by Hannah Kaye"Essentially, we humans live well enough and long enough, and are smart enough, to generate all sorts of stressful events purely in our heads…if you are a zebra running for your life…your body’s physiological response mechanisms are superbly adapted for dealing with such short-term physical emergencies…When we sit around and worry about stressful things, we turn on the same physiological response…stress-related disease emerges, predominantly, out of the fact that we so often activate a physiological system that has evolved for responding to acute physical emergencies but we turn it on for months on end, worrying about mortgages, relationships and promotions."
1What is stress?Stress is not the actual events in your life. Stress is your body’s reaction to those events. When you are faced with a stressful situation, your body produces a "stress response" to give you the extra energy you need to deal with that situation. Hormones that are produced by the hypothalamus, pituitary and adrenal glands mediate this stress response.
The stress response is essential to life because it allows you to handle challenges posed by your environment. It can be a problem, however, when the stress response is triggered too frequently. In this case, your body continuously pumps out stress hormones, which can put you out of balance and deplete your body’s reserves. It is this chronic stress that makes you feel "stressed out" and can lead to numerous health problems, chronic disease and even shorten lifespan.
Hormones of the stress responseAs the master gland, the brain can experience or think something stressful and activate components of the stress-response hormonally.
Two hormones vital to the stress response are adrenaline and noradrenaline, released by the sympathetic nervous system. Another important class of hormones in the stress response are called glucocorticoids (e.g. cortisol). Secreted by the adrenals, they often act in ways similar to adrenaline. Adrenaline acts within seconds, glucocorticoids back up this activity over the course of minutes or hours.
The stress response is initiated by the release in the hypothalamus of corticotropin releasing factor (CRF). CRF triggers the release of adrenocorticotropic hormone, or ACTH, from the pituitary. After ACTH is released into the bloodstream, it reaches the adrenal glands and triggers glucocorticoid release. Together, glucocorticoids and the secretions of the sympathetic nervous system (adrenaline and noradrenaline) are the workhorses of the stress response.
Additionally, in times of stress, the pancreas is stimulated to release a hormone called glucagon. Glucocorticoids, glucagon and the sympathetic nervous system raise circulating levels of the sugar glucose. Other hormones are activated as well. The pituitary secretes prolactin, which plays a role in suppressing reproduction during stress. The pituitary also secretes vasopressin, which plays a role in the cardiovascular stress response.
Just as some glands are activated in response to stress, various hormonal systems are inhibited. The secretion of various reproductive hormones such as oestrogen, progesterone and testosterone are all inhibited.
It is because of all these hormonal changes that chronic stress results in problems such as insulin resistance, hypertension, infertility, redistribution of fat in the body, decreased protein synthesis and decreased DNA repair. Furthermore, the immune system is weakened through a decrease in the production of blood cells, antibodies, and gamma globulins.
What triggers a stress response?2There are four main categories of stress triggers, any of which can produce the same hormone-mediated response.1. Psychological triggers
2. Environmental triggers
- Chemical/toxin exposure
- Infection/allergens
- Intestinal Dysbiosis
- Noise
- Flashing light
- Vibration
3. Metabolic triggers
- Oxidative stress (free radicals)
- Inflammation
- Nutrient deficiency
- High sugar/high fat diets
4. Physiological triggers
- Accidents
- Surgery
- Burns
- Intense exercise
- Pain
- Poor sleep
Stress and ImmunityDuring times of acute stress your immune system is highly charged and various immune cells increase their production of chemical mediators or messengers ready to alert other immune cells into action if a potential infection or wound were to take place. During prolonged stress (from work, relationships, finances, hectic social schedules, exams, commuting) the high levels of chemical mediators actually start to have a more negative impact on other body cells due to their oxidizing nature and become capable of putting the body into a state of inflammation.
Stress has a direct impact on bacteria in the gut and may lead to dysbiosis. Gut dysbiosis may lead to a breakdown of GALT (gut associated lymphoid tissue) thereby instigating inflammation and autoimmune conditions. Food intolerances appear to be caused by gut dysbiosis (due to a dysregulation of regulatory T-cells which normally suppress an immune response to food).
Another consequence of prolonged stress is that the immune system eventually becomes exhausted and incapable of being resistant to all the infectious bugs that you come into contact with on a daily basis. This is why people who are under a severe amount of ongoing stress are constantly picking up low-grade infections such as cold sores, sore throats, colds, and even flu. By increasing the amount of antioxidant-rich foods in your diet such as berries, peppers, squashes, carrots and peas you can help to support your immune system and strengthen your resistance to infection.
Three eating tips to help break the stress cycle- Eat a protein rich breakfast every morning. Your brain and body run on fuel in the form of protein, fats, and complex sugars called carbohydrates. The brain’s energy comes primarily from sugar, and skipping breakfast causes an “alarm” that releases stress hormones. This in turn releases your body’s stored sugar in the liver and muscles to feed your "starving" brain—and makes you crave sugary foods and feeds the stress cycle. Your first meal of the day really is important—so eat well. Protein also helps you curb hunger longer, and won’t give you the "crash" that sugary foods like sweetened cereal or pastries do.
- Eat low-glycaemic whole-foods. Stick with whole-foods (nuts, wholegrains, raw fruits, vegetables) that are minimally processed – most of which have a lower glycaemic load and also a higher nutritional value.
- Eat small, frequent meals. Eating every 3-4 hours helps maintain blood sugar levels. Blood sugar highs and lows initiate a stress response.
Nutrients for combating stress | Nutrients | Their role | Foods to pick |
| Phosphorous | Levels are depleted in times of stress due to it being a major component of ATP (the usable form of energy) | Seafood, eggs, pulses, quinoa, nuts, seeds |
| Potassium | Required for the metabolism of proteins and various enzymes for the formation of energy from glucose | Avocados, tomatoes, sweet potatoes, cucumbers, peppers, bananas |
| Vitamin C | Required for adrenal function as it is utilized in the formation of adrenaline and cortisol | Fresh fruit and vegetables |
| Vitamin B5 | Used to make stress hormones. | Liver, poultry, yoghurt, avocados |
| Magnesium | Essential for adrenal gland function. | Oat bran, brown rice, quinoa, pumpkin seeds, nuts, dark green leafy vegetables |
| EFAs | They support the immune system and reduce inflammation. | Fish, nuts, avocadoes, seeds and their oil |
References
1. Institute for Functional Medicine. (2005) Textbook of Functional Medicine. IFM.
2. Sapolsky, M. (2004) Why Zebras Don’t get Ulcers. 3rd Edition. Owl Books.
