The Centers for Disease Control and Prevention (CDC) estimates that up to 90% of all illness and disease is due to stress.
Stress is your body’s way of responding to any kind of demand or threat. Signs of the body under stress include irritability, fatigue, high blood pressure, impaired sleeping and insomnia. The effects of stress can be emotional, psychological, and physical.
Constant stress, if not treated, can lead to changes in behaviour (emotional eating, smoking, increased alcohol consumption) and a precursor to anxiety disorders, depression, PTSD (Post Traumatic Stress Disorder) and many chronic illnesses in the body.
When you feel threatened, your nervous system responds by releasing a flood of stress hormones, including adrenaline and Cortisol, which activates the flight or fight centre of the brain (the amygdala) to rouse the body for emergency action.
Cortisol is a steroid hormone produced by the adrenal gland and secreted during a stress response. As a part of the body’s fight-or-flight response, Cortisol also acts to suppress the body’s immune system.
Serotonin is a neurotransmitter thought to play an important role in mood regulation. Stress-induced serotonin dysfunctions have been associated with anxiety, fear and depression-like symptoms.
Stress can kill the good bacteria and yeast that live in your intestines and keep your immunity and digestive health strong. More research is showing how stress impacts the function of your gut every day.
It slows transit, leading to constipation and the re-circulation of hormones like estrogen through your liver. It increases the overgrowth of bad bacteria. And it loosens the barriers between the cells that line the intestines, creating something called leaky gut that then leads to inflammation, food sensitivities and even autoimmune disease.
Studies have also shown that the activity of hundreds of genes responsible for enzymes that break down fats and detoxify prescription drugs, are negatively impacted by stress. Stress can also increase your toxin burden by increasing your desire for high fat, high sugar foods.
Stress is the body’s reaction to any stimuli that disturbs its equilibrium. When the equilibrium of various hormones is altered the effect of these changes can be detrimental to the immune system.
Stress affects the immune system in many ways. The immune system protects the body from viruses, bacteria, and anything that is different or that the body does not recognize. The immune system sees these as intruders and it sends messages to attack. The white blood cells, leukocytes, are very important to the immune system.
The white blood cells, leukocytes, are very important to the immune system. These leukocytes produce cytokines which fight infections. But they also are the immune systems communicator in telling the brain that the body is ill.
When an individual is stressed or going through a stressful experience the immune system starts to produce natural killer cells and cytokines. When levels of cytokines are higher they combat infections and therefore the brain gets communicated the body is ill and it produces symptoms as if the individual was ill.
These symptoms include fever, sleepiness, low energy levels, no appetite, and flu like symptoms. These symptoms mean the body is fighting the illness or virus. This is useful for when the body goes through the stress from an injury.
But unfortunately, the body has now evolved to do this process during stressful events such as taking exams, or even going through a life changing event such as a death of a family member or a divorce. That is why many times when individuals are stressed because of life changing events or situations such as those, they get these symptoms and believe they are sick when in reality it can be because the body is under stress.
Both negative and positive stressors (endurance sports) can lead to stress, the intensity and duration of stress changes depending on the circumstances and emotional condition of the person suffering from it. Some common categories and examples of stressors include:
Sensory input such as pain, bright light, noise, temperatures, or environmental issues such as a lack of control over environmental circumstances, such as food, air and/or water quality, housing, health, freedom, or mobility.
Social issues can also cause stress, such as struggles with difficult individuals, social defeat, relationship conflict, deception, or break ups, and major events such as birth and deaths, marriage, and divorce.
Life experiences such as poverty, unemployment, clinical depression, obsessive compulsive disorder, heavy drinking or insufficient sleep can also cause stress. Students and workers may face performance pressure stress from exams and project deadlines.
Adverse experiences during development like prenatal exposure to maternal stress, poor attachment (abandonment) histories and sexual abuse) are thought to contribute to deficits in the maturity of an individual’s stress response systems.
Stages of Stress
Physiologists define stress as how the body reacts to a stressor (real or imagined) which is a stimulus that causes stress. Acute stressors affect an organism in the short term; chronic stressors over the longer term.
General Adaptation Syndrome (GAS), developed by Hans Selye, is a profile of how organisms respond to stress; GAS is characterized by three phases: a nonspecific mobilization phase, which promotes sympathetic nervous system activity; a resistance phase, during which the organism makes efforts to cope with the threat; and an exhaustion phase, which occurs if the organism fails to overcome the threat and depletes its physiological resources.
Alarm is the first stage, which is divided into two phases: the shock phase and the anti-shock phase.
Shock phase: During this phase, the body can endure changes such as the stressor effect.
Anti-shock phase: When the threat or stressor is identified or realized, the body starts to respond (Cortisol) and is in a state of alarm (flight or fight).
Resistance is the second stage and increased secretion of glucocorticoids play a major role, intensifying the systemic response—they have lipolytic, catabolic and antianabolic effects: increased glucose, fat and amino acid/protein concentration in blood.
In high doses, Cortisol begins to act as a mineralocorticoid (the steroid hormone aldosterone which maintains salt level in the body) and brings the body to a state similar to hyperaldosteronism (excessive secretion of aldosterone).
If the stressor persists, it becomes necessary to attempt some means of coping with the stress. Although the body begins to try to adapt to the strains or demands of the environment, the body cannot keep this up indefinitely, so its resources are gradually depleted.
The third stage could be either exhaustion or recovery.
Recovery follows when the system’s compensation mechanisms have successfully overcome the stressor effect (or have completely eliminated the factor which caused the stress). The high glucose, fat and amino acid levels in blood prove useful for anabolic reactions, restoration of homeostasis and regeneration of cells.
Exhaustion is the alternative third stage in the GAS model. At this point, all of the body’s resources are eventually depleted and the body is unable to maintain normal function. The initial autonomic nervous system symptoms may reappear (sweating, raised heart rate, etc.).
If stage three is extended, long-term damage may result (prolonged vasoconstriction results in ischemia which in turn leads to cell necrosis), as the body’s immune system becomes exhausted, and bodily functions become impaired, resulting in decompensation.
The result can manifest itself in obvious illnesses, such as peptic ulcer and general trouble with the digestive system (e.g. occult bleeding, melena, constipation/obstipation), diabetes, or even cardiovascular problems (angina pectoris), along with clinical anxiety, panic attacks, depression and other mental illnesses.
Chronic stress is defined as a state of prolonged tension from internal or external stressors, which may cause various physical manifestations – e.g., asthma, back pain, arrhythmias, fatigue, headaches, HTN, irritable bowel syndrome, ulcers, and suppress the immune system.
Chronic stress takes a more significant toll on the body than acute stress does. It can raise blood pressure, increase the risk of heart attack and stroke, increase vulnerability to anxiety and depression, contribute to infertility, and hasten the aging process.
People in distressed marriages have also been shown to have greater decreases in cellular immunity functioning over time when compared to those in happier marriages.
Furthermore, during chronic stress, Cortisol is over produced, causing fewer receptors to be produced on immune cells so that inflammation cannot be ended.
Chronic stress has been shown to increase the thickness of the artery walls, leading to high blood pressure and heart disease.
Chronic stress also increases the production of Cortisol, leading to something called “Cortisol steal,” where fewer sex hormones are produced.
Chronic stress is seen to affect the parts of the brain where memories are processed through and stored. When people feel stressed, stress hormones get over-secreted, which affects the brain.
That is because stress releases Cortisol, and Cortisol causes metabolic activity throughout the body. Metabolic activity is raised in the hippocampus. High Cortisol levels can be tied to the deterioration of the hippocampus and decline of memory that many older adults start to experience with age.
Post-traumatic stress disorder (PTSD)
PTSD is a severe anxiety disorder that can develop after exposure to any event that results in psychological trauma. This event may involve the threat of death to oneself or to someone else, or to one’s own or someone else’s physical, sexual, or psychological integrity, overwhelming the individual’s ability to cope. As an effect of psychological trauma, PTSD is less frequent and more enduring than the more commonly seen acute stress response.
Diagnostic symptoms for PTSD include intrusion, avoidance and hyper-arousal — re-experiencing the original trauma(s) through “flashbacks” or nightmares (intrusion), emotional numbing or avoidance of stimuli associated with the trauma, and increased arousal, such as difficulty falling or staying asleep, anger, and hyper-vigilance.
Formal diagnostic criteria (both DSM-IV-TR and ICD-10) require that the symptoms last more than one month and cause significant impairment in social, occupational, or other important areas of functioning.
The areas of the brain affected in post-traumatic stress disorder are sensory input, memory formation and stress response mechanisms. The regions of the brain involved in memory processing that are implicated in PTSD include the hippocampus, amygdala and frontal cortex. While the heightened stress response is likely to involve the thalamus, hypothalamus and locus coeruleus.
Cortisol works with epinephrine (adrenaline) to create memories of short-term emotional events; this is the proposed mechanism for storage of flash bulb memories, and may originate as a means to remember what to avoid in the future. However, long-term exposure to Cortisol damages cells in the hippocampus; this damage results in impaired learning. Furthermore, it has been shown that Cortisol inhibits memory retrieval of already stored information.
Atrophy of the hippocampus in post traumatic stress disorder
There is consistent evidence from MRI volumetric studies that hippocampal volume is reduced in posttraumatic stress disorder (PTSD). This atrophy of the hippocampus is thought to represent decreased neuronal density. However, other studies suggest that hippocampal changes are explained by whole brain atrophy (partial or complete wasting away) and generalised white matter atrophy is exhibited by people with PTSD.
The psychiatric diagnosis post-traumatic stress disorder (PTSD) was coined in the mid-1970s, in part through the efforts of anti-Vietnam War activists and the Vietnam Veterans against the War, and Chaim F. Shatan. The condition was added to the Diagnostic and Statistical Manual of Mental Disorders as posttraumatic stress disorder in 1980.
PTSD was considered a severe and ongoing emotional reaction to an extreme psychological trauma, and as such often associated with soldiers, police officers, and other emergency personnel.
The stressor may involve threat to life (or viewing the actual death of someone else), serious physical injury, or threat to physical or psychological integrity including sexual abuse, domestic violence, workplace and schoolyard bullying, or a serious accident.
In some cases, it can also be from profound psychological and emotional trauma, apart from any actual physical harm or threat. Often, however, the two are combined.
Many areas of the brain appear to be involved in depression including the frontal and temporal lobes and parts of the limbic system including the cingulate gyrus. However, it is not clear if the changes in these areas cause depression or if the disturbance occurs as a result of the etiology (branch of medical science concerned with the causes and origins of diseases) of psychiatric disorders.
In depression, the hypothalamic-pituitary-adrenal (HPA) axis undergoes upregulation with a down-regulation of its negative feedback controls and Cortisol is released from the adrenal glands; adrenal hypertrophy (excessive growth) can also occur.
Release of Cortisol into the circulation has a number of effects, including elevation of blood glucose. The negative feedback of Cortisol to the hypothalamus, pituitary and immune system is impaired. This leads to continual activation of the HPA axis and excess Cortisol release. Cortisol receptors become desensitized leading to increased activity of the pro-inflammatory immune mediators and disturbances in neurotransmitter transmission.
Serotonin transmission from both the caudal raphe nuclei and rostral raphe nuclei is reduced in patients with depression compared with non-depressed controls. Increasing the levels of serotonin in these pathways, by reducing serotonin reuptake and hence increasing serotonin function, is one of the therapeutic approaches to treating depression.
In depression the transmission of noradrenaline is reduced from both of the principal noradrenergic centres – the locus coeruleus and the caudal raphe nuclei. An increase in noradrenaline in the frontal/prefrontal cortex modulates the action of selective noradrenaline reuptake inhibition and improves mood. Increasing noradrenaline transmission to other areas of the frontal cortex modulates attention.
How to Control and Reduce Stress
There are several ways of coping with stress such as controlling the source of stress or learning to set limits and to say “no” to some of the demands that bosses, partners or family members may make.
A way to control stress is first dealing with what is causing the stress… if it is something the individual has control over. Other methods to control stress and reduce it can be: to not procrastinate and leave tasks for last minute, do things you like, exercise, do breathing routines, go out with friends, and take a break. Having support from a loved one also helps a lot in reducing stress.
A person’s capacity to tolerate the source of stress may be increased by thinking about another topic such as a hobby, listening to relaxing music, spending time in nature, or participating in meditation or yoga classes.
Hypnotherapy is also a very powerful way to reduce stress build up in the body by teaching the body how to naturally handle and process stress.