THYROID

The thyroid gland is located in the front of the neck, just below the larynx (Adam’s apple) and is composed of two lobes.  It weighs between 15 and 20 grams (less than one once).  It has a blood flow of around five times the weight of the gland each minute.  The thyroid secretes two important hormones (triiodothyronine T3 and thyroxine T4) that play a major role in controlling the body’s metabolic function.  The secretion of T3 & T4 is mainly controlled by the release of thyroid stimulating hormone (TSH aka: thyrotropin), which is excreted by the anterior pituitary gland.  When the levels of T3 & T4 drop low, the pituitary gland releases more TSH in an attempt to cause the thyroid to make more T3 & T4.

T3 & T4 get released and they go via the bloodstream to help control metabolism, increase the number and activity of mitochondria (energy increase), increases active transport of ions through cell membranes (Na, K-ATPase: sodium potassium pump), carbohydrate and fat metabolism, growth, sleep, effects most other endocrine glands, sexual function, conversion of oxygen and calories into energy, and several other functions. 

The normal thyroid gland secretes 93% T4 and 7% T3 (Guyton 10^th edition).  The majority of T4 gets metabolized peripherally into different forms of T3.  Part of this is done in the liver by an enzyme (5’ diodinase).  Therefore it is helpful to have a properly functional working liver.  In ideal conditions, 40% of the T4 is converted into T3, around 20% is converted in RT3 (Reverse / inactive T3), around 20% is converted to T3S (sulfate) and T3AC (triidothyroactetic acid).  T3S and T3AC are inactive until they make there way to the intestinal tract and get activated by the micro flora of the intestinal tract.  This is why one must have a healthy bacteria (micro flora) level in the colon.  Most people have a functional imbalance in the liver and colon, therefore do you see how you can have symptoms of a thyroid disorder, but have normal thyroid labs. 

Most people that present with functional thyroid imbalances do not have primary thyroid problems.  There is more to the equation, than just looking at a TSH level.  What about the following factors:  thyroid hormone synthesis, binding and peripheral conversion are influenced by progesterone, estrogen, testosterone, cortisol, fatty acid metabolism, inflammation, liver and gut dysfunction, sugar metabolism, etc.

What are some of the areas that the thyroid influences (listed here, but not gone into detail on how)?  Bone metabolism, gut function, gallbladder / liver, body compensation, insulin and glucose metabolism, cholesterol and lipid metabolism, neurotransmitter expression, estrogen, protein, cortisol metabolism, thermoregulation, hot flashes, anemia and much more.

Iodine is the main component of thyroid hormones and is crucial in their production. The thyroid cells are the only cells in the body that absorb iodine.  The cells take an amino acid called tyrosine and combine it with iodine to make the thyroid hormones.  An iodine deficiency can lead to the thyroid malfunctioning, when this happens the brain keeps telling the pituitary gland to keep releasing TSH.  If the iodine levels are not sufficient, one can start seeing clinical signs of hypothyroid problems even before it would show up on a conventional blood test. One must be very careful with the use of iodine supplementation if you have a positive thyroid antibody test (auto immune thyroid), because this will make the condition much worse.  I suggest running a TPO (thyroid perioxidase antibody test) anytime you see symptoms of both hyper and hypo thyroid symptoms.  If you are doing the iodine absorption test via the skin and the iodine is disappearing within hours, I would run the TPO test before doing iodine to make sure you do not make a problem worse.

There are seven thyroid patterns to consider when evaluating the thyroids performance, all which are obtained from a proper lab order.

o       Hypothyroidism

o       Hyperthyroidism

o       Secondary hypothyroidism to primary pituitary hypo function

o       Thyroid under conversion

o       Thyroid over conversion

o       Thyroid binding hormone elevations

o       Thyroid resistance

It is crucial to at least get the following test done for proper evaluation:  TSH, T3 uptake, T4, FTI (free thyroxine index), and consider a TPO for auto immune problems.  Most doctors only run a TSH, problem with this; you miss most of the thyroid patterns listed above and end up getting mistreated.

When addressing thyroid function, one must consider looking strongly at evaluating the adrenal glands with an ASI test.  Looking at this whole picture will allow for the proper treatment when trying to restore proper thyroid function.