Updated February 11, 2022

Things that raise TSH:  (the terms “low”, and “increased” are relative to individual circumstances and must be interpreted accordingly)

• Too low T4 or T3 (free and/or total).
• Increased iodine intake.
• Dysfunctional hypothalmic signalling coming from:
  • brain (ans, emotion, sleep-wake),
  • other hormones,
  • biome,
  • skull infections.
• Simliar pituitary dysfunctions

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Things that lower TSH:  (the terms “high”, and “decreased” are relative to individual circumstances and must be interpreted accordingly)

• Too high T4 or T3 (free and/or total).
• Decreased iodine intake.
• Dysfunctional hypothalmic signalling coming from:
  • brain (ans, emotion, sleep-wake),
  • other hormones,
  • biome,
  • skull infections.
• Simliar pituitary dysfunctions

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COMBINATIONS OF FACTORS

Depending upon the combinations of the above factors, TSH can be an accurate or inaccurate measure of the body’s true need for thyroid hormones, such as for replacement.  Therefore, TSH can only be interpreted as a secondary value, not a primary one.

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INTERPRETING TSH LOW (depending upon lab, lower than approximately 0.5 mIU/L)

There are numerous cases when the T3 free and total are low, T4 free and total are low, and even Reverse T3 low, while the TSH is also low.  The most feasible explanation is that the pituitary gland is somehow not properly sensing or responding to these congruent stimuli.

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INTERPRETING TSH HIGH (depending upon lab, higher than approximately 1.5 mIU/L)

TSH can be high in the context of iodine repletion and therefore difficult to interpret.  However, iodine repletion doesn’t seem to greatly influence T4 and T3 production due to peripheral controls.  Therefore, the individual values of T4, T3 and RT3 can guide the need for more or less hormone.

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INTERPRETING RT3 HIGH

RT3 can be considered the “brake” of the system. This is pushed when T4 or T3 is high.  It is also raised by cortisol, and therefore can be a subjective measure of stress physiology. There are other factors that also influence RT3, such as bile acids which act as signal molecules (hormones) regarding the peripheral conversion of T4 to T3.

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INTERPRETING RT3 LOW