Stress is harmful, it degrades our health, damages our hearts, and shortens life. There is no doubt that stress and health are linked. In 1967, two psychiatrists, Thomas Holmes and Richard Rahe, conducted a study of 5000 patient’s medical records to determine the extent that stress and health problems are a cause and effect. There was a positive correlation.
The Holmes and Rahe Studies About Stress and Health
The study resulted in the Holmes and Rahe stress scale that listed 43 life events and their corresponding “life change units (LCU)”. Death of a spouse was at the top of the list and had an LCU of 100. A total of 300+ LCUs in ones life indicates the a high risk of illness.
In 1970, Dr. Rahe conducted a follow-up study of 2500 sailors using the LCU scale and found a positive correlation between their stressful life events and subsequent medical issues.
The top ten life event and LCU values from the scale are:
|Life Event||Life Change Units|
|Death of a spouse||100|
|Death of a close family member||63|
|Personal injury or illness||53|
|Dismissal from work||47|
The following paragraphs will examine how stress does its dirty work and how we can make a few changes in our lifestyle to deal with the stress.
Stress and Health: The Physiology of Stress
Stress is now viewed as a “bad thing”, with a range of harmful biochemical and long-term effects. These effects have rarely been observed in positive situations.
Stress Definition: What is Stress?
The most commonly accepted definition of stress (attributed to Richard S Lazarus, a psychologist and pioneer in emotion and stress) is that stress is a condition or feeling experienced when a person perceives that “demands exceed the personal and social resources the individual is able to mobilize.”
In short, it’s what we feel when we think we’ve lost control of events.
Acute health effects are characterized by sudden and severe exposure. Normally, a single incident is involved. Acute health effects are often reversible such as in carbon monoxide or cyanide poisoning. Acute stress is usually sudden but temporary with the body returning to a state of balance (homeostasis) when the crisis passes.
Chronic health effects are characterized by prolonged or repeated exposures over many days, months or years. Symptoms may not be immediately apparent. Chronic health effects are often irreversible. Examples: lead or mercury poisoning, cancer.
Chronic stress, unlike health stresses, is not viewed as irreversible but does require special interventions to modify the behavior or perceptions underlying the ongoing stress response.
Stress and Health: The Effects of Stress, The Nun Study
Research has shown that lifestyle factors have a great effect on how humans handle and react to stress. It was noticed that groups of Catholic nuns living in some convents were living in excess of one hundred years with no signs of cognitive disorders, no Alzheimer’s or dementia. They were learning new skills and even new languages in their 90’s.
A 20 year study was done on the physiology of their longevity and many of them agreed to donate their brains to science upon their death.
The ones that did show signs of Alzheimer’s disease also showed signs of having experienced small strokes. This was another confirmation that the risk factors for Alzheimer’s and cardiovascular
The conclusions of the nun study suggest that significant cognitive decline is not a normal part of aging. The nuns studied lived a life conducive to being mentally healthy; they lived quiet, low stress lives with others whom they shared similar viewpoints, they were well read, exercised regularly and ate good nutrition.
The Effects of Stress
The stress response in humans has been well mapped and it goes directly to specific regions of the brain; four to be exact. Brain chemistry is at the heart of stress and health interactions.
The Amygdala, in the temporal lobe, is part of the brain circuit that equips us to respond quickly to a threatening situation: the well known “fight or flight” response.
The Hippocampus, also in the temporal lobe, is an area of the temporal lobe involved in learning and memory. It is an evolutionary old part of the cortex.
The pre-frontal cortex area appears to be critical in “unlearning” a behavior and even very small lesions (damage) in this area can prevent the unlearning or reversal of a learned response. In this case to key to fixing stress and health restoration may not work.
The reticular formation, in the brain stem, is a collection of neuron groups in the core of the brain that controls many vital functions including selective attention.
Neuroscience recognizes that the way in which we interpret and experience the world emotionally has a deep effect on both our physical and mental health. The traffic jam isn’t the problem; with stress and health, it’s all in how we respond to it.
Emotions guide us to make good or bad decisions so how do we harness that to our benefit?
A threatening situation activates the sympathetic nervous system, that part of the nervous system, under the control of the hypothalamus, which prepares us for fight or flight. The hypothalamus is a part of the brain involved in maintaining homeostasis or balance or “normality”.
When we are confronted by a saber tooth tiger who thinks we would make a great appetizer, the hypothalamus causes the release of a hormone, adrenocorticotropic (ACTH), from the pituitary gland. The pituitary is an endocrine gland about the size of a pea, located at the bottom of the hypothalamus at the base of the brain.
Its hormones serve to regulate other endocrine glands and have a role in regulating homeostasis (the “health” in the stress and health relationship).
Adrenal glands located above the kidney respond to ACTH by releasing catecholamines (neurotransmitter chemicals) and cortisol into the blood stream.
Cortisol is a corticosteroid hormone, often referred to as the “stress hormone” as it is involved in response to stress. It increases blood pressure and blood sugar, and reduces immune responses.
Peripheral Nervous System (PNS) catecholamines are dopamine and epinephrine and in the short term are useful responses. They enable a quick response, alertness and stimulate muscle.
When the saber tooth tiger is gone and the crisis is over; another part of the PNS under the control of the hypothalamus brings about a state of rest and relaxation. The PNS are parts of the nervous system that lie outside the brain and spinal cord.
Stress and Health – The Immune System
Chronically high cortisol levels cause a decrease in the body’s natural immune response. The whole immune system is designed to fight foreign invaders so if we are facing a saber tooth tiger, the immune system doesn’t need to worry about fighting a virus right at that moment. “Stress and health” suddenly becomes a matter of “stress and survival”.
Cortisol causes a decrease in the body’s desire to have the immune system work properly since we have to survive the tiger first and all the body’s resources need to be focused on that end. Cortisol also causes a chronic decrease in our DNA repair mechanism.
Little pieces of DNA is constantly getting damaged so when we are facing the tiger, the DNA repair mechanism is shut down as well; another aspect of “stress and health” taking backseat to “health and survival”.
In addition there is an increase in the autoimmune mechanism. This is where some part of the immune system goes awry and attacks its own body thus autoimmune diseases are very sensitive to chronic stress and health greatly suffers.
In summary, cortisol decreases the immune response, increases the autoimmune response and decreases the DNA repair mechanism.
The consequences are more colds, infections, cancer (no DNA repair), more autoimmune diseases such as multiple sclerosis (MS) in which the immune system attacks the neuron’s dendrites and myelin sheaths (insulation). Lupus and arthritis flare ups may start occurring among other things.
Stress and Health – The Cardiovascular System
The cardiovascular System is damaged by chronic stress in two ways: non-ischemic and ischemic. Non-ischemic refers to direct damage to heart muscle itself. The release of high levels of catacholamine, translates to high levels of epinephrine from the adrenal glands.
This was first noticed by NASA in heart attacks and the sudden death of astronauts from constant chronic stress. Besides the long term stress of a launch and space voyage, after every launch most astronauts would lose their job, causing more stress.
Abnormally high levels of cortisol and catacholamine were found to be the culprits and the mechanism has since been validated by inducing heart attacks in lab rats.
Ischemic damage is the result of a blocked blood supply to a structure. Blocked vessels to the heart cause heart attacks. Cortisol and epinephrine are responsible for scarring in blood vessel walls causing plaque buildup and eventual clotting. The same risk factors occur in Alzheimer’s disease.
To summarize, the stress system was designed to start and stop. Under acute conditions, there is no problem and we return to homeostasis.
The effects of chronic stress on brain
Chronically high levels of cortisol cause neuron death in the brain’s hippocampus. It was found that the hippocampus is especially sensitive to cortisol in that it has a very high number of cortisol receptors and binds cortisol. Why is there no problem on acute level? We don’t know yet.
When receptors are chronically bound, it sets up a cascade of events causing neuron death. Mitosis does not replace cells killed under these circumstances. The process Kills so many hippocampus neurons that the atrophy from it can be seen on MRI scans.
Long term emotional distress shows decreases in cognitive ability, especially memory; all because the hippocampus likes binding to cortisol.
Reduce Stress…Health Improves!
The problem is how do chronically stressed out or depressed people go about climbing out of the abyss of despair. Remember, we are talking about chronic, long term ongoing emotional trauma; stress and health are inseparable. It’s easy to say, “get happy” or “get over it” but gratuitous comments like these don’t help anyone.
If you want to learn how to relieve stress; go to your doctor and chances are you will walk out with any one of fifteen or so popular drugs for depression, anxiety and stress.
For a real stress reliever, try getting your hands dirty doing some backyard gardening. Plant some flowers, grow some herbs, watch the vegetables grow that you planted.
Great stress reducers are laughter, meditation, friendships and support groups, exercise and nutrition.
We will briefly touch on how these are beneficial to stress and health management without going into a great amount of detail on each one.
Laughter is great medicine. So much research has been done on its effects on stress and health that it will be covered in a separate page of this site. But until then, know that laughter has been proven to:
• lower blood pressure
• decrease the stress hormones discussed earlier
• rotects the cardiovascular system
• improves brain function
Exercise has many of the same benefits on stress and health as laughter and will likewise be covered in a separate page of the site.
The obvious beneficial effects of exercise are on the cardiovascular system and musculoskeletal system. In addition exercise has been shown to be very effective in combating depression and raising self-esteem.
Meditation provides several benefits for handling stress and health as well. It helps maintain the health of brain cells and preserve memory related functions which imply that it acts on the limbic system. The limbic system is an interconnected group of neuron cells that are involved in learning, memory and emotion.