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How Chronic Stress Affects Physiology and Well-Being

Sustained exposure to stress hormones causes inflammation and tissue damage.

Key points

  • Sustained exposure to real or perceived threat keeps the body in fight or flight mode, wearing down defenses over time.
  • The essence of disease is sustained threat and prevention starts with connecting to a sense of safety using specific strategies.
  • Shifting the body’s function from fight and flight to rest and digest is accomplished through learning how to create feelings of safety.
Image by Peggy und Marco Lachmann-Anke from Pixabay
Source: Image by Peggy und Marco Lachmann-Anke from Pixabay

All living creatures survive by mobilizing resources in their bodies to deal with threats and replenishing them when feeling safe. Both are necessary for life. However, sustained exposure to threats causes a shift in the chemical profile that breaks down your body, causing mental and physical diseases. (1)

It is important to understand the nature of threats, the various ways they present, and the makeup of your body’s neurochemistry in a survival flight or fight mode. In other words, your body is collecting a massive amount of data from multiple sensors in your body that is transmitted to the nervous system, which is translating it into action. The reaction causes changes in your physiology, stimulates physical actions, and creates behaviors that are appropriate to the situation.


Physiology is the term that describes how the body functions. We stay alive because living creatures maintain an incredibly delicate balance of the body’s acid/ base balance, electrolytes, blood pressure, temperature, heart rate, and the list is long. It is a dynamic process that changes by the second in response to input from your surroundings.

The physiological changes cause sensations that we call emotions. But emotions are just words that describe what you feel when your body is in action. Your physiological state affects every organ system and translates into symptoms. Every physical and mental symptom you experience is explained by an inherited problem, an identifiable structural abnormality, or changes in your body’s physiology—there no such entity as unexplained symptoms.

The Nature of Threats

Any mental or physical threat, perceived or real, is going to be met with a defensive response from your body. Much of this mediated through the autonomic nervous system (ANS). It is called “autonomic” because all the effects are automatic in response to input. The stimulation/ survival aspect is a function of the sympathetic nervous system (SNS), and the calming part is mediated through the parasympathetic nervous system (PNS). The vagus nerve is the main nerve that transmits these signals. It is the 10th cranial nerve that originates in the midbrain just below the brain.

Physical threats include allergens, parasites, bacteria, viruses, lions, tigers, bears, and people we perceive as or are dangerous. Less obvious but even more inflammatory are mental threats because we can’t physically escape our thoughts and emotions. Repressed ones are even more problematic.

Mental threats are processed similarly in the brain as physical ones and cause an inflammatory response that forms the basis for chronic mental and physical disease when sustained. Examples of mental threats are memories, negative thoughts, suppressions, repressions, insecurities (social, financial, health, etc.), cognitive distortions, and loss of life perspective and purpose.

The Body’s Chemical Makeup Under Threat

The survival response is the well-known flight, fight, freeze, and faint reaction. (2) We are all familiar with the physical manifestations of threat, including an increased heart rate, sweating, muscle tension, and elevated blood pressure. But what you may not know is that the immune system also gets fired up and mobilizes many types of cells that fend off predators such as bacteria, viruses, and cancer cells. Cytokines are the signaling mechanism to mobilize or calm this response.

Cytokines are small proteins that serve as messengers throughout the body, transmitting higher-level signals and coordinating activities at the cellular level. They are central to modulating the immune system and inflammatory response. There are two kinds of cytokines: pro-inflammatory (Pro-I) and anti-inflammatory (Anti-I). While Pro-I cytokines protect us by warding off acute perils, Anti-I cytokines keep us safe by allowing us to regenerate, thrive, and prepare us for battle with environmental/ internal enemies.

When threats activate pro-inflammatory (Pro-I) cytokines, the resulting inflammation allows “warrior cells” to exit the bloodstream through widened openings in the vessels to destroy the invaders (antigens). However, when they are chronically activated, inflammatory cells will destroy normal tissues. They are elevated in almost every chronic disease state. For example, researchers discovered that some types of depression are inflammatory responses of the central nervous system to chronic stress. (3) Anxiety, bipolar, obsessive-compulsive disorder (OCD), and schizophrenia also have elevated inflammatory markers. (4) Chronic stress also causes early mortality. (5)

The Body’s Chemical Profile When Feeling Safe

Anti-inflammatory (Anti-I) safety cytokines are the underpinnings of health and wellness. With the elevations of the Anti-I’s, we see the states of “breed and feed” and “digest and rest.” We are restorative, connected, bonded, sexual, reproductive, cognitive, and creative. We also have high immunity.

There is a dramatic difference in your body’s neurochemical makeup when you feel safe compared to sensing danger. There is a deep sense of relaxation, contentment, sense of well-being. So, why do we not exist in this state most of the time? Generating a sense of safety is complicated for humans in that we have language and consciousness that is not present in any other species of life. You cannot outrun your mind.

Source: svitlanasagan/AdobeStock

The Essence of Healing

The essence of disease is sustained threat, and the solution lies in connecting to your sense of safety using specific strategies.

Discovery and acknowledgment of all our threats--whether real, imagined, anticipated, or repressed--is the first step towards addressing them. The second is choosing an adaptive rather than maladaptive escapes to safety, whether the threat is physical or spiritual. We are better at physical escapes to safety than we are at spiritual ones.

If you have a choice of solving an unpleasant situation, that is clearly the first choice. But the stresses that have the greatest impact on your health are the ones that are not solvable. Being trapped by anything or anyone really fires up your defenses. But since you can’t escape your consciousness, what can you do?

Dealing with Threat While Creating Safety

Creating safety is a learned skill, and each person will have a specific sequence based on their tolerance. The anger from being trapped by pain is intense and unpleasant but also powerful and protective. The antithesis of anger is vulnerability, which living creatures are not naturally programmed to allow. You must build a foundation and learn safety at a doable level. Then it is important to proceed at your own pace to tolerate being vulnerable and still feel safe. If you dive in too quickly without a solid base, you will react in a way that makes your defenses stronger. As you deliberately progress through the healing journey, you will learn to trust your skills and discover ways to find safety regardless of the circumstances. You have regained control of your life.


The essence of chronic disease is sustained exposure to threats. The solution lies in learning ways to find safety. Although you cannot control your thoughts and most of your external stresses, you control shifting your body’s physiology. They are simple tools that become automatic with repetition. Acquiring these skills will allow you to live your life on your own terms – and feel safe.

The next issue is the need to tolerate vulnerability. There are no rewards in nature for being vulnerable. You won’t survive, and that includes humans. Yet being vulnerable is the core of human relationships. But what if you were abused and don’t inherently trust people – and why would you?

We Have a Dilemma

  • The essence of chronic disease is sustained exposure to threat (feeling vulnerable).
  • Yet allowing yourself to be vulnerable is at the core of human relationships.
    • You must be able to trust someone before that can happen.
    • If you had a chaotic, even abusive upbringing, how do you know who to trust?
  • What happens if you don’t have the tools to deal with rejection or being hurt?
    • How can you feel safe while allowing vulnerability?
    • Every relationship requires taking risks.
  • You must be able to trust someone before that can happen.
  • If you had a chaotic, even abusive upbringing, how do you know who to trust?
  • How can you feel safe while allowing vulnerability?
  • Every relationship requires taking risks.

This is one of the main reasons you must learn how to feel safe in a sequence and at a comfortable pace. It is not a straight-line path, nor will it ever be. You do have to care for yourself and learn to “fail.” Every person has their own way of learning to feel safe and live life on his or her own terms.


1. Smyth J, et al. Stress and disease: A structural and functional analysis. Social and Personality Psychology Compass (2013);7/4:217-227. 10.1111/spc3.12020

2. Porges Stephen. The Pocket Guide to the Polyvagal Theory: The Transformative Power of Feeling Safe. Norton and Co, New York, NY, 2017.

3. deHeer, EW, et al. The association of depression and anxiety with pain: A study from NESDA. PLOSone (2014); 9:1-11. e106907.

4. Shields SS, et al. Psychosocial interventions and immune system function. JAMA Psychiatry(2020); doi:10.1001/jamapsychiatry.2020.0431

5. Torrance N, et al. Severe chronic pain is associated with increased 10-year mortality: a cohort record linkage study. Eur J Pain (2010);14:380-386.

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