04/09/2026
Most women are taught that TSH is the “thyroid test.”
But the truth is that TSH does not measure thyroid function. It measures brain perception.
TSH is produced by the pituitary, and it reflects how the brain is sensing thyroid hormone levels. It does not tell us how the thyroid gland is performing. It does not tell us how well your tissues are converting T4 into active T3. And it does not tell us what your immune system is doing behind the scenes.
TSH also cannot show us:
• whether your cells are actually using thyroid hormone
• whether Hashimoto’s is active long before TSH changes
• whether stress physiology is suppressing conversion
• whether reverse T3 is blocking thyroid hormone at the receptor level
This is why so many women hear “your thyroid is normal” while feeling anything but normal.
TSH is one piece of the puzzle. It is not the whole picture.
And you deserve the whole picture.