Thyroid system

Thyroglobulin Antibodies (TgAb)

TgAb

Antibodies against thyroglobulin — a secondary marker for autoimmune thyroid disease.

What is it

Thyroglobulin Antibodies (TgAb) — in plain English.

Thyroglobulin antibodies target thyroglobulin, a protein involved in thyroid hormone storage. Elevated levels are another marker of autoimmune thyroid disease.

Why it's measured

What TgAb can reveal.

TgAb has been associated with autoimmune thyroid conditions and is often measured alongside TPO antibodies in research and clinical practice.

Reference range

Where most laboratories draw the standard line.

Standard laboratory reference

< 20 IU/mL

Reference ranges vary by laboratory. Your individual reference range will appear on your test report and should be interpreted by your physician in the context of your overall health profile.

What results may indicate

Higher vs. lower TgAb — at a high level.

Elevated

Has been associated with autoimmune thyroid disease in published research.

Lower

Is generally considered favorable.

These associations are general. They are not a personal diagnosis or prediction. Discuss your individual results with your physician in the context of your full health profile.

When it's measured

When TgAb is typically run.

Used alongside TPO antibodies in autoimmune thyroid evaluation.

Related markers

Often measured alongside TgAb.

Measured in

TgAb is one of 160 biomarkers in the Apex Panel.

A complete look at your heart, hormones, metabolism, inflammation, and longevity systems — drawn at Quest or LabCorp, reviewed by a U.S.-licensed physician.

Explore the Apex Panel
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This information is for general educational purposes only and is not medical advice. Lab results alone are not intended to diagnose, treat, or cure any condition and do not replace the advice of a healthcare provider. OPTML does not offer medical advice, a diagnosis, medical treatment, or any form of medical opinion.