I’ve had a lot of questions about thyroid testing lately.   So I decided it was time for a blog post to address these questions.  If your doctor orders a TSH (Thyroid Stimulating Hormone) test only and proclaims you fine, you need to consider the continuation of your relationship.  TSH is a pituitary hormone.  It measures how much hormone is being sent out to “stimulate” your thyroid into making more thyroid hormones.  This hormone tells you nothing about how well your thyroid is working to create the correct hormones.  So what should be tested and why?

Free T4:  This hormone is the basic thyroid hormone.  It is not an active hormone but the hormone that will be converted to the active metabolic hormone Free T3 in the liver and kidneys.  Why do I recommend Free T4 vs T4?  Because the free form is the one that is unbound and available for the body to use.  When optimum, most people feel best mid range.  This would be an approximate value of 1.4.

Free T3:  This is the active metabolic hormone.  You will find the majority of the issues with sub-clinical hypothyroidism is with this value.  This hormone is what gives you energy, keeps you slim, helps with brain fog, joint pain and many more important functions.  The optimum value for most people is the upper 1/3 of the range.  This is approximately 3.5 – 4.5 for most lab ranges.

RT3 (Reverse T3):  In some cases the body creates something called reverse T3.  The effect this has is to negate the FT3 that the body is creating.  If you have an optimum FT3 but a high RT3 and still have hypothyroid issues this may be your problem.  My Iodine Group members have had success in lowering RT3 through lowering their cortisol levels (adrenal fatigue) and cleansing their liver.  Taking synthetic T3 has proven to be a temporary fix.

TPO Ab (Thyroperoxidase Antibodies):  This is an antibody that works against the TPO enzyme that is used to convert iodide to iodine  to add to tyrosine on thyroglobulin for production of thyroixin (T4) and triiodothyroinine (T3) in the thyroid colloid.

Tg Ab (Thyroglobulin Antibodies):  This is an antibody that works against the protein thyroglobulin that is a critical component of the thyroid hormone creation process.

The bare minimum tests are the TSH, FT3 and FT4.  If these still don’t give you answers then adding the RT3 and antibodies will rule out any potential issues that may be missed.

Recommended reading:
Hypothyroidism Type II   by Dr Mark Starr
Hypothyroidism The Unsuspected Illness by Dr Broda Barnes (this may be difficult to find)
Overcoming Thyroid Disorders by Dr David Brownstein

Feeling hypo and being told that you are “in the range” and are fine, is a frustrating place to be.  I know…it took me 7 doctors before I found one that would help me based on not only my labs but how I was feeling.  These doctors are worth their weight in gold and can be difficult to find.  Joining local thyroid groups on Facebook or other social media sites can help you to find others that will give you a recommendation for a good doctor.  You may have to travel a distance to see one.  I have to travel 150 miles to my doctor.  But he gave me my life back and that is worth it!