Cortisol: Friend or foe? Understanding benefits and limits of the ‘stress hormone’

Cortisol is vital for your wellbeing, but too much can be unhealthy.

Located on top of your kidneys, the adrenal glands release cortisol, a hormone. In biology, a hormone is any chemical messenger that travels through the bloodstream and affects some tissue. 

It is cortisol’s primary job to provide fuel to working cells, in this case glucose. Even though it is primarily a stress hormone, it is released throughout the day. We have the highest levels in the morning as we begin our day, and the lowest levels overnight as we sleep.

Normal levels in adults range between 30 and 145 nanomoles per liter per day [1]. In Cushing’s disease, which typically results from a tumor in the pituitary gland and causes increased cortisol levels, this range is bracketed by the highest levels. 

Addison’s disease, which is usually caused by damage to the adrenal glands, has the lowest levels. The importance of this hormone can be seen in Addison’s disease. 

Thomas Addison documented patients suffering from fatigue and muscle degeneration in the 1850s. The “adrenal extracts,” which included cortisol, were successful in treating these patients.

The majority of Addison’s patients died within two years of diagnosis before this discovery. Today, these patients can live normal lives by taking cortisol [2].

What does cortisol do?

Synthetic versions of cortisol, such as hydrocortisone, are used to reduce inflammation. Have you ever hiked through poison ivy? In a few days, the redness and swelling will go away if you rub some hydrocortisone on it. 

In addition to its anti-inflammatory effects, it also plays a role in maintaining health. During acute inflammation, it helps reduce it quickly, but it also enables the body to fight future inflammation.

Why would we want to decrease our cortisol levels? Cortisol illustrates the saying, “Moderation in all things.” A rapid cortisol response helps fight off an infection, but a prolonged elevation can cause health problems. 

Depending on the dose and timing of cortisol, it acts very differently. Inhibiting inflammation by diverting metabolic resources from the immune system is beneficial for the body.

We are more likely to get sick if our immune system is suppressed for a long period of time. In response to a stressful event, it fuels working muscles. As a result, we are able to cope with stress and survive quickly. 

After we have overcome the stressful event, the body continues to release cortisol. Alternatively, if the stressful event doesn’t end, and all the fuel our muscles need during stress starts to have detrimental consequences, like muscle wasting and suppressed immunity.

Is it beneficial or harmful? In the same way, glucose (sugar) in small doses is necessary for survival, but at higher levels can cause problems [3]. 

At high levels, it can damage, but it is also essential for survival and good health. You should keep this in mind when you try to balance your cortisol levels.


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