Impact of stress and fatigue on health

Stress leads to fatigue and health issues that can range from headaches to heart issues, digestive problems, and immune deficiency. According to a Mayo Clinic report8, psychological stress can be one of the most significant factors responsible for future cardiac complications, including myocardial infarction (MI) and sudden death. The economic burden of hospitalisations as a result of high and low stress in these patients was approximately $9504 and $2146 respectively. The normative ageing study9–11 shows that dramatic emotions such as anger, anxiety, and worry that accompany stress are high risk factors for coronary heart disease (CHD) and MI.

Stress and fatigue occur in sequential order. In the healthy individual, the stress response is physiologically initiated by the sympathetic nervous system and is known as the flight and fight response. Sympathetic modulation of stress is achieved through the release and increased availability of stress hormones, such as adrenaline, noradrenaline and cortisol. In the body’s attempt to enter adaptive mode, the stress response is ideally dampened with the help of inhibitory neurotransmitters such as serotonin and gamma‑aminobutyric acid (GABA). The chronic stress of a fast-paced world eventually depletes both excitatory and inhibitory neurotransmitter supplies, resulting in drowsiness, lack of energy, and lack of motivation. To compound the issue, multiple factors such as lack of sleep, poor nutrition, infection, or other physical and psychological causes lead to the body’s inability to replete stores to adequate levels, leading to burnout or exhaustion. This combination of multiple symptoms for more than 6 months with certain key features comprises the diagnosis of CFS.

Physiology of stress and fatigue

Sources of modern stress and fatigue are manifold and include calorie restriction, surgery, sleep deprivation, excessive exercise, and stressful mental states. Regardless of the source, all stress results in the elevation of cortisol and catecholamines. Studies12,13 demonstrate that the physiological and psychological consequences of acute and chronic stress can continue even after the cessation of the stressful event, including alteration of the circadian rhythm of cortisol secretion.

Initially, the acute stress event activates the hypothalamic pituitary adrenal axis and causes levels of cortisol to increase. The hypothalamus, also known as the master gland of the body, initiates the sympathetic response by releasing corticotrophin releasing factor (CRF), which signals the pituitary gland to release adrenocorticotropic hormone (ACTH), which in turn stimulates the adrenal glands to release cortisol. With the rise of cortisol levels a negative feedback mechanism instructs the hypothalamus to stop the release of CRF.

The physiological changes of stress include hypertension, tachycardia, and elevated blood sugar. Digestive problems may occur because of redirection of blood away from the stomach and an overactive sympathetic system releasing large amounts of cortisol and adrenaline. Once these episodes are chronically repeated, neurotransmitter and hormone reserves are depleted, leading to persistent fatigue. Prolonged fatigue beyond 6 months is called chronic fatigue and eventually, burnout syndrome. The interplay between prolactin, dopamine, serotonin, and cortisol may also play a role in the development of fatigue and burnout.

[pull_quote align=”left” ]Fatigue is often a result of nervous system impairment. There is often an underlying chemical imbalance of neurotransmitters and hormones, which constitute the body’s most important chemical messenger systems.[/pull_quote] Fatigue is not usually permanent and individuals do not suffer from extreme or persistent symptoms. It usually subsides after getting adequate rest or recovering from an illness. But for another group of individuals fatigue symptoms persist throughout their entire day, regardless of the amount of sleep obtained. Fatigue is often a result of nervous system impairment. There is often an underlying chemical imbalance of neurotransmitters and hormones, which constitute the body’s most important chemical messenger systems. In particular, imbalances in hormones as well as brain chemicals called neurotransmitters can be an underlying component to the development of fatigue. Neurotransmitters are chemicals that relay signals between nerve cells, called ‘neurons’. They are present throughout the body and are required for proper brain and body functions.

Every neurotransmitter behaves differently. Some neurotransmitters are inhibitory and tend to calm, while others are excitatory and stimulate the brain. Health professionals conclude that specific neurotransmitter imbalances are more likely to underlie certain conditions. Deficiencies involving the central nervous system’s neurotransmitters — adrenaline and noradrenaline — appear to be involved in the development of symptoms of fatigue. Disruptions in the stress hormone cortisol have been more closely linked with fatigue symptoms. Fatigue can impact normal cognitive function adversely. Symptoms may range from lack of concentration, difficulty focusing, and impaired memory. In addition, individuals commonly complain of malaise, troubled sleep, muscle pain, headaches, sore throat, and tender lymph nodes. Serious health problems, including fatigue, can occur when neurotransmitter levels are either too high or too low.

Environmental and biological factors — including stress, poor diet, neurotoxins, or genetics — can cause imbalances in the levels of neurotransmitter chemicals in the brain. These imbalances can trigger or exacerbate fatigue. Most pharmaceutical medications used to treat fatigue and CFS actually focus on other symptoms. For example, many address sleeping difficulties, cognitive problems, pain, and additional symptoms that correspond with CFS. These medications primarily support neurotransmitters such as serotonin, noradrenaline, and GABA.

Neurotransmitter function can also be supported with nutrient-based programmes. Neurotransmitters are made from a variety of components found in the food of a normal, healthy diet. Increasing the amounts of these dietary constituents can help to maintain normal neurotransmitter levels.