Stress - Back to Basic

Stress is simply too broad a term to be fully understood and categorised.
Already, you have read in previous articles that stress can take many forms and can be the result of many different stimuli (environmental or internal), but also that it can generate various physiological changes or symptoms depending on its chronicity.
But what is stress, and how can it be defined? 
Only by answering these simple questions that we will be able to finally understand it.

Bruce S. McEwen writes in the Journal of psychiatry and neuroscience (2005. pp. 315–316):
 
“Stress is a constant factor in modern life and a frequent topic of conversation. Yet in spite of its frequent use, the word “stress” is at best an ambiguous term. For some, it means excitement and challenge (“good stress”); for many others, it reflects an undesirable state of chronic fatigue, worry, frustration and inability to cope (“bad stress”). For this latter situation, I prefer the term “stressed out,” which implies the chronic nature of a negative state. To allow more precision in the discussion of stress, my colleagues and I have introduced new terminology and a new conceptual framework focused on the biologic mechanisms used in coping with stress and the central role of the brain. This new framework distinguishes between the protective and damaging consequences of the response to stressors.” Adding: “Stressors of all varieties were initially thought to ignite a general and diffuse arousal reaction in the body. Through the enormous progress that has been made in biomedicine over the past half century, a very different picture of integrative physiology has emerged — one in which the social environment has a cumulative impact on physical and mental health and the progression of a number of specific diseases. This effect of the social environment results from the fact that the brain and the body are in 2-way communication via the autonomic nervous system and the endocrine and immune systems. It is these systems that provide protection and allow adaptation in the face of acute stress, yet they also contribute to the negative impact of chronic stress and an unhealthy lifestyle. Thus, rather than “stress,” an ambiguous term that has both good and bad connotations, what most people are most concerned with when they talk about stress is the state of being “stressed out.”
 
   Usually, A fast heartbeat, a racing mind, and difficulty in sleeping or staying asleep (not reaching deep sleep cycles) are all signs of stress – being “stressed out” – and anxiety. With our stressful busy modern lifestyles, it is not really surprising that many of us experience these signs at any time during our lives.
 
   We have our bodies hardwired: primitive instincts that prepare us for “flight or fight” in life-threatening circumstances and that are responsible for a good deal of the stress and anxiety in modern life. If attacked by an animal in the wild, the sudden rush of the hormone adrenalin released in the body would be very useful in preparing our muscles to run away! Our modern stress equivalents to being chased by a predator (being late for work or arguments) may be less life-threatening but create the same surge of hormones that circulate in high level throughout the body in order to stimulate immediate mental and physical responses.
   During prolonged stress, when still remaining on “red alert”, the brain can also signal for the adrenal glands to produce stress hormones such as cortisol. Cortisol is a hormone released over a longer period of time and may be increased due to fairly common circumstances (lack of sleep, unmanageable workload or financial worries). Sustained high cortisol production can lead to high blood pressure and a tendency to store fat around the middle; this is particularly common in men (“fight or flight” may apply to men only, while “tend-and-befriend” applies to women)1.
 
   Any form of stress in the short term is considered harmless for health; indeed, it is a natural process our bodies are designed to deal with, which then return to normal; but if stress persists over a long period of time, this may result in constant activation of the body’s stress response, i.e. chronic stress. During the release of stress hormones, our major organs such as heart and muscles are ramped up (higher blood pressure and energy delivered to muscles), but organs that are less vital during episodes of stress, such as the skin and digestive system, may be switched off. After periods of prolonged stress, this can eventually negatively impact the health of our skin, resulting in worsening of conditions such as psoriasis, and digestion may be sluggish during long-term stress, or diarrhoea or constipation may result in cases of anxiety or immediate stress.
 
   Every system of the body responds to acute challenge with Allostasis leading to adaptation. When these acute responses are overused or inefficiently managed, allostatic overload results.
   In the brain, secretion of the stress hormones adrenalin and cortisol in response to an acutely threatening event promotes and improves memory for the situation so that the individual can stay out of trouble in the future; however, when the stress is repeated over many weeks, some neurons atrophy and memory is impaired, whereas other neurons grow and fear is enhanced.
   In the immune system, acute stress promotes immune function by enhancing movement of immune cells to places in the body where they are needed to defend against a pathogen, yet chronic stress uses the same hormonal mediators to suppress immune function.
   In the cardiovascular system, getting out of bed in the morning requires an increase in blood pressure and a reapportioning of blood flow to the head to allow a person to stand up without fainting. Blood pressure rises and falls during the day as physical and emotional demands change, providing adequate blood flow as needed. Yet repeated elevation of blood pressure promotes generation of atherosclerotic plaques, particularly when combined with metabolic factors that damage the coronary artery walls.
   For metabolism, glucocorticoids (so named because of their ability to promote conversion of protein and lipids to usable carbohydrates) serve the body well in the short run by replenishing energy reserves after a period of activity, like running away from a predator. Glucocorticoids also act on the brain to increase appetite for food and to increase locomotor activity and food-seeking behaviour, thus regulating behaviours that control energy input and expenditure.
   This effect is useful during manual labour or when playing active sports, but it is not beneficial when someone grabs a pizza and a beer while watching television or writing a paper, particularly when these activities may also be generating psychological stress.
   Inactivity and lack of energy expenditure create a situation where chronic elevation of glucocorticoids released in the bloodstream, resulting from poor sleep, ongoing stress or as side effects of a poor diet, can impede the action of insulin to promote glucose uptake. Thus, whether it is psychological stress or sleep deprivation or a inadequate diet that is increasing the levels of glucocorticoids, the consequences in terms of allostatic load are the same — insulin resistance and increased risk for cardiovascular disease.
 
Causes
Although some stressors are unavoidable, supporting your brain with optimum nutrition and making lifestyle changes to reduce the impact of stress on the body, can take you a long way on your journey to a peaceful mind.
A calm state of mind and time to relax are often perceived as quite a luxury these days, but they provide crucial balance to the fast-paced way we mostly live. Whenever you feel overwhelmed, simply close your eyes and take deep breath, concentrating on the air filling your lung, take a short pause (5 seconds) and exhaling, blowing out the pressure of the day.
 
Symptoms
The way our bodies deal with stress can affect us in many different ways. Stress can result in symptoms as wide-ranging and diverse as feeling overwhelmed (by ‘everyday’ situations), heart palpitations, tiredness due to disturbed sleep or a total lack of sleep, feeling physically and mentally exhausted, digestive issues, skin problems, anxiety and, in severe cases, panic attacks.
   It is extremely common to have at least one of these symptoms if you have regular stressors in your life, especially if you are consuming refined foods, or if your diet is lacking in feel-good or brain-supporting nutrients.
 
FOOD
It may seem surprising (for far too many people) that the foods we eat can alter our stress levels, however when studying the effects foods have on hormone production and neurotransmitter (brain chemical messenger) function, it is clear that our diets can have a huge impact on how stressed we may feel.
 
Carbohydrates and glycaemic index (GI)
During times of stress, with cortisol production high, the resulting rush of glucose to the blood (for the flight or fight response) requires the pancreas to release a hormone called insulin in an attempt to quickly level out the blood sugar levels, back to a healthy amount. If, during chronic stress, you consume refined carbohydrates such as white bread, sugar, biscuits or crisps, this also requires fast insulin production as refined carbohydrates are very easy to break down in the body; cortisol, however, may hinder this due to efforts to keep blood sugar levels raised. If stress and cortisol production are already high, refined carbohydrates then put additional strain on the pancreas, possibly increasing blood sugar levels.
The speed at which a carbohydrate is broken down in the body, thereby determining the effect on blood sugar levels, is the glycaemic index (GI). Fast-releasing foods such as sugar have a high GI, and real whole foods containing fibre and protein such as brown rice, pulses, oats, nuts and vegetables have a lower GI. Choosing low GI foods is therefore a great option to keep insulin levels controlled. Low GI whole foods also have the added bonus of including a higher density of brain-supporting nutrients such as zinc and B vitamins. Staying away from highly processed foods will help to give your pancreas a rest, and will allow your blood sugar to level out, helping you out of the overly alert and stressed state.
 
Protein for brain chemical messengers
Consuming high quality protein daily (whether meat- or plant-derived) is essential for neurotransmitters to function optimally
If you are regularly experiencing stress and feel an inability to relax and calm your mind, this could be due to low production and impaired function of neurotransmitters in the brain. Neurotransmitters are the brain chemical messengers, which help you to experience feelings of relaxation and pleasure, improve your memory and ability to learn, and support quality of sleep.
As amino acids are required as the building blocks to synthesise neurotransmitters, protein intake in your diet may have a significant effect on neurotransmitter levels. Try to include good quality sources of protein to support neurotransmitter production, such as meat, fish, eggs, cheese, beans, lentils, yoghurt, nuts and seeds. If you are unsure how much protein to eat throughout the day, approximately 0.8 g per kg body weight is a reasonable intake for a healthy individual, and slightly higher at around 1 – 1.5g per kg body weight may be optimal for brain health, especially if you are very physically active which increases requirements. 75g of protein per day would be a good amount for a 75kg individual.
 
Fatty acids for brain function
Fatty acids, in particular the omega-3s EPA and DHA, are required in the body for optimum neurotransmitter function, supporting the ability to feel relaxed and calm and to improve sleep. The brain is particularly rich in omega-3 fatty acids; therefore requirements are high to keep cell membranes elastic and responsive to these neurotransmitters. Low blood levels of omega-3 EPA and DHA are therefore, not surprisingly, associated with anxiety.
The richest source of omega-3 EPA and DHA is oily fish, such as salmon, herring, anchovies and mackerel. Fish also has the added benefits of nutrients, including zinc and B vitamins, required by enzymes in the body to produce neurotransmitters. As oily fish almost inevitably contain toxins such as methyl mercury, if consuming more than 3-4 portions of oily fish a week, try to consume smaller fish lower down in the food chain, such as anchovies. Aim to eat at least two portions of oily fish per week. To give your body a higher dose of omega-3 EPA and DHA without unwanted toxins, good quality fish oil supplements are a safe option. Fish consumption has also been shown to significantly reduce heart rate variability and anxiety. (9)
For vegetarians, plant sources of omega-3 such as Flax/Linseed oil can be converted in the body to omega-3 EPA and DHA, although this conversion needs healthy, functioning enzymes in the body, requiring a good supply of zinc, magnesium and vitamin B6 in particular.
Other fatty acids found in foods such as nuts and seeds, avocados, olives and coconut are a healthy addition to your diet to support general brain health, so try to include these too.
 
Lifestyle tips
There are many other factors to consider alongside diet, which may also impact on your ability to measure stress. Caffeine, alcohol, cigarettes and drugs may also worsen long-term symptoms like anxiety, which are related to stress.
Moderate exercise may help to reduce stress, although more intense exercise has actually been shown to increase production of cortisol, so don’t overdo it at the gym if your body is already stressed out. Gentle and more relaxing exercises such as walking, swimming, yoga and Pilates are great for reducing stress levels – by reducing production of cortisol, reducing blood pressure and maintaining a healthy heart rate. Other relaxing practices such as reading a book, or even having a long soak in the bath, can help us to feel calmer and more balanced.
 
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Key Nutrients

Omega-3 EPA and DHA
As cell membranes are almost completely made of fats, it is not surprising that the brain is particularly rich in omega-3 long-chain fatty acids EPA and DHA. These important fatty acids help to keep cell membranes more elastic, allowing an optimal flow of neurotransmitters. These neurotransmitter brain chemical messengers, such as dopamine, allow you to feel pleasure and feel happy and relaxed, thereby stabilising emotions. Healthy functioning neurotransmitters are therefore a must for your brain to receive these anti-stress messages. Omega-3 EPA and DHA supplementation has shown very positive results in reducing anxiety symptoms.
 
Antioxidants
Antioxidants are the wonderful protectors for our cells against oxidative damage. During episodes of stress, oxidation in the body may be raised, and your organs working in overdrive to deal with stress such as the adrenal glands, will have an increased requirement for these antioxidants.
 
Vitamin C, vitamin E and selenium are very powerful antioxidants that are able to recycle each other in the body, therefore when taken together they have a stronger effect. A high intake of antioxidants from a range of foods such as peppers, berries and dark green leafy vegetables is ideal; during times of stress, however, it can be very difficult to obtain sufficiently high quantities to support your body if you are under so much pressure that you don’t prepare healthy meals from scratch each day. An extra antioxidant boost in supplement form can benefit many individuals who feel that they need additional support to deal with stress. Very high doses of vitamin C are required by the adrenal glands to support hormone production.
 
B vitamins
In times of stress, our requirements for B vitamins are very high and processed foods are commonly lacking in these vitamins. Keep up a good intake of rich food sources including fish, nuts, seeds, and green leafy vegetables such as spinach and kale. B vitamins are required in the body for many functions, including the proper functioning of enzymes to support essential processes such as production of neurotransmitters. Vitamin B5, for example, is required for healthy metabolism of choline, needed for the production of the neurotransmitters melatonin and acetylcholine, which help with sleep quality by regulating circadian rhythms. Supplementing with B vitamin complex has been shown to significantly lower personal strain and dejected mood; it may therefore help in reducing workplace stress.
Vitamin B6 in combination with zinc and magnesium are used throughout the body as a ‘team’, to support fatty acid metabolism and to be used by enzymes to support neurotransmitter production, for mood and concentration, and should all be taken in combination during stress. Magnesium also promotes relaxation and good quality sleep, so is very beneficial for anyone experiencing anxiety. Vitamin B6 combined with magnesium has been shown to reduce anxiety-related PMS symptoms.
 
L-theanine
L-theanine is an amino acid, naturally found in green tea, which has a natural calming effect on the body, reducing physical and mental stress. L-theanine acts as a relaxant by interacting with the neurotransmitter gamma-aminobutyric acid (GABA), which specifically helps to reduce anxiety and promote sleep.
 
Vitamin D
Most of us in the UK do not have optimum levels of vitamin D, mainly because vitamin D cannot be synthesised from sunlight in this country during the months of September to March. Vitamin D deficiency is associated with depression, low mood, and difficulty in sleeping. If stress or anxiety is linked to low mood and lack of sleep, vitamin D is an important one to remember.

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References
 
McEwen, BS. (2005). Stressed or stressed out: What is the difference? Journal of psychiatry and neuroscience. 30(5), pp. 315–318.
Purnell, JQ. et al. (2009). Enhanced cortisol production rates, free cortisol, and 11beta-HSD-1 expression correlate with visceral fat and insulin resistance in men: effect of weight loss. The American Journal of Physiology - Endocrinology and Metabolism. 296(2), E351–E357.
Steptoe, A. et al. (2004). Effort-reward imbalance, overcommitment, and measures of cortisol and blood pressure over the working day. Psychosomatic Medicine. 66(3), pp. 323–329.
Thorslund K, Amatya B, Dufva AE, Nordlind K. The expression of serotonin transporter protein correlates with the severity of psoriasis and chronic stress. Arch Dermatol Res 2013 Mar; 305(2):99-104.
Han B. Correlation between gastrointestinal hormones and anxiety-depressive states in irritable bowel syndrome. Exp Ther Med 2013 Sep; 6(3):715-20.
Choi S, Disilvio B, Fernstrom MH, Fernstrom JD. Meal ingestion, amino acids and brain neurotransmitters: effects of dietary protein source on serotonin and catecholamine synthesis rates. Physiol Behav 2009 Aug 4; 98(1-2):156-62.
Li M, Sun F, Piao JH, Yang XG. Protein requirements in healthy adults: a meta-analysis of nitrogen balance studies. Biomed Environ Sci 2014 Aug; 27(8):606-13.
Colombani PC, Mettler S. Role of dietary proteins in sports. Int J Vitam Nutr Res 2011 Mar; 81(2-3):120-4.
Liu JJ, Galfalvy HC, Cooper TB, Oquendo MA, Grunebaum MF, Mann JJ, et al. Omega-3 polyunsaturated fatty acid (PUFA) status in major depressive disorder with comorbid anxiety disorders. J Clin Psychiatry 2013 Jul; 74(7):732-8.
Hansen AL, Olson G, Dahl L, Thornton D, Grung B, Graff IE, et al. Reduced anxiety in forensic inpatients after a long-term intervention with Atlantic salmon. Nutrients 2014 Dec; 6(12):5405-18.
VanBruggen MD, Hackney AC, McMurray RG, Ondrak KS. The relationship between serum and salivary cortisol levels in response to different intensities of exercise. Int J Sports Physiol Perform 2011 Sep; 6(3):396-407.
Kiecolt-Glaser JK, Belury MA, Andridge R, Malarkey WB, Glaser R. Omega-3 supplementation lowers inflammation and anxiety in medical students: a randomized controlled trial. Brain Behav Immun 2011 Nov; 25(8):1725-34.
Stough C, Scholey A, Lloyd J, Spong J, Myers S, Downey LA. The effect of 90 day administration of a high dose vitamin B-complex on work stress. Hum Psychopharmacol 2011 Oct; 26(7):470-6.
De Souza MC, Walker AF, Robinson PA, Bolland K. A synergistic effect of a daily supplement for 1 month of 200 mg magnesium plus 50 mg vitamin B6 for the relief of anxiety-related premenstrual symptoms: a randomized, double-blind, crossover study. J Womens Health Gend Based Med 2000 Mar; 9(2):131-9.
Kimura K, Ozeki M, Juneja LR, Ohira H. L-Theanine reduces psychological and physiological stress responses. Biol Psychol 2007 Jan; 74(1):39-45.