What is Stress?
Stress is the body’s response to a change that requires a physical, mental or emotional adjustment. It is also the body’s method of reacting to or preparing for a new challenge. Stress can originate from any situation or thought that makes you feel concerned, nervous, frustrated or angry. Its effects on the body are not only psychological, but physiological as well.
The physiological reaction that occurs in response to a perceived threat happens via activation of the sympathetic nervous system. This results in a typical ‘fight-or-flight’ response. Besides the nervous system, various stress hormones are also released into the body. The immediate response is activated by the hormones such as adrenaline (epinephrine) and noradrenaline (norepinephrine), whilst cortisol controls the more long-term stress response.
What is cortisol?
Cortisol is a steroid hormone produced by the adrenal glands. Cortisol plays an important role in how the body uses food substrates such as carbohydrate, fat, or protein, in order to meet additional physiological demands. Cortisol is normally released in response to events such as waking up in the morning, during physical exercise and stressful events.
When chronically elevated, cortisol has a negative impact on many systems, including weight control and immune function. With a high stress, fast-paced lifestyle, the body ends up producing cortisol almost continuously. Whilst cortisol is essential to the body, too much cortisol can have a significantly detrimental effect on our health.
What effect does stress have on blood sugar levels and the development of diabetes?
Under stressful conditions, cortisol helps to provide the body with glucose by tapping into protein stores and helping to release the glucose that is stored in the liver. This energy is required in a typical fight or flight situation. However, elevated cortisol over the long term constantly stimulates the release of glucose, leading to increased blood sugar levels. Since a principal function of cortisol is to counteract the effects of insulin, it causes bodily cells to become insulin resistant. Over time, the pancreas struggles to keep up with the increased demand for insulin. The result is that glucose levels become elevated. Chronic stress therefore increases the risk for diabetes.
What effect does stress have on weight gain and obesity?
Chronic elevated cortisol levels can lead to weight gain. One mechanism is to stimulate the storage of fatty acids in fatty tissue contained inside the abdominal cavity. (Visceral fat stores). Another way goes back to the blood-sugar insulin problem. Consistently high blood glucose levels, in the presence of insulin resistance, leads to cells that are starved of glucose. Since these cells are in need of energy, they send hunger signals to the brain via a biochemical signalling mechanism. This leads to increased eating and the intake of excess glucose that is eventually stored in the body as fat. Cortisol has also been linked to cravings for high-calorie foods.
What effect does stress have on the immune system?
Cortisol, being a steroid hormone, is similar to the drug cortisone, often used by doctors to suppress inflammation in virtually all tissue types. In the body, cortisol’s ability to suppress inflammation is mostly beneficial. However, this may also lead to the suppression of the immune system, causing an increased susceptibility to colds, flu and other infections, as well as an increased risk to develop certain forms of cancer. Cortisol is also associated with a tendency to develop food allergies and an increased risk of various gastrointestinal disorders, since a healthy intestine is dependent on a functional immune system. The risk of developing an autoimmune disease is also higher.
What effects does stress have on the gastrointestinal system?
The ‘autonomic nervous system’ is the part of the body’s ‘automatic’ control mechanism that regulates various involuntary bodily functions, such as breathing, digestion and circulation. It consists of two divisions, namely the sympathetic and parasympathetic systems that, to a large degree, work in opposition to each other. When the sympathetic nervous system is ‘switched on’, the parasympathetic nervous system should ideally be ‘switched off’.
Whilst the sympathetic nervous system accelerates the heart rate, constricts blood vessels and raises blood pressure under stressful conditions, the parasympathetic nervous system does the opposite and helps to slow the heart rate, increase intestinal and glandular activity, and relax sphincter muscles.
The parasympathetic nervous system becomes more active during relaxed activities, such as eating. This is important because for the body to best use food energy, enzymes and hormones controlling digestion and the absorption of nutrients must be working at peak performance. Activation of the sympathetic nervous system by cortisol, however, results in the suppression of the parasympathetic nervous system. This compromises digestion and impairs the absorption of nutrients. As a result, indigestion and heartburn may develop and the mucosal lining of the gastro-intestinal tract may become inflamed. In response, mucosal inflammation of the stomach also leads to the increased production of cortisol, causing a vicious cycle. This is a reason why stomach ulcers are more common during stressful times. Those suffering from irritable bowel syndrome and inflammatory bowel disorders like ulcerative colitis also report an improvement in their symptoms when they master better stress management.
What effect does stress have on the cardiovascular system?
Through the activation of the sympathetic nervous system, cortisol constricts blood vessels and increases blood pressure in order to enhance the delivery of oxygenated blood during the fight-or-flight reaction. Over time, chronic arterial constriction also leads to high blood pressure and hardening of the arteries, which may cause heart attacks and stroke. This is one of the reasons why stressed-out personality types are at a greater risk for developing cardio-vascular disease.
What effect does stress have on fertility?
Elevated cortisol levels relating to prolonged stress can cause the disruption of menstrual cycles and ovulation, resulting in female infertility. Furthermore, the androgenic sex hormones are produced in the same glands as cortisol and epinephrine, so excess cortisol production may impair the optimal production of these hormones. Elevated cortisol levels are also known to cause erectile dysfunction.
What effects does stress have on fatigue?
Long-term stress and elevated cortisol levels are linked to insomnia, chronic fatigue syndrome, thyroid disorders, dementia and depression.
Which lifestyle changes can help to reduce stress?
Seeing that a chain is only as strong as its weakest link, the best way to manage stress is by using a combination of techniques. Start by eating a balanced, nutritious diet. Exercise regularly and avoid poisoning your brain and body with cigarettes, ‘recreational’ drugs and excessive alcohol intake.
Depending on your source of stress, there are various cognitive techniques that can be used to strategically plan, communicate and think better. These include techniques on how to manage conflict more effectively and how to put better boundaries in place between you and the people that cause you to become stressed.
In addition, we recommend the use a regular supplement to assist you during times of excess work load or emotional fatigue. Roseroot (Rhodiola rosea) is a perennial plant that grows at high altitudes in the Arctic regions of Europe and Asia. Extracts of the roots have been used in Scandinavian and European countries to combat fatigue, reduce the effects of stress and to aid convalescence during illness. Several psychometric tests conducted on subjects under pressure demonstrated a substantial reduction in fatigue-related symptoms and an improvement of various cognitive indicators that are medically associated with increased psychological stress. These include a recorded reduction in cortisol levels. Roseroot has a low side effect profile and is generally considered a safe and effective supplement.
References
- DSM IV Diagnostic criteria for acute stress disorder
- World Health Organisation Guidelines on conditions specifically related to stress, 2013
- American Institute for Preventative Medicine, General Stress Management, 4th edition 2012
