Diurnal Cortisol

The Diurnal Cortisol test measures the levels of the key stress hormone, cortisol, over one daily (ie:diurnal) cycle. Results, when compared with normal values, can serve to motivate individuals currently living under stress to learn new coping mechanisms and make positive lifestyle changes.


Collection can be done at home or at work. Samples are obtained four times in a day: In the morning (about 30 minutes after waking), noon, mid afternoon, and bedtime. Saliva measurement of cortisol is easy to do and, unlike blood and serum, where venipuncture may result in an anticipatory rise in cortisol, with saliva collection it does not.


About Cortisol


Cortisol can also be referred to as “the stress hormone.” Repeatedly high salivary cortisol levels throughout the day may indicate excessive glucocorticoid production, and an inability to adapt to continued stress.  Levels normally start high in the morning and decline as the day continues. They may fluctuate high or low at any of the four measurement times due to acute or chronic stress. Sustained high or low levels are often found in individuals with an imbalance in adrenal function.


The Importance of Balanced Cortisol Levels


Testing for free cortisol hormone in saliva is a non-invasive, simple way to map out the diurnal cortisol response and a convenient way of assessing adrenal gland function By measuring diurnal cortisol profiles in saliva, healthcare professionals may identify individuals whose stress adaptation is compromised and therefore at greater risk of developing chronic illness or conditions such as fibromyalgia, hypothyroidism, chronic fatigue syndrome and premature menopause.


Sample Diurnal Cortisol test report (optimized for Internet Explorer, Firefox and Safari)


Saliva Sample Collection - Frequently Asked Questions