How the body reacts to prolong stress is described by Dr Hans Selye in terms of the General Adaptation Syndrome. Selye divides the stress response into three phases: Alarm Response, Adaptation and Exhaustion. The Alarm Response is the fight or flight response that prepares the body for immediate action. If the source of stress persists, then the body prepares for long term protection through the secretion of further hormones that increase blood sugar levels to sustain energy and raise blood pressure. This Adaptation phase, resulting from exposure to prolonged periods of stress, is common and not necessarily harmful but without periods of relaxation and rest to counter-balance the stress response, sufferers become prone to fatigue, concentration lapses, irritability and lethargy as the effort to sustain arousal slides into negative stress. Under persistent, chronic stress, sufferers enter the Exhaustion phase: mental, physical and emotional resources suffer heavily and the body experiences ‘adrenal exhaustion’, where blood sugar levels decrease as the adrenals become depleted, leading to decreased stress tolerance, progressive mental and physical exhaustion, illness and collapse.
Exposure to excessive stress results in hormonal imbalances, which can produce a variety of symptoms:-
Physical symptoms – changes in sleep patterns, missed heartbeats, fatigue, palpitations, changes in digestion, breathlessness, loss of sexual drive, headaches, infections, indigestion, tingling of hands and feet, aches and pains in various parts of the body, dizziness, sweating and trembling.
Mental symptoms – lack of concentration, panic attacks, memory lapses, difficulty in making decisions, disorientation and confusion.
Emotional symptoms – deterioration in personal hygiene and appearance, bouts of depression, impatience and irritability, fits of rage and tearfulness.
Behavioural symptoms – appetite changes, eating disorders, increased intake of alcohol and other drugs, nail biting, fidgeting, restlessness, hypochondria and increased smoking.
The term ‘cardiovascular’ refers to the heart and the body’s system of blood vessels. Cardiovascular disease is probably the most serious health problem that can be linked to stress – it is the most common cause of death in the UK and the USA. The primary causes of heart disease include smoking and high fat diets but stress is a significant contributory factor.
Adrenal hormones act to increase blood pressure; temporary rises in blood pressure present no threat to health but a frequent or perpetual state of high blood pressure can have a serious effect on health in the long term. High blood pressure is linked with the development of arteriosclerosis or hardening of the arteries. Arteriosclerosis is the result of the development of blood plaque in the arteries, which progressively narrows the pathway through which the blood flows. Eventually an artery can become blocked, leading to angina, stroke and heart failure.
The immune system protects the body from infection and fights viruses, harmful bacteria and cancer. Excessive stress can damage the immune system by affecting the thymus gland, which manufactures white blood cells for regulating immunity and also produces various immune related hormones. The stress reaction diverts resources to the main parts of the body that need to deal with stress, mainly the brain, heart and muscles. The immune system and other systems are deprived of resources. The thymus gland may shrink because of the hormones that are produced by the adrenal glands. This will also degrade the work done by the white blood cells, which will cause damage to the body’s ability to fight infection. As a result high stress can result in reduced resistance to common infections, such as colds, flu and herpes. Because certain types of white blood cells produced by the thymus are active in preventing the development of cancer cells in the body, any damage to the thymus may effect the bod’s ability to resist cancer.
Asthma is a respiratory disorder marked by the temporary constriction of the bronchi, the airways branching from the trachea to the lungs. Attacks are usually brought on by allergic reactions to antigens, such as grass and tree pollen, mould spores, fungi and certain foods but also may be caused by chemical irritants in the atmosphere or by infections of the respiratory tract. Susceptibility to an asthma attack is based on hyperactivity of the bronchial muscles, which constrict on exposure to one or any of these agents. Chronic stress reduces the efficiency of the adrenal glands, reducing the output of anti inflammatory and anti allergic adrenal hormones, which may make an asthma attack more likely.
Diabetes is caused by the inability of the body to metabolise sugar correctly, leading to excessively high levels of sugar in the blood. Sugar metabolism is the responsibility of the hormone insulin, which is secreted by the pancreas. Most diabetics can produce insulin but various factors limit the hormone’s efficiency, known as ‘insulin sensitivity’.
The release of adrenal hormones under stress can have a significant impact on blood sugar levels. Adrenaline causes sugar in the liver to be put into the blood stream and cortisol acts to reduce the metabolism of glucose by cells. Large amounts of cortisol act to decrease insulin sensitivity. High blood sugar levels are not dangerous in normally healthy individuals but chronic stress, combined with other factors such as obesity, act to increase the likelihood of developing diabetes.
Ulcers are frequently associated with stress, although no conclusive link has yet been demonstrated. Normally the lining of the stomach is covered with a layer of mucus to protect it from the digestive acids and enzymes used in the breaking down of food. Over time, chronic stress can stimulate the overproduction of gastric juices, which break down the protective mucus and act upon the walls of the digestive tract, resulting in ulceration. Ulcers usually occur singly in round or oval lesions; the erosions are usually shallow but can penetrate the entire wall, leading to hemorrhage and possibly death.
Many problems with the digestive tract, such as constipation, diarrhea and irritable bowel syndrome are linked to stress. The brain will send messages to the nerves in the digestive tract in the form of hormones. These messages will tell the intestinal muscles to expand or contract. Hormonal imbalances can cause alterations in intestinal function, such as spasms, constipation and diarrhea. Chronic stress tends to shut down the digestive system altogether, exacerbating intestinal problems.
Stress increases levels of toxicity in the body and contributes to hormonal imbalances, both of which have an effect on the skin. The visible effects of stress on the skin include:- acne, spots, skin diseases, eczema, excessive pallor and psoriasis.
Headaches are one of our most common afflictions and are normally caused not by disease but by fatigue, emotional disorders or allergies. Intermittent tension headaches are caused by worry, anxiety, overwork or inadequate ventilation. The most common type, a chronic tension headache, is often caused by depression. Brain tissue itself is insensitive to pain, as is the bony covering of the brain (cranium). The stimulation of the nerves of the cranium, upper neck and the membranous linings of the brain will cause headache pain. This stimulation can be produced by inflammation, by the dilation of blood vessels of the head or by muscle spasms in the neck and head. Headaches brought on by muscle spasms are classified as tension headaches: those caused by the dilation of blood vessels are called vascular headaches.
Migraine is the most common cause of vascular headache. Many things seem capable of triggering migraine attacks, including stress, fatigue, drugs and foods that contain substances that affect the blood vessels. Chronic headache may be physical symptoms of depression or other kinds of severe emotional problems.
Stress has a debilitating effect on the nerves in general and certain premenstrual symptoms may be aggravated by stress. Many sufferers of PMS have abnormal levels of the adrenal hormone aldosterone, which may account for some of the problems of excessive fluid retention and weight gain, breast tenderness and abdominal bloating. Further release of aldosterone caused by stress will exacerbate these problems.
Chronic stress can produce severe depression because of its debilitating psychological effects. The physiological changes produced by stress can also contribute to depression. Adrenaline and noradrenaline are not only adrenal hormones but chemical messengers in the brain. Deficiencies of noradrenaline have been linked to depression in certain individuals and so adrenal exhaustion through chronic long term stress may be a contributory factor in depressive illness.