TPO Antibodies
Also known as Thyroid Peroxidase Antibodies
What it is
Thyroid Peroxidase antibodies are produced when the immune system mistakenly targets an enzyme the thyroid uses to produce hormone, and their presence is a marker of autoimmune thyroid activity.
Why it matters
TPO antibodies are the primary marker used to identify Hashimoto's thyroiditis, the most common cause of hypothyroidism, and autoimmune activity against the thyroid can be measurable in these antibodies long before it's measurable in thyroid hormone levels themselves. That timing matters: someone can have normal TSH and thyroid hormone levels today while TPO antibodies signal that autoimmune thyroid disease is already underway and may affect thyroid function later. It's read alongside TSH, Free T3, and Free T4 to build a complete picture of thyroid health.
TPO Antibodies is one of the markers in Zaro's Source 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.
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