Cortisol 101: How the “get-out-of-bed” hormone works (and what happens when it doesn’t)

Cortisol is a hormone you’ve probably heard of. But when it comes to what cortisol does day to day, few of us know more than the fact that it has something to do with stress.

WellTuned spoke with Dr. John Calvin Channell, a medical director for BlueCross BlueShield of Tennessee, to learn more.

What is cortisol?

Dr. Channell: Cortisol is a hormone that’s primary role is to manage how your body uses carbohydrates, fats and protein. Along with your brain, it helps control your mood, fear and motivation. Cortisol is made by your adrenal glands. These are triangle-shaped organs above each kidney.

In general, cortisol:

Helps us manage the metabolism of carbs, fats and proteins
Boosts energy for stress management
Reduces inflammation
Manages blood sugar
Controls the sleep-wake cycle
Maintains balance in energy use and energy supply

Cortisol is sort of the “keep-everything-stable” hormone. Cortisol levels are highest in the early morning and lowest in the evening. This is why it’s also sometimes called the “get-out-of-bed” hormone.

How is cortisol related to stress?

Dr. Channell: In people who are stressed — whether it’s from an injury, surgery or other physical stress — cortisol helps us manage and recover from that stress. When your body is on high alert, cortisol can even shut down functions that get in the way, such as digestion, reproduction or the immune system.

Is cortisol related to the “fight-or-flight” response?

Dr. Channell: Not really. Those hormones (epinephrine, norepinephrine, adrenaline) come from the adrenal glands, and so does cortisol. But cortisol’s role in fight-or-flight is actually to help you calm down after the adrenaline is no longer needed.

How is cortisol connected to inflammation?

Dr. Channell: One function of cortisol is decreasing white blood cell response. This action helps reduce inflammation. Cortisone medications mimic the action of cortisol but tend to be more powerful. Common synthetic equivalents of cortisone include:

Hydrocortisone, which is used to treat redness, swelling, itching and other skin conditions
Glucocorticoids, which are used to treat rheumatoid arthritis, inflammatory bowel disease (IBD), asthma and allergies

Is there anything you can do to ensure healthy cortisol levels?

Dr. Channell: Problems with cortisol are complex to diagnose. Cortisol is controlled by a complex feedback system. Your hypothalamus, pituitary and adrenal glands all work together to regulate it. So it takes more than a standard blood draw to know if something’s off.

The good news is that you don’t have to do anything if your cortisol is functioning as it should. But if you notice any of the symptoms above, contact your healthcare provider.

What health conditions can cortisol levels cause?

Dr. Channell: Cortisol is difficult to pin down. We can look at what happens when you don’t have it, or when you have too much. But cortisol levels speak more about when things are going wrong than when everything is okay.

Addison’s disease

Addison’s disease occurs when you don’t have enough cortisol. It causes:

Extremely low blood pressure
Diabetes
Obesity
Fatigue
Loss of appetite
Nausea, vomiting and diarrhea
Muscle weakness

Dr. Channell: If you don’t have enough cortisol, you don’t even want to get out of bed. You may have a general rundown feeling. This can look like depression, as well as other personality changes.

Another side effect of Addison’s disease is darkening of the skin. Remember how people used to talk about President John F. Kennedy having such a great tan? Well, it wasn’t from the sun; it was Addison’s disease.

Cushing’s disease

Dr. Channell: Cushing’s disease, on the other hand, is what happens when your body has too much cortisol.

Symptoms of Cushing’s disease are:

Rapid weight gain
Easy bruising
Muscle weakness

Both Cushing’s and Addison’s cause muscle weakness though. This is why each requires specialized testing to diagnose.

Ashley Brantley

Ashley Brantley has been writing about food, culture and health for more than a decade, and has lived in three of Tennessee’s four major cities (Memphis, Nashville and Knoxville).