CORTISOL – The stress hormone
Is our saviour turning into a killer in the third millennium?
Dr Sly Nedic
What is stress?
There is still no established definition in medical textbooks, but one current dictionary definition is:“the set of all organic reactions to physical, psychic, infectious, or other, aggressions, which are capable of disturbing homeostasis (internal body equilibrium).”
Our body is designed to react to stressful situations (eustress) by preparing it for fight or flight to survive. The primary stress hormone released during this situation is, alongside adrenalin, cortisol.
Cortisol is made from cholesterol in adrenal glands,produced according to a circadian rhythm that sees highest production in the morning and lowest during sleep.
During stress, at the expense of biological mechanisms not essential for immediate survival, cortisol facilitates those responses that are crucial for surviving imminent danger. These processes include: increasing the amount of glucose available to the muscles and brain (through gluconeogenesis), inhibiting insulin production to prevent glucose from being stored, increasing blood flow, and suppressing immunity.
The body is meant to return to an equilibrial state, without any hormonal imbalances, once the stressful situation has been resolved. This, however, does not happen in everyday life!
Ongoing stress has become such a part of our permanent state that many of us don’t even know what a fully relaxed state feels like. In fact, we use the word “stress” so often in our everyday lives to describe any situation that involves even the smallest amount of strain. Examples include everything from driving to work, answering emails, dealing with economic crises, long working hours, load-shedding and relationship difficulties to helping our children finish their school projects – just about everything we do has a stressful aspect to it.
Unfortunately, permanent stress stimulates continuous cortisol secretion,which leads to accelerated detrimental diseases that contribute to the world’s overall morbidity and mortality.
Contribution to insulin resistance
The escalating levels of counter-regulatory hormones to insulin (such as cortisol) are early features of insulin resistance, as these are the first to be released under stressful conditions. Regular stresswill stimulate a sustained release of higher levels of cortisol and other counter-regulatory hormones.
Maintaining blood glucose concentration homeostasis in a constantly stressful environment requires a shift in both baseline and postprandial (post-meal) insulin levels. Eventually, this reaches a point where the system starts to decompensate. The pancreas cannot maintain the production and secretion of insulin to counter the effects of the cortisol, and metabolic derangement becomes apparent as the four counter-regulatory hormones overpower the insulin.
As a result, a spectrum of types of insulin resistance can develop, which includes type 2 diabetes, lipid problems, cardiometabolic syndrome, polycystic ovarian syndrome, sleep apnea, depression, obesity, adult-onset acne, fatty liver disease and a predisposition to cancers (prostate, colon and breast).
One of the most dangerous “side effects” of stressful living and high cortisol is an increase in the size of visceral fat. There are four times more cortisol receptors in visceral fat than elsewhere, and cortisol is important in redistributing fat from other tissue to belly fat, as a mechanism for survival. A particular study showed that even lean women with high cortisol develop belly fat with underlying visceral fat. So next timeyou just can’t get rid of that abdominal fat that increases your waist-to-hip ratio, or struggle to fit into your favourite jeans despite exercising and eating right, cortisol may in fact be at the root of the matter. Visceral fat contributes to a higher risk of heart attack, cancer, obesity andinsulin resistance.
Cortisol can also contribute to weight problems by directly influencing appetite and cravings through binding to hypothalamus receptors in the brain and can indirectly affect appetite by modulating other hormones and stress-responsive factors known to stimulate appetite.
Immune system suppression is yet another significant effect ofthe ongoing cortisol release related to continual stress. Remember,cortisol “believes” we are inimminent danger and does everything to shut down any functionnot necessary for our immediate survival!
An unrestrained immune system responding to persistent inflammation (which is out of control during chronic stress) can lead to multiple problems, such as an increased susceptibility to colds and other infections, the tendency to develop food and other allergies, an increased risk of developing autoimmune diseases(Hashimoto thyroiditis, lupus, etc.), and a higher susceptibility to certain cancers.
Bad gut reaction
When a parasympathetic system (necessary for digestive functions) is switched off in stressed-out body, digestion is compromised in many ways: absorption is diminished, indigestion develops and the intestinal mucosa becomes inflamed. This inflammation leads to the increased production of cortisol, and the cycle continues – causing ulcers, leaky gut, irritable bowel syndrome, gut candida, bacterial infections and more.
Chronic stress eventually over-exhausts adrenal resources, contributing to chronic adrenal fatigue, which is manifested in the development of many other symptoms like fibromyalgia, anxiety, panic attacks, neurotransmitter misbalance and premature ageing.
Intervention and integrative approach
In order to address the numerous problems associated with stress and excess cortisol production, it is vital to understand the damaging effects thereof as well as take into consideration how lightly the majority of South Africans view this problem. Integrative medical physicians need to educate their patients about it, utilize the appropriate diagnostic tools and make use of a combination of anti-stress interventions, cortisol adaptogens and integrative medical approaches to combat this terribly harmful state.