>Saliva Cortisol Test
Saliva versus blood cortisol
Medical doctors don't often test cortisol, and when they do, an 8 AM blood cortisol test is typically run. This test is fine to screen for rare endocrine conditions such as Addison's or Cushings disease. However for most people who simply feel tired or have "chronic fatigue syndrome" this test is mostly worthless.
1. Blood is not where you really want to look for cortisol
Blood tests how much hormone is in the blood. However, this is not a true representation of how much active hormone is effecting cells (which is what's most clinically relevant). In fact most hormone in blood are bound to proteins and thus inactive.
Saliva on the other hand is produced when cells in saliva glands spill out their contents. Therefore salvia represents true cellular levels of hormones and is therefore more clinically relevant than cortisol.
2. Saliva allow for multiple samples
Cortisol is normally 10 times higher in the morning than at night. However, in adrenal dysfuntion (either too low or too high cortisol) there is also a change in this basic pattern of cortisol release. As covered in the charts below, there is simply no way to accurately guess cortisol levels at 8PM based on a single 8AM sample.
Therefore, multiple cortisol samples are needed throughout the day. If testing blood, this would require multiple blood draws during the same day, which is just simply not practical.
3. No venipuncture required
Waking up extra early in the morning, to run to a lab and get stuck with a needle is a big stress in itself and make alter level of the body's main stress hormone, cortisol. Therefore, this is testing cortisol levels when a patient is under and unusual level of stress in the morning, not during a typical day.
Saliva tests require people to merely spit in a tube. This is a much less stressful test than getting a blood draw, and so getting the test itself will not change cortisol levels.
The saliva cortisol test
Saliva cortisol is usually measured 4 times during the day: upon waking up, noon, the late afternoon and before bed. Saliva is collected by spiting into a small collection tube, therefore it can be collected just about any time or any place. This is often referred to as an ASI or Adrenal Stress Index test.
The following examples show why cortisol needs to be measured throughout the day and the usefulness of this information.
Reference range is highlighted in green. Either too high, or too low cortisol is not a good thing.
Low cortisol, adrenal fatigue results
In this case cortisol is low through the entire day. Simply taking some herbs like ginseng and B vitamins (common advice for adrenal fatigue) would not nearly be enough support for someone in this situation.
Supplements would have be taken in appropriately high doses and may even include pregnenolone or DHEA (in small amounts) as hormonal precursors.
In addition and comprehensive health history would need to be reviewed, as this sort of adrenal fatigue doesn't just happen for no reason. Major stresses (psychological or from other illnesses) need to be dealt with in order to relieve some of the stress on the adrenal glands.
High and low cortisol, cortisol deregulation
Morning cortisol was so high it was literally off the chart. For the rest of the day if followed at the very bottom of reference range.
Such high AM cortisol indicates how the stress response may be causing insomnia (such as waking up 3 or 4AM every night)
This person may respond better to supplements that help the brain better regulate cortisol production (which is controlled by the hypothalamus and pituitary glands) than taking boat loads of adrenal supplements for daytime fatigue.
More patterns of cortisol deregulation
In these two cases rising cortisol during the end of the day (when cortisol should be decreasing) shows cortisol contributing to inability to fall asleep.
On the left morning fatigue related to low cortisol can be seen. The increase in cortsol was related to blood sugar imbalance (besides energy production, cortisol works very closely with insulin to regulate blood sugar), so nutritional support for both the adrenals and blood sugar was needed.
The test on the right has a large drop between 8AM and Noon, which indicates stress coming from the gastrointestinal system (since verified on other tests not covered in this page) which must also be treated.
Take away points
Each of the above cases had normal standard blood tests from conventional doctor.
Although fatigue is a common symptom, the exact pattern of cortisol can not easily be guessed.
The cortisol test is clinically significant (it can be used to help make health decisions).
- Saliva cortisol testing may be just as useful for certain cases of insomnia, and blood sugar disorders, as it is for fatigue.
- As important a hormone cortisol is, these tests are best interpreted in the context of the overall picture. Factors such as other illnesses, toxicity, nutrition, blood sugar, lifestyle and psychological stress must be considered as well. Cortisol testing is most beneficial when considered in relation to other factors.