Why do we do dried blood spot analysis to determine thyroid function? Accuracy! These days most doctors use standard blood work via venipuncture to evaluate the thyroid, usually only ordering TSH, not T3, T4 , reverse T3, or antibodies. Shame on them! TSH (Thyroid Stimulating Hormone) is a very fragile pituitary hormone in the liquid serum state. When drawn, it should be assessed immediately because of its fragility. The TSH is usually drawn first thing in the morning because it requires a 12 hour fasting. However, the serum may not be tested until afternoon, and the TSH will be degraded causing lower levels to be read. The other problem is that the levels for TSH are too broad, Most labs have normal values at .5 to 5.0. a thousand per cent variance! Doctors who have had extensive nutritional training, practice functional medicine, or who have had training such as I in aging and rejuvenative medicine, feel that levels over 2 are highly suggestive of hypothyroid. Based on these two discrepancies alone there are many patients that are hypothyroid that go undiagnosed. Approximately 2% of Americans, and for over 65 years of age, 10% of Americans are currently diagnosed with hypothyroidism. It is estimated by many doctors that there may be another 40-50% of Americans that are hypothyroid and have not been diagnosed. See section on website, WHAT DO WE TREAT? Hypothyroid.
Dried spot analysis captures the capillary hormone rich arterial blood, and then dries it, making the TSH more stable for analysis. In addition to TSH, T3, T4, reverse T3, and potential thyroid antibodies are evaluated. T4 must be converted to T3 to activate cell membrane receptor sites to be used in the body. If T4 and Reverse T3 are high, then the patient will be functionally hypothyroid. When the body is under stress it can convert T4 into Reverse T3. Reverse T3 is an inactive form, but it can occupy receptor sites, and therefore, deny access to the receptor sites for the bio-active T3.
I have had many patients with classic symptoms of low thyroid function such as dry skin, dry, brittle, thinning hair, chronic constipation, sensitive to cold, infertile, inability to lose weight despite diet and exercise change, chronic fatigue, or mental dullness have a standard blood test via venipuncture and TSH levels be within range. When these same patients used the died blood testing technology, abnormalities were present. In, addition basal body temperature readings under the arm, first thing in the morning, can give a fairly good assessment of determining if the thyroid rate is normal. More importantly, when sub-par function is detected, proper therapy could be initiated , giving the patient a better quality of life.
This service is provided through Hoffman Clinic for Optimal Health. Call today if you would like to schedule a test. 813-985-5190.
(c)Kelly Miller, DC NMD FASA FBAARM CFMP*, health coach for Hoffman Clinic for Optimal Health.
*Not currently licensed in Florida.