Why saliva tests may be better than blood
test to measure hormones

By Dr. Len Lopez

Blood tests have been considered the gold standard and the first test to be done when evaluating your health. The reliability of a blood test is immense and can provide some very critical information. Unfortunately, there are certain limitations when it comes to using blood tests to measuring hormones to see if stress is causing adrenal exhaustion or fatigue. Don’t get me wrong blood test can be used to accurately measure hormone levels, but those tests are more expensive and are not normally done on a routine blood test.

A typical blood test to measure hormones (cortisol and DHEA) will measure both the active and inactive form of any hormone. It is the active form of a specific hormone that tells us what is really going on and is the information you should be searching for. Typical blood tests tell you the total amount of both the active and inactive component of that hormone.

To measure the ‘active’ form of a specific hormone you need to do what is called a “free-fraction” measurement. It is a much more expensive measurement and is not typically done on a routine blood test. This is why people so often complain that the doctors couldn’t find anything wrong, but the patient knows something is NOT right.

Saliva tests are a much better way to measure hormones, not only because they are less expensive, but more importantly a saliva test only measures the ‘free-fractioned’ or the active component of the hormone.

There are a couple of other reasons to use a saliva test over a blood tests when evaluating Cortisol, DHEA and other related hormones. First, we are measuring how stress affects the body, many people feel an increased level of stress and anxiety by merely going to the doctor, which can create false positives and not give a true picture of your level of stress. A 24-hour saliva test is done in the privacy and convenience of your own home.

Secondly, Cortisol and DHEA fluctuate throughout the day. A blood test takes only a snapshot, while a 24-hour saliva test is more like a moving picture of how these hormones fluctuate throughout the body. A good test to measure adrenal function should consist of 4 measurements taken throughout the day. Maybe your hormones may be normal at one part of the day when you had your blood drawn, but it could fluctuate up or down, out of normal range, at other times of the day and could be the cause of your symptoms.

The over-or-under production of various hormones such as cortisol and DHEA, due to stress, can have a direct impact on the production of thyroid hormones, progesterone, estrogen, testosterone, FSH, LH and aldosterone, which regulates fluid balance. This is why it is so important to get accurate information, because the wrong information may take you down the wrong road of healing.

The Functional Adrenal Stress Index measures how stress is impacting your health and can help you determine if your adrenals are exhausted and fatigued.