Cortisol - A Brief Introduction

20th Oct. 2015

As humans throughout the years we have evolved to survive the conditions we were faced with.  A major factor in our survival is our body's ability to react to a stress.  In ancestral times our stress would usually come in a physical form, be that running from a predator or another human.  With todays lifestyle stress cloaks itself in many forms, mental and chemical stressors are constantly attacking our body and I find that you can link these particular aggressors to a lot of diseases as well as mental and physical obstacles. 

Often people become disheartened when following generic routine/nutrition plans and see no results.  I find it is usually the simplest of changes that can make all the difference in feeling and looking good.  An example is cortisol and a typical stress response, I am going to provide a brief overview on this process and the hormone cortisol and how it could be effecting you, your health and your progress towards any goals.

Cortisol falls into a category of steroid hormones.  Steroid hormones are responsible for a variety of bodily procedures like immune system functions and metabolism control to name a few.  Cortisol falls further into a sub category called glucocorticoids which is a large group responsible for many things like inflammation control and metabolism.  Cortisol becomes involved in the stress response as follows. 

There are two parts of this journey to fight or flight mode.  One response is suited to a short term stressor called the acute stress response and the other is because of a continuous stimulus telling the brain it is constantly in danger called the chronic stress response.  The following explanation is in relation the the chronic stress response.  Both responses start in a part of the brain called the hypothalamus.  Once the amygdala (also in the brain) signals to the hypothalamus that a stressful situation is occurring the hypothalamus then releases corticotropin to the pituitary gland (part of the endocrine system positioned at the bottom of the brain) which signals a chemical messenger into the blood stream called ACTH or Adrenocorticotropic Hormone.  

Once this messenger reaches the adrenal cortex (adrenal glands attached at the top of the kidneys), a variety of hormones are released one of them is epinephrine also know as adrenaline.  This increases the heart rate in preparation for action, contracts blood vessels so that blood can be sent primarily to the muscles, the digestive system slows digestion/production of enzymes amongst other processes making us optimal for combat or fleeing.  One of the hormones also in the blood now is cortisol, once cortisol is into the blood stream it floods the body with glucose so that the muscles have an immediate energy source, this will also inhibit insulin production to prevent the sudden rush of energy being stored.  This is all great if you were about to fight. But we are not.....

This brief explanation of the stress response is happening to people every second of the day most of which are not started by being chased by a tiger!  Its caused by bills, deadlines, horrible work colleagues and so on. You see this process will be readily available to your body always, but we need to control when it happens.  Easier said than done, I know, this is why it is important to manage your stress and the factors you can control like food, drink and exercise will play a major part in this. A good example of managing stress can be compared to a tiger charging at you, that would be a stress but knowing when and where is called managing your stress. 

Blood sugar levels is something you have some control over which have a link with body fat storage.  Food choices will influence blood sugar levels and when it is high and glucose is in your blood from a sugary snack or a stress response, if you are not actually being chased by a predator that ready supply of glucose/immediate energy running through your blood will be stored usually in the form of fat cells!  Now combine continuous spikes of blood sugar with continuous spikes via stress then those poor adrenal glands can only keep up the act for so long.  Meanwhile your pancreas, which creates insulin, (insulin regulates blood sugar levels bringing them back down to normal levels) will also get tired of being overused.  Say hello to either adrenal fatigue or diabetes both of which statistically are at all time high levels.

One of the most important aspect of our recovery from daily activity is sleep, our sleep is being effected by our daily choices and circumstances.  Cortisol is not always bad, it plays a necessary role in many bodily procedures, one of which is our cortisol clock.  When sunlight reacts with our pupils usually around 4am our cortisol levels naturally rise in preparation for our awakening, these levels should naturally fall during the day and our sleep hormones should start to produce when night falls.

One of these hormones is melatonin (melatonin is produced by the pineal gland in the brain), but with cortisol still usually so high its no wonder most people have trouble sleeping. 

Jamie Farrell is a Yazoomer community Premium advertiser. Check out details of his personal training and fitness company here