Stress a normal part of life-I

Stress is a fact of nature in which forces from the inside or outside world affect the individual, either one’s emotional or physical well-being, or both. The individual responds to stress in ways that affect the individual, as well as their environment. Due to the overabundance of stress in our modern lives, we usually think of stress as a negative experience, but from a biological point of view, stress can be a neutral, negative, or positive experience.

In general, stress is related to both external and internal factors. External factors include the physical environment, including your job, your relationships with others, your home, and all the situations, challenges, difficulties, and expectations you’re confronted with on a daily basis. Internal factors determine your body’s ability to respond to, and deal with, the external stress-inducing factors. Internal factors which influence your ability to handle stress include your nutritional status, overall health and fitness levels, emotional well-being, and the amount of sleep and rest you get.

Stress has driven evolutionary change (the development and natural selection of species over time). Thus, the species that adapted best to the causes of stress (stressors) have survived and evolved into the plant and animal kingdoms we now observe.

Man is the most adaptive creature on the planet because of the evolution of the human brain, especially the part called the neo-cortex. This adaptability is largely due to the changes and stressors that we have faced and mastered. Therefore, we, unlike other animals, can live in any climate or ecosystem, at various altitudes, and avoid the danger of predators. Moreover, we have learned to live in the air, under the sea, and even in space, where no living creatures have ever survived. So then, what is so bad about stress?

A brief history of stress

A key to the understanding of the negative aspects of stress is the concept of milieu interieur (the internal environment of the body), which was first advanced by the French physiologist Claude Bernard. In this concept, he described the principles of dynamic equilibrium. In dynamic equilibrium, constancy, a steady state (situation) in the internal bodily environment, is essential to survival. Therefore, external changes in the environment or external forces that change the internal balance must be reacted to and compensated for if the organism is to survive. Examples of such external forces include temperature, oxygen concentration in the air, the expenditure of energy, and the presence of predators. In addition, diseases are also stressors that threaten the constancy of the milieu interieur.

The neurologist Walter Cannon coined the term homeostasis to further define the dynamic equilibrium that Bernard had described. He also was the first credited with recognizing that stressors could be emotional, as well as physical. Through his experiments, he demonstrated the “fight or flight” response that man and other animals share when threatened. Further, Cannon traced these reactions to the release of powerful neurotransmitters from a part of the adrenal gland, the medulla. (Neurotransmitters are the body’s chemicals that carry messages to and from the nerves.) The adrenal medulla secretes two neurotransmitters, epinephrine (also called adrenaline) and norepinephrine (noradrenaline), in the response to stress. The release of these neurotransmitters leads to the physiologic effects seen in the fight or flight response, for example, a rapid heart rate, and increased alertness.

Hans Selye, another early scientist who is known for his studies of stress, extended Cannon’s observations. He included the pituitary gland, a small gland at the base of the brain, as part of the body’s stress response system. He described how this gland controls the secretion of hormones (for example, cortisol) that are important in the physiological response to stress. Additionally, Selye actually introduced the term stress from physics and engineering and defined it as “mutual actions of forces that take place across any section of the body, physical or psychological.”

In his experiments, Selye induced stress in rats in a variety of ways. He found typical and constant psychological and physical responses to the adverse situations that were imposed on the rats. In rats exposed to constant stress, he observed enlargement of the adrenal glands, gastrointestinal ulcers, and a wasting away (atrophy) of the immune (defense) system. He called these responses to stress the general adaptation (adjustment) or stress syndrome. He discovered that these processes, which were adaptive (healthy, appropriate adjustment) and normal for the organism in warding off stress, could become much like illnesses. That is, the adaptive processes, if they were excessive, could damage the body. This observation, then, was the beginning of an understanding of why stress, really overstress, can be harmful, and why the word stress has earned such a bad name.

What are the signs and symptoms of poorly managed stress?

Excess stress can manifest itself in a variety of emotional, behavioural, and even physical symptoms, and the symptoms of stress vary enormously among different individuals. Common somatic (physical) symptoms often reported by those experiencing excess stress include sleep disturbances or changes in sleeping habits (insomnia or sleeping too much), muscle tension, muscle aches, headache, gastrointestinal problems, and fatigue. Symptoms of many preexisting medical conditions can also worsen during times of stress. Emotional and behavioural symptoms that can accompany excess stress include nervousness, anxiety, changes in eating habits including overeating or under-eating (leading to weight gain or loss), loss of enthusiasm or energy, and mood changes, like irritability and depression. Of course, none of these signs or symptoms means for certain that there is an elevated stress level since all of these symptoms can be caused by other medical and/or psychological conditions.

It is also known that people under stress have a greater tendency to engage in unhealthy behaviours, such as excessive use or abuse of alcohol and drugs, cigarette smoking, and making poor exercise and nutritional choices, than their less-stressed counterparts. These unhealthy behaviours can further increase the severity of symptoms related to stress, often leading to a “vicious cycle” of symptoms and unhealthy behaviours.

The experience of stress is highly individualised. What constitutes overwhelming stress for one person may not be perceived as stress by another. Likewise, the symptoms and signs of poorly managed stress will be different for each person.

Who is most vulnerable to stress? What are the risk factors for stress?

Stress comes in many forms and affects people of all ages and all walks of life. No external standards can be applied to predict stress levels in individuals - one need not have a traditionally stressful job to experience workplace stress, just as a parent of one child may experience more parenting stress than a parent of several children. The degree of stress in our lives is highly dependent upon individual factors such as our physical health, the quality of our interpersonal relationships, the number of commitments and responsibilities we carry, the degree of others’ dependence upon us, expectations of us, the amount of support we receive from others, and the number of changes or traumatic events that have recently occurred in our lives.

However, it is possible to make some generalisations. People with adequate or strong social support networks report less stress and overall improved mental health in comparison to those without adequate social support. People who are poorly nourished, who get inadequate sleep, or who are physically unwell also have a reduced capacity to handle pressures and stresses of everyday life and may report higher stress levels. Some stressors are particularly associated with certain age groups or life stages. Children, teens, the newly married, working parents, single parents, and seniors are examples of the groups who often face common stressors related to life transitions.

- medicinenet.comto be continued