- Primary hypothyroidism
- Hypothyroidism secondary to pituitary hypofunction
- Thyroid under-conversion
- Thyroid over-conversion, decreased thyroid-binding globulin (TBG)
- TBG elevation from contraceptives / hormone replacement therapy (HRT)
- Thyroid resistance
1. Primary Hypothyroidism
The thyroid gland gets lazy and the pituitary gland tries to “kick it in its pants” by pumping extra thyroid-stimulating hormone (high TSH). This is the only pattern of the six that may need HRT. (Hashimoto’s may need it, too.)
2. Hypothyroidism Secondary to Pituitary Hypofunction
The pituitary gets “lazy” (low TSH below 1.8) for many reasons:
- Chronic stress fatigues the gland
- Hormone pills, including Synthroid
- Creams with Estrogen
- Postpartum depression; pregnancy can fatigue the Pituitary Gland
- Fluctuating insulin/glucose levels (Adrenal Gland fatigue)
3. Thyroid Under-Conversion
The gland is making enough T4 but there is a decrease in conversion from T4 to the active form T3 (low T3). Why? Chronic Adrenal Stress gives rise to increased cortisol which suppresses T4 to T3 conversion. This is due to chronic infection / inflammation. This condition is often missed because low T3 doesn’t affect TSH – only T4 does – and T3 is rarely checked for with the blood test.
4. Thyroid Over-Conversion and Decreased TBG
Too much active T3 is made and is overwhelming the cells or too little TBG which means too much free T3. Why? The number one cause is insulin resistance, especially in women. The cells are not “listening” to insulin so more insulin is secreted. This increases testosterone levels in females resulting in too much free T3 and too little TBG.
5. TBG Elevation
Too much TBG in the blood and thus too little free T3. Why? Oral contraceptives or estrogen replacement therapy causes an increase in estrogen which leads to increases in TBG.
6. Thyroid Resistance
Pituitary and Thyroid glands are fine and so are the hormone levels. However, the hormones aren’t getting into the cells. Why? Chronic stress response stimulates the adrenal glands to produce too much cortisol which causes cells to be resistant to thyroid hormones.