Cortisol is commonly called “the stress hormone” due to its role in the body’s response to perceived threats or increased emotional demands. In this post, we outline how the hormone is measured and what the results might indicate.
What is cortisol?
Cortisol is made by the adrenal glands. It is implicated in the stress response, as levels increase when the pituitary gland releases another hormone, called adrenocorticotropic hormone (ACTH).
Cortisol has many functions. It helps the body use sugar (glucose) and fat for energy (metabolism), as well as manage stress.
A person’s cortisol levels can be affected by many conditions, such as
- physical stress
- emotional stress
- strenuous activity
- infection
- injury
Measuring cortisol
A cortisol test measures the hormone's level in the blood, which may indicate problems with the adrenal or pituitary glands.
Normally, cortisol levels rise during the early morning hours and are highest at about 7 a.m. They drop very low in the evening and during the early sleep phase. But this pattern may be reversed if a person sleeps during the day and are up at night. If the individual doesn’t have this daily change (diurnal rhythm) in cortisol levels, they may have overactive adrenal glands, a condition called Cushing's syndrome.
The timing of the cortisol test is very important because of how cortisol levels vary throughout the day. If the patient’s doctor thinks they might make too much cortisol, the test will probably be done late in the day. If the doctor thinks they may not be making enough, a test is usually done in the morning.
Cortisol level test results
Once a patient has their results, it’s important that they review them with their medical provider. They can help explain what it might mean if the level is in the “normal,” “low” or “high” range.
Normal value
Each lab has a different range for what's normal. The lab report should show the range that the patient’s lab uses for each test. The normal range is just a guide; the patient’s doctor will look at the results based on the individual’s age, health and other factors. A value that isn't in the normal range may still be normal for that person.
High value
A high level of cortisol in the blood can be an indicator of:
- Cushing's syndrome, a disorder that can be caused by overactive adrenal glands, an adrenal gland tumor, some types of cancer or long-term use of corticosteroids.
- Severe liver or kidney disease, depression, hyperthyroidism or obesity.
- Pregnancy or birth control pills
- Recent surgery, illness, injury or whole-body infection (sepsis).
Low value
A low level of cortisol in the blood can be caused by:
- Problems that affect the adrenal glands directly, such as Addison's disease or a tuberculosis infection of the adrenal glands.
- Problems with the pituitary gland that affect the adrenal glands, such as cancer or a head injury.
It’s a good idea to check cortisol levels if you have concerns about your health, but also as part of your annual exam. If you need help scheduling an appointment or establishing care with a provider, our Access Center can help. Call any time, at 877-PPG-TODAY or 877-774-8632 for assistance.
Copyrighted material adapted with permission from Healthwise, Incorporated. This information does not replace the advice of a doctor.
