Definition
What TSH measures
Thyroid-stimulating hormone is released by the pituitary to tell the thyroid how much hormone to make. It is a control signal, not the thyroid hormone itself.
Illustrative sample band · Synthetic
2.1mIU/L
0.1Sample target 0.5–2.5 mIU/L4.3
Why it matters
How clinicians usually read it
It is the entry thyroid marker. Free T4, Free T3, and antibodies complete the picture when symptoms and TSH disagree.
When it reads low
A lower value can mean
A low TSH can mean the thyroid is over-producing hormone, that replacement is high, or that the pituitary signal is suppressed. Symptoms and Free T4 belong in the same read.
When it reads high
A higher value can mean
A high TSH often means the thyroid is under-producing and the pituitary is pushing harder. Biotin, timing, and illness can also move the number.
Questions for a clinician
Bring the number into a real conversation
01
Should Free T4, Free T3, or TPO antibodies be read with this TSH?
02
Could biotin, timing, or a recent illness have shifted it?
03
How do my energy, temperature, and heart-rate symptoms line up with this?
Educational boundary
Educational information only. Displayed ranges are illustrative sample bands, not a diagnosis, treatment plan, or substitute for the contracted laboratory report and a qualified clinician.
See it as a sample result
The sample dashboard shows an illustrative reading, target band, and trend for TSH.