective feeling of wellness to the current epidemic of chronic non-infectious diseases, and provide an understanding of how both psychosocial and dietary stresses interact to result in a maladaptive engagement of the stress systems ultimately leading to organ dysfunction and disease.

In the next edition of Gut Health Insights, I will talk about why women are more at risk to developing stress related diseases, and what stress hyperresponsive individuals can do to minimize the risk to develop such diseases. If you want to learn more about this topic, you might also be interested in my upcoming book The Gut-Immune Connection that you can order now.

Great news if you have already placed your pre-publication order for The Gut-Immune Connection, or if you intend to do so by April 26! A free signed copy of The Mind-Gut Connection is waiting for you!

Please send us a screenshot confirming your order to preorders@emeranmayer.com, and we will enter your name into a raffle to select 20 winners who will receive a signed copy of The Mind-Gut Connection. If you are chosen, you will be asked to send us your mailing address so we can ship you the signed copy.

But please remember, this offer will end on April 26!


Dr. Emeran Mayer is a Distinguished Research Professor in the Departments of Medicine, Physiology and Psychiatry at the David Geffen School of Medicine at UCLA and the Executive Director of the G. Oppenheimer Center for Neurobiology of Stress and Resilience at UCLA.


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