Cortisol is a steroid hormone that’s produced by the adrenal glands. It’s the primary hormone involved in stress and the “fight-or-flight” response our brains naturally have to perceived threats or danger—when you experience a stressor, a hormone in your brain triggers the adrenal glands to release cortisone and adrenaline. During this release, cortisol suppresses other functions.
Cortisol also has the following functions:
- Helps the body use sugar and fat for energy
- Helps the body manage stress
- Helps with immune function and the nervous system
- Plays a role in the circulatory and skeletal systems
Your cortisol levels may indicate issues with the adrenal or pituitary glands, such as producing too much or too little of important hormones.
Cortisol Levels and Testing
Testing is done to determine if cortisol levels are too high or too low in the adrenal glands. The timing of the test can be very important—cortisol levels vary during the day, rising during the early morning and peaking around 7 am.
Preparation for a Cortisol Test
You may be asked to prepare in some of the following ways:
- Avoiding strenuous activity the day before
- Lie down and relax for 30 minutes before the test
- Tell your doctor about all medications you’re taking
- Tell your doctor about any concerns you have, and fill out a medical test information form
Result ranges vary, but they may mean some of the following:
- High levels: High levels of cortisol may signal Cushing’s syndrome, a disorder caused by overactive adrenal glands. This might also mean liver disease, depression, hyperthyroidism or obesity. High levels can also be caused by pregnancy or birth control pills in some cases, or by things like recent surgery, illness, injury or whole-body infection.
- Low levels: Low levels of cortisol in the blood can be caused by conditions affecting the adrenal glands, such as Addison’s disease or tuberculosis in the adrenal glands. They can also relate to issues with the pituitary gland that affect the adrenal glands, including cancer or a head injury.
Results of a cortisol test can be affected by several factors, and in some cases these factors will make you unable to complete the test. Some of these factors include:
- Physical or emotional stress
- Pregnancy (can cause high urine cortisol levels)
- Low blood sugar
- Eating, drinking or exercising before the test
- Taking medications like birth control pills, estrogen or amphetamines
If you have abnormal levels of cortisol, your doctor will work with you to create a treatment plan.
“Cortisol in Blood.” WebMD. http://www.webmd.com/a-to-z-guides/cortisol-14668#1
“Cortisol Level Test.” Healthline. http://www.healthline.com/health/cortisol-urine#overview1