Cortisol, the Master Hormone behind Stress

Stress is an inevitable aspect of life. We encounter minor threats through the multiple demands we face each day, such as carrying a huge workload and making ends meet. These things make you feel you’re constantly under assault.


Everyone knows that feeling when you have your hands trembling and legs shaking when you audition for a play or difficulty sleeping while you worry about the approaching deadlines.  It means you’re under stress, and this is how your body reacts. While we are all familiar with the symptoms of stress response, not everyone knows the underlying physiological mechanisms.

The Stress Hormone, Cortisol

Stress triggers a series of physiological effects in our body. When your brain perceives a stressor, a part in your brain called hypothalamus releases cortisol. The hormone goes to your bloodstream and locks into receptors in your tissues and organs. What happens is that your blood sugar elevates, your heart rate increases and oxygen fills your muscles. Your body prepares itself for a threat, which is the evolutionary reaction known as “fight or flight”.


Many stress physiologists believe that a certain degree of cortisol indicates a healthy response – a cortisol level that fluctuates normally in response to stress and relaxation. A rhythm that is responsive and variable is good. For example, cortisol levels should be low at night or when you’re in a relaxed state. It normally tends to elevate during acute stress, during physical activity, or when meeting a work deadline. From high levels, cortisol should recover to baseline levels quickly.

When Your Body is Chronically Exposed to Cortisol

Once a perceived threat has passed, hormone levels return to normal. As cortisol levels drop, your heart rate and blood pressure return to baseline levels, and other systems continue their regular activities.


However, it is unhealthy if your body is chronically exposed to cortisol (whether high, medium or low levels). When stressors are always present and you constantly feel under attack, that fight-or-flight reaction stays turned on.


If your stress response system is activated in long term and you’re subsequently exposed to cortisol, your body processes get disrupted. You’re becoming more susceptible to several health problems including anxiety, depression, digestive problems, heart disease, sleep problems, weight gain and impaired memory and concentration.


Does It Mean Cortisol is Evil?

Although cortisol is known as a stress hormone, it doesn’t mean it is always bad. Cortisol is a life sustaining hormone that is essential to the maintenance of homeostasis. It plays a huge role in regulating many of the changes that occur in your body. These changes include blood sugar levels, macronutrient metabolism, immune responses, anti-inflammatory actions, blood pressure, heart and blood vessels tone and contraction, and nervous system activation.


Normally, cortisol levels fluctuate throughout the day and night. Although it is important to increase cortisol during stressful situations, it is also important that the body functions and cortisol levels return to normal once a stressful situation is over.


So far, it may seem as though stressed people are likely bound for failed health. Fortunately, there is much we can do to manage stress and keep cortisol in their normal levels. For some simple ways you can obliterate stress, click here.