According to the American Psychological Association (APA), stress may be defined as any uncomfortable “emotional experience accompanied by predictable biochemical, physiological and behavioral changes.” Stress can produce and contribute to negative health and quality-of-life outcomes. Prolonged or chronic stress can be particularly detrimental and has been linked to serious illness and disease.
The Mayo Clinic has identified chronic stress as a health risk because of the dangers linked to prolonged exposure to the hormones that are released during the stress response and the potential health threats this unnatural exposure can present. These may include
- Sleep problems
- Weakened immunity
- Heart disease
- Digestive problems
- Impaired memory and concentration.
So what happens to our bodies when we’re under stress? And how does that amplify when we’re under persistent or chronic stress?
What is the Fight or Flight Response?
According to Harvard Medical School, the fight or flight response is an almost immediate response in the body to perceived threats. It allows us to access reserves of energy in order to run away to safety—flight—or stand our ground and defend ourselves—fight—a function of survival involving the autonomic nervous system, specifically the sympathetic nervous system.
The sympathetic nervous system brings our bodies into temporary high alert status for emergency situations. The pathways involved in this stress response precede logical conscious “thought,” and initiate even before the brain’s visual centers have had time to fully process the event that has triggered it. So, even before the brain has had time to figure out what’s actually happening, the stress response is already in progress.
How Does the Stress Response Work?
The fight or flight response begins with a stimulus, usually perceived through the eyes and/or ears. This signal moves straight to the amygdala, an emotional processing center. When the amygdala identifies the stimulus as a potential threat, it sends a signal of distress directly to the hypothalamus, the body’s command center.
When this command center is activated, it precedes what we normally think of as “conscious thought.” Changes within the body occur without our conscious and deliberate input. Because these reactions take place so rapidly and bypass regular mental way stations, they affect us before we have had time for mental processing of events to take place.
In true life-or-death situations, this bypassing of logical thought has a distinct advantage. For example, the fight or flight response is quite useful if we’re being chased by a grizzly bear or lion. However, events that are not, in retrospect, life-threatening can also trigger the same response. What we have is an automatic response that can be viewed as both a blessing and a curse.
In the hypothalamus, the distress signal is sent through our autonomic nerves to the adrenal glands. These glands are called the adrenals because they produce a substance called adrenaline, also known as the hormone epinephrine. You have likely heard adrenaline linked with numerous negative health outcomes, such as high blood pressure. Epinephrine does, in fact, create the following physiological changes in the body during the stress response:
- Faster heartbeat
- Pushes blood to muscles
- Sends extra blood to heart and other vital organs
- Faster pulse rate
- Rise in blood pressure
- Increase in breath rate
- Small airways in lungs open
- Lungs absorb as much oxygen as possible
- Extra oxygen to brain
- Increased alertness
- Sight and hearing sharpen
- Release of blood sugar (glucose)
- Release of fats
Basically, the stress response makes all available resources accessible to the entire body for instant energy to run to safety or to stand and fight for our lives if necessary.
The HPA Axis
After the adrenals release epinephrine and all parts of the body have been given access to all potential sources of energy, the second aspect of the stress response system activates. This next step in the response involves what is known as the HPA axis.
HPA is an acronym for hypothalamus, pituitary, and adrenals. The HPA axis is responsible for keeping the stress response going. It acts to sustain the stress response in the body through sets of hormonal signals.
First, the hypothalamus sends corticotropin-releasing hormone (CRH) to the pituitary gland. The pituitary gland is then triggered to release adrenocorticotropic hormone (ACTH), which travels to the adrenals. This signal, in turn, triggers the release of cortisol. Through the release of these hormones, the body stays on high alert status.
When the potential threat is removed, these elevated hormonal levels return to normal status, and the stress response is released. The sympathetic nervous system is then disengaged, and the body returns to homeostasis, a state of balance—that is, under “normal” circumstances.
However, with chronic stress, potential perceived threats are more frequent and can sometimes cause the body to stay on high alert for prolonged periods, thus causing the body to sustain unusually high levels of these hormones for too long—so often and so long that there are serious and lasting health implications.
Within the autonomic nervous system, we have both the sympathetic and parasympathetic nervous systems guiding the body’s physiological responses. The sympathetic, again, puts us on alert for potential dangers and gives us the “juice” to fight or flee.
In the converse, the parasympathetic nervous system tells us it’s okay to relax. It is activated when we feel safe, when we are in a safe location, when we perceive no potentially dangerous threats around us.
When the parasympathetic nervous system is activated, we feel calm. Our bodies reflect this through
- Lower blood pressure
- Lower heart rate
- Slower pulse
- Even breathing
- Lower cortisol levels
- Lower adrenaline (epinephrine).
Our bodies are allowed then to “rest and digest” rather than being on our guard—two things the stress response prevents our bodies from doing properly.
The Symptoms of Chronic Stress
Chronic stress can cause us to experience a wide range of behavioral, physical, and emotional conditions. According to the American Institute of Stress, some of the physical symptoms of chronic stress can include, but are not limited to,
- Muscle aches and spasms
- Excessive sweating
- Dry mouth
- Rashes and hives
- Chest pain or palpitations
- Weight gain or loss
- Weakness and fatigue
Moreover, because of the persistent surges in epinephrine, our blood vessels and arteries can suffer damage, and the elevated blood pressure rates increase the risk of heart attack and stroke.
Elevated cortisol levels can increase the appetite and lead to unwanted weight gain. Another of the possible negative health outcomes associated with chronic stress is type 2 diabetes. Cortisol and other stress hormones are able to bypass insulin responses. Therefore, when in the stress response, the cells in the body can become effectively insulin-resistant, and blood sugar levels can remain too high.
In addition, chronic stress can induce or contribute to several behavioral changes which may include dysfunctional behaviors that cause our quality of life to decrease even more. We can be affected by these symptoms that can decrease our quality of living—our lifestyle, our finances, our relationships. These can include
- Reduced work efficiency
- Impaired concentration
- Problems in communicating
- Difficulty in making decisions
- Diminished sexual desire
- Excessive gambling or impulse buying.
Those under chronic stress can also exhibit the following emotional symptoms that can disrupt our peace of mind:
- Sudden bouts of panic
- Frequent crying spells
- Feelings of worthlessness
- Loneliness and isolation
- Anxiety, worry, guiltT
Warning Signs of Chronic Stress
According to the APA, chronic stress can lead to a multitude of signs and symptoms. If you or someone you know is showing these signs, you may be experiencing the effects of chronic stress. Warning signs may include
- Headaches, neck or back pain
- Upset stomach
- Difficulty falling or staying asleep
- Appetite changes
- Increased frequency of colds
- Lack of focus
- Chest pain or rapid heartbeat
- Irritability or short temper
Is Chronic Stress Linked to Depression?
Yes, chronic stress is strongly linked to depression, as well as anxiety. When we are exposed to chronic stress, we are much more likely to show signs of depression. As a matter of fact, the two can perpetuate one another. Chronic stress can contribute to depression, and experiencing depression and trying to cope with its debilitating symptoms and real-world negative outcomes can create additional stressors for us. And thus the cycle continues and may continue in a downward spiral for us.
Those who experience chronic stress are far more likely to have serious symptoms of depression, such as feelings of worthlessness, social withdrawal, and even thoughts of suicide.
Chronic stress, depression, and anxiety are also associated with increased risks for substance abuse, including alcohol and dependency on over-the-counter drugs.
Because of the highly negative physiological, psychological, and emotional effects of chronic stress, including its links to heart disease, diabetes, and obesity, it is important that we educate ourselves and others about its potential dangers.
The hormones involved in the body’s stress responses are associated with anxiety, depression, and addictive behaviors such as substance abuse and gambling. It is crucial that we recognize the role that chronic stress can play in our lives and the negative and unwanted outcomes it can generate in our everyday lives.
Understanding chronic stress is far more involved than merely learning about adrenaline and rapid breathing. It is about identifying the presence of chronic stress in our lives, recognizing its potential implications within our bodies, our social lives, and our families. It’s about educating ourselves regarding the effects it can have on our jobs, our mental and physical state, and our own peace of mind.
Through a deepened understanding and awareness of chronic stress and its potentially negative effects on our well-being, we can continue to move forward on our journey toward living our best life possible.