From a holistic standpoint, chronic stress may be the culprit for many health problems. Whether a person is experiencing physical stress (athletic over-training, physical injury, etc.) or emotional stress (work stress, relationship troubles, worry over finances, etc.), the body is programmed to release stress signals such as cortisol and adrenaline (epinephrine) as part of the "fight or flight response." If cortisol levels are elevated, this indicates the adrenals are working very hard to keep up with the demand.
When circulating cortisol levels are high, it counteracts the action of insulin keeping glucose in the blood for a longer period of time. Cortisol elevation also down-regulates the immune system, creates sleep cycle disturbances, and has effects on hydration. Conversely, if ongoing stress has been a factor over a long period of time, cortisol levels may become depleted.
Low cortisol has been associated with low energy, poor motivation, recurrent infections, and gastrointestinal (GI) permeability problems. By measuring cortisol levels in saliva we are able to glean information on how well the body is coping with stress. Evaluation of DHEA provides additional insight into how long and to what degree the stress response has been activated.
Steroid hormone levels measured in saliva reflect the circulating level of free steroid rather than total levels and represent the bioavailable fraction available to the tissues. This is the hormone fraction that has already been delivered to salivary glands and then diffused passively into saliva. Therefore, measuring free hormone in the saliva is a better measure of the bioavailable fraction as compared to the protein-bound hormone in circulating blood, which “might” be delivered to the tissues. Salivary cortisol has now been well recognized as the “gold standard” for investigating adrenal function.