Dr. Linda has you have your sex hormones and your cortisol measured in saliva before prescribing hormone replacement. The laboratory that she has found that has the most accurate testing is Labrix. The following information is from their website: www.labrix.com
Why use saliva testing?
Appreciating the reliability of saliva testing is based on understanding the difference between steroid hormones in saliva and in serum. This difference is based on whether or not the hormones are bound to proteins in the medium used for testing. The majority of hormones exist in one of two forms: free (5%) or protein bound (95%). Only the free hormones are biologically active, or bio-available, and available for delivery to receptors in the body. Protein bound hormones do not fit the receptors and are considered non-bioavailable. When blood is filtered through the salivary glands, the bound hormone components are too large to pass through the cell membranes. Only the unbound hormones pass through and into the saliva. Saliva testing measures the bioavailable hormone - the clinically relevant portion delivered to the receptors in the tissues of the body.
Salivary hormone levels are expected to be much lower than serum levels, as only the unbound hormones are being measured. When healthcare providers measure serum hormone levels and prescribe hormone replacement therapy based on those results, patients are often overdosed. If the patients are then tested using saliva, the results are extraordinarily high and create confusion resulting from a lack of correlation between the two methods.
This discrepancy becomes especially important when monitoring topical, or transdermal, hormone therapy. Studies show that this method of delivery results in increased tissue hormone levels (thus measurable in saliva), but no parallel increase in serum levels. Therefore, serum testing cannot be used to monitor topical hormone therapy.
Saliva measures the "unbound" biologically active or free hormone levels in the body: When blood is filtered through the salivary glands, the bound hormone components are too large to pass through the cell membranes of the salivary glands. Only the unbound hormones pass through and into the saliva. What is measured in the saliva is considered the "free", or bioavailable hormone, that which will be delivered to the receptors in the tissues of the body.
Serum measures the "protein bound" biologically inactive hormone levels in the body: In order for steroid hormones to be detected in serum, they must be bound to circulating proteins. In this bound state, they are unable to fit into receptors in the body, and therefore will not be delivered to tissues. They are considered inactive, or non-bioavailable.
Only saliva testing measures topically dosed hormones: The discrepancy between free and protein bound hormones becomes especially important when monitoring topical, or transdermal, hormone therapy. Studies show that this method of delivery results in increased tissue hormone levels (thus measurable in saliva), but no parallel increase in serum levels. Therefore, serum testing cannot be used to monitor topical hormone therapy.
Who should be tested?
Both men and women experience changes in hormone levels with age. Sometimes those changes result in unpleasant symptoms that demand attention. Often, the changes are more subtle - yet there is still an impact on overall health. Hormone testing is applicable for:
Men and women concerned with changing hormone levels as a result of age.
Cycling women experiencing PMS symptoms, perhaps related to a hormonal imbalance.
Peri- and post-menopausal women concerned with their estradiol and progesterone levels for replacement considerations.
Those wishing to monitor their hormone levels following replacement therapy (oral, sublingual or topical), and subsequently regulate their supplement levels.
Anyone with symptoms involving fatigue, insomnia, stress, immunity problems, blood sugar problems, and an overweight body should be tested for cortisol levels as well as "sex" hormones.
Men and women of any age who are having symptoms of hormone imbalances should test for all hormones that may be associated with their symptoms. Men and women over the age of forty may want to do a baseline test. Frequently, imbalances will be detectable for a time period before symptoms gain attention.