It's estimated that as many as 25 million Americans have a thyroid problem, and half of them have no idea that they do. Hypothyroidism, or an under-active thyroid, accounts for 90% of all thyroid imbalances.
The thyroid, a butterfly-shaped gland in the center of your neck, is the master gland of metabolism. How well your thyroid is functioning is inter-related with every system in your body. If your thyroid is not running optimally, then neither are you.
Here are 10 signs that you could have an underactive thyroid:
How does you thyroid gland work?
Thyroid hormone production is regulated by a feedback loop between the hypothalamus, pituitary gland and the thyroid gland. Hypothalamic thyrotropin-releasing hormone (TRH) stimulates pituitary thyrotropin (TSH) synthesis and secretion.
In turn, TSH stimulates production and release of T4 and T3 from the thyroid gland. When enough T4 is produced, it signals to TRH and TSH that there is enough thyroid hormone in circulation and not to produce more.
About 85% of the hormone produced by our thyroid gland is T4, which is an inactive form of the hormone. After T4 is made, a small amount of it is converted into T3, which is the active form of thyroid hormone.
The role of Reverse T3 is not well known, however, I do see it elevated in persons under extreme stress...
To complicate matters, T3 also gets converted into either Free T3 (FT3) or Reverse T3 (RT3). It's the Free T3 that really matters in all of this, since it's the only hormone that can attach to a receptor and cause your metabolism to rise, keep you warm, keep your bowels moving, mind working, and other hormones in check. The role of Reverse T3 is not well known, however, I do see it elevated in persons under extreme stress and those who have mercury toxicity.
And finally, Hashimoto’s thyroiditis, an autoimmune disease, is the most common form of hypothyroidism and its numbers are rising annually. An autoimmune disease is one in which your body turns on itself and begins to attack a certain organ or tissue believing its foreign.
I routinely screen all of my patients for autoimmune thyroid disease by ordering Thyroid Peroxidase Antibodies (TPOAb) and Thyroglobulin Antibodies (TgAb).
Why is hypothyroidism so under diagnosed in the USA?
Many symptoms of thyroid imbalance are vague and most doctors spend only a few minutes talking with patients to sort out the cause of their complaint.
Most conventional doctors use only one or two tests
Most conventional doctors use only one or two tests (TSH and T4) to screen for problems. They are not checking FT3, RT3 or thyroid antibodies.
Most conventional doctors use the ‘normal’ lab reference range as their guide only. Rather than listening to their patients symptoms, they use ‘optimal’ lab values and temperature as their guide.
Which lab tests are best to determine if you have a thyroid problem?
I check the below panel on each of my patients. Make sure your doctor does the same for you.
- Free T4
- Free T3
- Reverse T3
- Thyroid Peroxidase Antibodies (TPOAb)
- Thyroglobulin Antibodies (TgAb)
What are the ‘optimal’ lab values for thyroid tests?
In my practice, I have found that the below are the ranges in which my patients (and myself) thrive. I listen to my patients as well and take how they are feeling into account.
- TSH 1-2 UIU/ML or lower (Armour or compounded T3 can artificially suppress TSH)
- FT4 >1.1 NG/DL
- FT3 > 3.2 PG/ML
- RT3 less than a 10:1 ratio RT3:FT3
- TPO –
- TgAb - < 4 IU/ML or negative