TSH
Also known as Thyroid Stimulating Hormone
What it is
Thyroid-stimulating hormone is produced by the pituitary gland to tell your thyroid how much thyroid hormone to make. It moves inversely to thyroid hormone output: TSH rises when the thyroid is underactive and falls when it's overactive.
Why it matters
TSH is the standard first-line marker for thyroid function because it typically shifts before thyroid hormone levels themselves move outside a normal range, making it more sensitive to early over- or under-activity. It's a foundational marker precisely because thyroid function touches nearly every metabolic process in the body, from energy and weight regulation to heart rate and mood, and a subtle drift in either direction is often felt as fatigue or brain fog well before it shows up on paper. When TSH is out of range, the extended thyroid markers in Signal and Source, including Free T3, Free T4, and thyroid antibodies, are what help explain why.
TSH is one of the markers in Zaro's Surface panel and every tier above it.
This information is for educational purposes and is not a substitute for professional medical advice. Always talk to a physician about your specific results and health history.
← All biomarkers