Stress is the experience of strain due to prolonged adverse circumstances. It regards attending to perceived threats that cannot sufficiently be dealt with. Over-stretching of bodily resources to meet some tasks forces the body to put other important activities on hold. This makes people feel under-par from attempts to cope with escalating demands and lack of rest. Stress always revolves around the limits of what can be managed – regardless of whether those boundaries are mental or physical. Although stress might not traditionally be considered an emotion, no account of emotions is complete without it.

To gain an up-to-date understanding of stress an appreciation is needed of how people psychologically, neuro-biologically and physically support good health. Homeostasis is the original word used to describe a process of “maintaining balance through change”, but it’s mainly used to refer to a limited number of bodily functions that are essential for life. The contemporary version of this concept is called allostasis.
Allostasis refers to how all systems – not just the ones essential for life – adjust the intensity of their activity while coping with perceived challenges and how those systems return to rest. Blood pressure, blood flow, catecholamine, and the secretion of cortisol are all involved in metabolic (chemical processes that support life) efforts to maintain normal body functioning. Allostasis specifically defines how many bodily systems adaptively use limited resources to support health. Part of the reason the term “allostasis” was coined was to distinguish a professional concept of stress for research. The concept gives considerable clarity to how the psychological and neuro-biological interactions are interwoven.
Allostatic-load refers to the wear and tear that’s experienced due to the processes of allostasis. The “load” refers to functional decline of internal organs and systems – especially the cardiovascular and endocrine – due to the arrangement of their work load. Internal constituents are stimulated thousands to millions of times to keep the body’s chemical constitution balanced for a healthy life. Amazingly, the overall number of times a system performs its operations throughout a person’s life is not the principal concern. Danger to health owes more to quantities of unsuitable and inappropriate responses. Serious problems are raised if one reaction is performed too much or too little. The body’s resources become preoccupied and cannot do other duties. Inappropriate turning on and shutting off of these processes disrupts the body’s ability to keep metabolic balance. When allostatic processes are overused or caused by maladaptive inaccurate perceptions, optimal balance cannot be maintained owing to complications from the added load.1

For example, especially over decades, excessive fight-or-flight reactions are firmly believed to be important for the slow progression of primary hypertension (high blood pressure) and metabolic syndrome in humans.2
The stresses people meet in early life (neglect and abuse are extreme stressors) interact with innate behaviour (genetic and epigenetic predisposition). These experiences are moulded into a unique set of psychological responses that can predispose people to overreact. Each disproportionate reaction is accompanied by an autonomic response. This includes the automatic secretion of hormones and neurotransmitters that prepare the body for the perceived threat. These over-the-top behaviours can become habitual ways of relating to perceived threats, particularly when learnt at a young age and repeated in adulthood.
Every time such an inappropriate defensive response is experienced it disrupts metabolic activity. Work load is added to the body’s schedule to keep a healthy internal balance. The amount of rest needed by a system within the body is increased. Another overreaction around the same time will deprive the body of the rest it needed to recover, and it will keep the body living in a state of deficit. The list of scheduled things to do is increasing and neglected. Ongoing bodily operations are performed by systems that are progressively deprived of rest and not working properly. These systems contain an increasing probability of interconnected failure.
There is a cascading effect from over-reactive and maladaptive autonomic responses, onto overworked systems, which places the body in an endless state of catch-up.

For example, chronic mental stress includes overworking several brain regions that cascade troublesome reactions. One such symptom of chronic stress seems to be the over-production of a chemical called calcitonin gene-related peptide or CGRP. This mass manufacture of CGRP envelops the surface of the Langerhans cells and reduces their functionality. It inhibits the Langerhans cells from detecting infectious agents and bringing them to the attention of the immune system’s white blood cells. Infections are then more likely to go undetected, compromise health, and create more work for the body while it has a reduced capacity to defend itself.3
Prolonged anxiety, sadness and despair can all suppress immune system functioning owing to similar cascades of neuro-biological processes. While depriving the body of much needed rest, excessive emotions interrupt and reduce the body’s ability to keep a healthy internal constitution. Thoughts and emotions are immersed in the allostatic procedures of maintaining balance through change. They work according to such fatigue and rest cycles.
Research is showing that the neurological functions of positive emotions are biassed towards the left-hemisphere, and the reverse is true for negative emotional functioning.4 This structural definition is part of a larger psychological architecture that underpins thought and emotional processes.

Negative emotions cause thought processes to become slower. They redirect attention onto perceived problems. People are forced to respond to red-alerts. Instincts orientate the body’s disposition with thought processes that best suit corrective behaviours.5 Negative emotions induce effortful focused analysis and vigilant thought processes. This creates a mentality focused on external processing that’s suited to solving problems, but it also keeps people in a tense mental, emotional and physiological state of alert. How long a person stays in a negatively affected state determines how stressed the systems involved in maintaining that state become.
Amygdalae, in the temporal lobes, receive perceptions from a wide range of cortical regions; they are a comprehensively interconnected part of brain functioning. When an event is perceived to be a potential threat – from any source of information, the amygdalae set in motion autonomic responses. People are then placed in a state of alert corresponding to a threat’s intensity and temporal closeness. If this process is activated too much, inappropriately or not, the systems responsible for carrying out the functions will become strained. This includes structural strains as noted by several studies that associate enlargement of the right amygdala with depression.6

In contrast, research shows that positive emotions make thoughts quick and responsive. Attention can switch from one subject to the next effortlessly. When experiencing positive emotions, attention uses current knowledge bases (i.e. memory). At the same time, an instinctive tendency to push unneeded analytical searching thoughts out of mind is present. When in a good mood, people naturally shy away from thinking about negative experiences. Judgements are more superficial and easy going. Psychological, neurological and biological pathways are taxed less. Positive moods form more flexible thoughts, which include a wider range of focus points, as attention is not narrowed as when negatively affected.

All this evidence proves that people’s ability to process social information changes according to what emotions are being experienced.7

The evidence-based theory, therefore, suggests that negative emotions direct attention towards a potential threat while adapting thought processes to accommodate searching for a solution to the problem. When the problem is solved, a positive emotion is experienced that induces thought processes towards current knowledge bases and away from external analytical thinking. The previously taxed right-hemisphere that was handling the negatively affective state releases the tension its systems were under, and they’re allowed to rest. This natural functioning indicates an allostatic process of maintaining balance through change.
Good health is not maintained by maximising positive emotions and minimising negative ones; it requires both negative and positive emotions to be applied appropriately.8 A mixture of fixing problems and resting needs to be respected. If not enough positive emotions are experienced, people might get stuck ruminating with analytical thought processes over problems that tax their systems, burdening them.

All living things support life by allostasis. The animals that are best at maintaining balance through change have organs, as part of a larger system, all dedicated to this process. Highly evolved animals sustain many body systems that themselves often encompass interconnected subsystems. The vast majority of all of these processes are instinctively carried out below conscious recognition.
Amassed over hundreds of millions of years, there’s far too much information being processed and applied, every minute of every day, to control consciously. In an evolutionary sense, humans have only just recognised the allostatic processes that have been responsible for maintaining the lives of all their ancestors. Consciousness is the most recent product of evolution. It gives humans the ability to reflect intellectually on self with high definition, but its processing power is limited to focusing on a few things at a time.
Stress is a wide reaching term and encompasses a vast amount of issues. This is a general description of stress. Just like conscious thought, it should be considered the tip of a large iceberg. Stress commonly arises from being over worked or having insufficient rest. Nevertheless, the narrative often includes other emotions that have become overwhelming to a detrimental degree. For example, the effects of loss and expected failure, on a daily basis, cause sadness and anxiety. These two emotions naturally prepare the host for certain eventualities, yet it’s possible for them to amass and have detrimental effects on the person in which they reside.
Emotions are good up to a point. They have to be an accurate reflection of circumstances to best help. Perception of an event is the defining factor. A looming failure, causing anxiety, could be real or unreal, yet if people believe a perception is true, they experience the associated emotion with its proper biological responses. Mistaken perceptions cause stress because people adapt their dispositions to them. As the real world also has to be dealt with, this introduces additional adaptations. Inaccurate perceptions increase allostatic-load.
A common form of stress is produced by having too many objectives to complete in a set amount of time. An example is when a person called Naive had forty-five hours in a week to get her scheduled work completed. She filled her weekly plan with forty-five hours of work and set appointments, but she forgot to include lunch breaks. A situation was created where she could not fulfil her commitments without injuring her health through lack of rest. She had a fifty hour timetable to do in forty-five hours. She would have to go the whole week with no lunch break to succeed. It would put strain on her life that could only be accommodated for a brief period. If it happened continuously, tension from prolonged activity, devoid of rest, would become too stressful, so it would lead progressively to ill-health.

Sometimes the term stress is used to place emphasis on negative emotions felt for a lengthy duration. People may fear negative things happening all the time. They can be sad about past losses whilst anxiously worrying about future injuries. Continuous negative emotions effectively drip-feed a cocktail of depressive neurotransmitters (onto nerves) and hormones (into the bloodstream) whilst keeping people constantly focused on their failures and fears. This affects their bio-chemical constitution (metabolism). As sleep patterns often become interrupted, people’s ability to recuperate is further decreased. The entire draining experience from these negative emotions and the inability to rest is termed stressful.
Feelings of lethargy can be incredibly debilitating for the unemployed, the depressed, the abused, and people living in constant fear and anxiety. Due to psychological elements such as anxiety, fear and sadness, this lethargic stress may be experienced without continuous physical activity, so it’s more easily overlooked. When they say how stressed and tired they feel all the time, people who suffer from depressive stress are met with surprise and suspicion. Even their friends and family may question whether they’re stressed at all – suspecting them of feigning their distress for sympathy. Thinking, “They haven’t got a busy work schedule or seem to do much of anything, so why should they be stressed?” rather than seeing it’s the lethargy caused by stress that keeps them from doing things.

Similarly, people can stand in disbelief that such lethargic stress is related to tooth decay and dental health issues in general. In the sceptic’s defence, the process is metabolic, so its progression does easily go unseen to the untrained eye. Nonetheless, the facts are compelling, and once learnt, they are irrefutable.
The process of dental decay is called “caries”. Bacteria form a bio-film over the surface of teeth as they metabolise carbohydrate substrate. The bio-film is made up of micro-organism communities, such as streptococcus bacteria, particularly in parts of the mouth that have a low pH level. When the bacteria metabolise carbohydrate substrate (most significantly all sugars), plaque forms as a by-product and the mouth becomes more acidic.9
The more acidic the mouth is, the more the bio-film communities flourish in demineralising the surface of teeth, leaving plaque deposits in their wake. Micro-colonies establish themselves more aggressively at plaque sites because pH levels are low in those places; tooth decay accelerates. Saliva naturally neutralises this process by effectively diluting acid and carbohydrate substrate, so raising the pH levels of the mouth. Thus saliva plays an important role in managing pH levels and the formation of concentrated plaque producing micro-colonies.
When the bacteria feed off sucrose – refined sugars, the process is most rapid as the actual sugar content is massively more than that of any naturally occurring sugar.10 This concentrated form of sugar is packed full of energy that the bio-film has evolved to exploit. The problem is that the unnatural doses mean that humans’ evolved salivary defence is insufficient for dissolving the by-product, hence plaque deposits build.
Saliva flow is at its lowest during sleep when it nearly stops. What is more, distinct bacterial micro-colonies form in a four to twenty-four hour window.11 When these two factors are considered together with refined sugar consumption, brushing teeth before sleeping is seen as vitally important to managing pH levels in the mouth. It is a hugely significant action in preventing tooth decay. This is why brushing twice a day and flossing is standard dental advice: it’s about dislodging the bio-film; especially with normal fluoride toothpaste, for it’s fluoridated at 1500 ppm, and fluoride at this harmless concentration makes it difficult for bacteria to demineralise teeth.12
Brushing before sleep disrupts the bacterial bio-film that’s formed during the day and prevents it from taking hold in the low pH hours. Because brushing in the morning disrupts the bio-film that’s developed whilst sleeping, the bacteria have to start over, and they only have a fourteen to sixteen hour window before their production is disrupted once again; thus bacteria are prevented from forming stubborn micro-colonies.
When this dental knowledge is applied to stress, significant problems are revealed. Lethargy of stress compels people to eat high energy foods – refined sugars – that take the least amount of energy to consume. As a result, pH levels in the mouth drastically drop, and streptococcus bacteria aggressively advance into distinct micro-colonies within twenty-four hours. At the same time, the lethargy of stress increases the likelihood of not brushing before sleep (the importance of the activity seems insignificant when compared to the stresses in mind), so bacteria formations are less likely to be disrupted before forming micro-colonies. As patches of plaque depositing micro-colonies remain intact for days, bacteria diversify. As bacteria’s metabolic activity creates acid which lowers pH levels, tooth decay accelerates specifically in colony spots. Sites of bacteria that cannot be removed by brushing and can only be seen with a mouth mirror easily form under such circumstances. A bout of lethargy that lasts several months can lead to cavity formations that appear many months after the experience. Therefore, stress is easily overlooked as significantly contributing to tooth decay.

Several decades have passed with attachment theory (which has amassed over sixty years of evidence-based research)13 persuading people to pay attention to the negative and positive emotions of children. The theory links with other approaches that discuss parenting styles that support emotional-coaching behaviours.14 Emotionally dismissive parents are largely characterised by dismissing emotional expressions altogether or encouraging positive emotions whilst discouraging negative ones. Negative emotions are more commonly shunned and may even be punished. A child might grow learning that emotions such as sadness, fear, and anger are emotions that only the weak, cowardly or “out of control” express. Given the evidence that suggests both negative and positive emotions are necessary for good health, it leads one to ask “What are the detrimental effects of non-expression of negative emotions?”

Theoretically, because negative emotional experiences are so strongly associated with problem solving, it suggests that stress would occur due to neglecting perceived threats – problems – that build to become overwhelmingly stressful. This fits with findings that show cognitively avoidant people, who ignore the thought of their feared thing, are more confident than people who think about an eventuality they fear. That is until the cognitively avoidant people’s feared event comes true. At which time, the cognitively avoidant become the most physiologically stressed, and they are more likely to experience psychological crisis (see Ignorance).15

Two of the ways problems build up and lead to crisis are as follows.

First, expressing negative emotions in social relationships is proven to give relief to those who express it, for it increases sympathy and empathy from those who care. It’s shown to make people more likable and deepen social bonds. People are far more likely to actively participate in collaborative problem-solving when they see a family member or friend expressing negative emotion.

Second, over the past fifty years, it has been repeatedly suggested that expression of emotion is an important element in coping with stressful circumstances. This is proving true. Studies show that people who suppress (conscious) and repress (subconscious) their emotions are more at risk of cancer onset than people who do not.16 Stress is also found to create high levels of cortisol and speed up disease progression.17 Raised cortisol over sustained periods is associated with system dysfunction and contributes to manifestation of serious health complications.18 Corticosteroids are also linked to tumours.19 At the same time, studies show that cancer patients who express negative emotions, especially anger, live longer.20 Bottling up emotion raises cortisol levels whilst reducing the natural communication that would lead to help from others.

Inexpression of negative emotions is a double whammy to regulating health, and this can be said with immovable conviction.
Although humans do not have a complete understanding of the inexpression of negative emotions, the accumulating evidence firmly associates it with the onset and progression of biological diseases. A scientific philosophical approach to emotional health is based on expression and not repression. It includes the social consequences of not expressing anger, such as letting abuses go unchallenged (see Anger). So it’s sound advice. Children should not have their negative emotions shunned or belittled. Repression of such emotions, over long periods of time, is proven to manifest serious health conditions, especially those connected with high cortisol levels.

On the other hand, oxytocin releasing behaviours – such as breast-feeding and cuddling – are highly associated with a sense of touch, affection and feelings of security (see Gratitude). Oxytocin is a hormone and neurotransmitter that has potent anti-stress effects (e.g. reducing blood pressure, heart rate and cortisol levels for potentially weeks at a time).21 It has been proven that the company of others can reduce cortisol levels.22 In epidemiological circles (the science of health and disease in populations) it has long been known that socially isolated people are more likely to get sick and die younger than their peers who have the company of a partner, friends or family.

Intense physical activities offer a way to refresh our systems, have concentration realign metabolic output, so effectively flushing build-ups of stress hormones and neurotransmitters (such as cortisol) as focus is placed on more immediate needs. This management should not be mistaken for a cure though, for it does not address the underlying causes, yet it can keep ill-health at bay while we do. All the above should lead researchers, in social health, to place considerable attention on habitual relationship conflicts as risk factors for progressive mental and biological health problems.23 Longitudinal research, over decades, shows that allostatic-load predicts incidents of cardiovascular disease, decline in physical functioning, and memory loss.24


Latin. Strictus = compressed, drawn tight.

1. Hardship, adversity, affliction.

2. Psychology and biology: an adverse circumstance that disturbs, or is likely to disturb, the normal physiological or psychological functioning of an individual; such circumstances collectively. Also, the disturbed state that results.

3. The overpowering pressure of some adverse force or influence: (a) force or pressure exercised on a person for the purpose of compulsion or extortion; to distress; (b) to do or make (a person) stress;; to press hardly upon; to oppress.