There is a lot of emphasis on measuring thyroid function via a blood test. But just how accurate is a blood test? To measure thyroid function via a blood test, that is to assume that 100 percent or nearly 100 percent of thyroid hormone function takes place in the blood. Right? That is where it is measured.
In fact, there is nearly zero percent of thyroid function taking place in the blood. So what is the blood stream? It is a way to carry nutrients throughout the body and wastes back. Actually for thyroid function to occur, thyroid hormone has to leave the blood stream and penetrate each and every cell of the body, then penetrate into the nucleus and attach to a nuclear receptor. (Very few cells in the blood stream are nucleated).
Now we need some thyroid history. There are only three drugs from the 19th century still being used today: morphine, aspirin, and thyroid which was first used in 1891. For 80 years thyroid diagnosis was clinical: tired, constipated, dry skin, heavy menstrual cycle, foggy thinking, etc. Then in 1973, the present blood test came out and 80 years of clinical knowledge was thrown out. Previously the average dose was 3 to 4.5 grains of desiccated thyroid. Today rarely is this dose seen in the widespread population.
Back to the blood test. Is the blood test like buying a used car based on how much gas is in the gas tank? Does one need gas in the gas tank? Sure but without tires, motor, transmission, etc. a tank of gas does not do much good. Now it is readily evident for a car that just having a tank of gas is not enough, it is not an “end point measurement.” The endpoint measurement for a car is to drive it: can it start, get up to speed, stop? — all the things that make a car a car.
So what about a human and thyroid testing? Well, it is certain that the blood test is severely lacking in most respects (apart from autoimmune measurements) as it is not generally speaking an “end point measurement.”
In the human body, thyroid is akin to a thermostat. Broda Barnes M.D., whose medical focus was on the thyroid, measured oxygen consumption of 1,000 World War II servicemen at rest (an accurate measurement for thyroid function) and compared it to basal temperatures taken with oral, axillary (underarm), and rectal temperatures before getting out of bed in the morning. Dr. Barnes found that the easiest and most compliant was the axillary with a normal reading between 97.8 and 98.2. Of course, the best thermometers are the shakedown basal thermometers. This is not perfect a perfect test but it is closer to an “end point measurement” than just pulling blood.
As a secondary note, we at Dayspring Cancer Clinic almost never give any T4 thyroid product. Why? There has been a small observational study of unselected terminal patients with incurable solid tumors, whose extended survival was observed in a majority of patients using T3 after discontinuation of supplemental T4. Overall, 83 percent of subjects exceeded the expected (median) survival.
This is beyond the scope of this discussion but worthy of further investigation. Please see: TheOncologist 2015;20:1–5