Finally Understand How the Stress Hormone Cortisol Affects You


If you’ve reached out to a health practitioner or even just Googled what could be causing symptoms like fatigue, irritability, anxiety, unexplained weight loss or gain, and appetite changes, you’ve probably heard about the hormone cortisol. 
Since cortisol has influence on so many functions of the body, it can be a confusing thing to hear about.
Sound familiar? This article is for you! 
We’ll delve into what cortisol is, it’s role in your body, what affects cortisol and what happens when it gets out of balance.
To understand what cortisol is, let’s back up and talk about hormones first.

Hormones and Their Role in Your Body

Hormones are molecules produced and distributed by the endocrine system in your body. After they’re released into the blood, they’re carried to other parts of the body where their job is to communicate with different cells to elicit certain responses. 
Cortisol belongs to a specific group of hormones called steroid hormones, which are produced by the adrenal glands and gonads. Other steroid hormones include androgens, estrogen, progesterone, and aldosterone.
So what makes them steroid hormones?
Steroid hormones are different from non-steroid hormones because they are fat-soluble. That means they can cause changes within a cell by first passing through the cell membrane. 
They then enter the nucleus, bind to DNA and initiate gene transcription and protein production! (Source)
That’s what makes hormones so powerful—and why you will definitely notice when they are out of whack.

How the Stress Hormone Cortisol Works

Cortisol is commonly known as the stress hormone because it plays an important role in helping the body respond to—you guessed it—stress. 
Additionally, it regulates a wide range of processes throughout the body, including metabolism and the immune response.  
Almost every cell has receptors for cortisol! It’s role changes depending on what cells it is communicating with.
Our cortisol levels naturally rise and fall. Healthy cortisol levels will be higher in the morning and gradually decline throughout the day. And when our primal “fight or flight” response is triggered, cortisol rises to respond. 
However, when cortisol levels become high or too low for long periods of time, it can wreak havoc on the body in many ways and sometimes points to a disorder of your adrenal glands.

What Happens When You Become Stressed

When there is a threat perceived by your hypothalamus, it sends signals to your nerves and hormones. This triggers the release of cortisol (the primary stress hormone) and adrenaline by the adrenal glands.
Let’s paint a picture of what happens in your body when this surge of cortisol is released.
Circulating blood sugars increase to become available for the brain to use it. Other substances become available for the body to use to repair tissues.
Nonessential functions are limited. For example, immune system responses, digestive system, the reproductive system and growth processes are suppressed. 
This is what you’ll probably be most aware of—cortisol communicates with the brain regions that control mood, motivation and fear.
Once a perceived threat has passed, hormone levels and all systems return to normal. 
This served us greatly when most threats were actually life threatening—think back to hunter/gatherer times. 
Unfortunately, our bodies’ systems can’t differentiate between life threatening and non-life threatening stressors. So, when someone cuts us off in traffic, when we have an important job review coming up, when we know we’ll have to talk to that family member that always triggers us, our bodies are still sent into this fight or flight mode even though our lives are not in danger.
And when these stressors are always present and you constantly feel under attack, that fight-or-flight reaction stays turned on and cortisol remains chronically high. (Source)

How to Recognize High Cortisol Levels

Cushing’s Syndrome

High cortisol can be caused by chronic stress, overactive pituitary glands, high circulating estrogen, or medication side effects—most commonly birth control or steroids. It sometimes is diagnosed as Cushing’s syndrome.

Cushing’s Disease

If the cause is determined to be primary adrenal disease or a tumor on the adrenal glands, rather than chronic stress or medication, it may be diagnosed as Cushing’s Disease. This is much rarer and more serious. (Source

Symptoms of High Cortisol:

  • high blood pressure
  • a flushed face
  • muscle weakness
  • increased thirst
  • urinating more frequently
  • changes in mood, such as feeling irritable or low
  • rapid weight gain in the face and abdomen
  • osteoporosis
  • bruises or purple stretch marks appearing on the skin
  • decreased sex drive
  • irregular periods
  • high blood pressure
  • type 2 diabetes
  • fatigue
  • impaired brain function
  • infections

Long-term high cortisol levels can increase your risk of various health issues since cortisol affects so many aspects of the body, from heart disease and obesity to anxiety and depression.

Understanding Low Cortisol Levels

If cortisol levels become too low, it can cause issues for you as well. There are two primary causes of low cortisol: Addison’s disease (or primary adrenal insufficiency) and secondary adrenal insufficiency.

Addison’s disease 

Addison’s disease is an autoimmune condition because it is a result of the body attacking itself causing physical damage to the adrenal glands themselves. “For unknown reasons, your immune system views the adrenal cortex as foreign, something to attack and destroy.” (Source)
Like Cushing’s disease, it is more rare.

Secondary adrenal insufficiency 

This happens when the adrenals aren’t stimulated properly to produce cortisol. This is caused when a pituitary gland (a pea-sized gland at the base of the brain) fails to produce enough adrenocorticotropin (ACTH) hormone, whose job it is to stimulate the adrenals. (Source)
This is NOT caused by damage or illness of the adrenals, but rather autoimmune responses and stress-related illness. For example, women with chronic fatigue syndrome are more likely to have reduced cortisol levels. 
This study suggests that low activity levels, depression and early-life stress appear to reduce cortisol levels and by causing hypothalamic–pituitary–adrenal (HPA) axis (a complex set of interactions between two parts of the brain—the hypothalamus and the pituitary glands—and the adrenal) dysfunction. 

Acute Adrenal Insufficiency Crisis

Very rarely, something called acute adrenal insufficiency crisis can become a life-threatening condition. It occurs when there is a sudden interruption of adrenal or pituitary gland or sudden interruption of adrenal replacement therapy.
Symptoms of adrenal crisis are lightheadedness or dizziness, weakness, sweating, abdominal pain, nausea and vomiting, or even loss of consciousness. Risk factors for adrenal crisis include physical stress such as infection, dehydration, trauma, or surgery, adrenal gland or pituitary gland injury, and ending treatment with steroids such as prednisone or hydrocortisone too early. (Source)

Symptoms of Low Cortisol:

  • fatigue
  • dizziness
  • muscle weakness
  • gradual weight loss
  • changes in mood
  • areas of the skin turning darker
  • low blood pressure


Testing Cortisol Levels

Blood tests are the most common way of measuring cortisol, but it can also be measured using saliva or urine. (Source)
Since cortisol levels change throughout the day as we mentioned above, the range for “normal” will be different depending on what time it is. 
The standard for a cortisol blood test is to test once in the morning when cortisol levels are at their highest, and again in the afternoon after levels have declined.
Test results are affected by a number of things, so pinning down a “normal” is more than strictly looking at one set of numbers. Your health practitioner should take into account your age, gender, health history, test method, test timing, and other lifestyle influences.
According to University of Rochester Medical Center, for most tests, normal ranges are:

  • 6 to 8 a.m.: 10 to 20 micrograms per deciliter (mcg/dL)
  • Around 4 p.m.: 3 to 10 mcg/dL

If you have noticed any of the symptoms mentioned above, or something feels “off,” I want to encourage you to reach out to myself or another functional health practitioner and begin exploring the cause.
In a later blog, we’ll talk about natural ways to manage cortisol levels so you can feel like yourself again!