How do I know if my thyroid is really working?
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Often in my practice, my patients tell me "I feel my metabolism is slowing down, I feel sluggish, I'm exhausted and I'm always cold, I have checked my thyroid and it's fine". But it's really fine? Are the tests really accurate? What they are not telling us.
Let's try to do some clarity on this.
ASK FOR A FULL PANEL or THYROID COMPREHENSIVE BLOOD TEST
The Thyroid Comprehensive Blood Test Panel includes a Thyroid Profile with TSH, Tri-iodothyronine (T3) Free Serum, Thyroxine (T4) Free Direct Serum, Thyroid Peroxidase (TPO) Antibodies, Thyroid Antithyroglobulin Antibody (TAA) plus Reverse T3, Thyroxine-binding Globulin (TBG), Thyroid-stimulating Immunoglobulin (TSI), and Tri-iodothyronine (T3).
Doctors usually only prescribe TSH (thyroid-stimulating hormone).
TSH secretion is controlled by the hypothalamic hormone TRH (thyrotropin-releasing hormone) and the plasma level of thyroid hormones. If the TSH is between the levels, they usually do not prescribe further tests, but this is wrong. First, the TSH range is very wide, from 0.5 to 5.0 mUI / L, and secondly, other thyroid markers may be altered.
THE IMPORTANCE OF MEASURING free T4
Thyroxine or tetraiodothyronine - known more simply as T4 due to the molecular structure characterized by 4 iodine molecules - is the main thyroid hormone secreted by the follicular cells of the thyroid. Once released into the bloodstream, it is largely bound to the so-called TBG (Thyroid Binding Globulin), and to a lesser extent to albumin and transthyretin. Due to the low plasma concentration of thyroid hormones, TBG is usually present in excess of thyroid hormones available for binding.
To acquire biological activity and regulate metabolism in target cells, thyroxine must necessarily detach itself from this protein; for this reason, for some years it has been preferred to measure the plasma levels of the free fraction (free T4), rather than the absolute ones (total T4).
There are no unique normal values for the determination of T4. The reference ranges may differ in different laboratories, as they depend on many factors, such as the age and sex of the patient, the analytical methods, and the instrumentation in use.
For this reason, it is preferable to consult the ranges reported directly on the analysis report. It should also be remembered that the results should be evaluated as a whole by the physician who is familiar with the patient's medical history.
TSH can be in the range, or on the LOW SIDE, but free T4 CAN BE SLIGHTLY or very HIGH
A low TSH and high free T4 generally mean an overactive thyroid:
Hyperthyroidism (palpitation, anxiety, weight loss)
Toxic goiter
Basedow's ophthalmopathy
Inflammation of the thyroid gland (thyroiditis);
Early-stage Hashimoto's thyroiditis.
TSH can be in the range, or on the HIGH SIDE, but free T4 CAN BE SLIGHTLY or very LOW
A high TSH and low T4 mean an underactive thyroid.
Reduced values of free T4 are mainly due to:
Hypothyroidism
Endemic goiter
Advanced Hashimoto's thyroiditis.
TSH can be in the range but THE ANTIBODIES AGAINST THYROID CAN BE SLIGHTLY HIGH
Sometimes the TSH is in the range (perhaps towards the upper level), but the antibodies against the thyroid are slightly high.
This could be a sign of the onset of hypothyroidism or Hashimoto's disease. It is important to find out when it is just starting because it can be treated with a diet and by supporting adrenal health. I learned in school that you can't really heal your thyroid directly, because it's super sensitive, but you can work with the organs that are above and below.
You suspect that you have hypothyroidism or thyroid diseases run in your family. Why not book a 15-minute phone call for free to discuss your options.