Understanding Your Thyroid Test Results

Why the thyroid matters

Your thyroid is a small, butterfly-shaped gland in your neck that produces hormones controlling your metabolism, which is how your body uses energy. When it makes too little or too much hormone, you can feel it everywhere: energy, weight, mood, hair and even your heartbeat.

The numbers on your report

### TSH (Thyroid Stimulating Hormone) TSH is the single most useful thyroid marker. It is made by the pituitary gland to tell the thyroid how hard to work.

• **High TSH** usually means an **underactive thyroid** (hypothyroidism). The body is shouting at a gland that isn't responding.
• **Low TSH** usually means an **overactive thyroid** (hyperthyroidism).

A typical reference range is roughly **0.4–4.0 mIU/L**, but always read your own lab's printed range.

### T3 and T4 These are the actual thyroid hormones. **Free T4** and **Free T3** measure the active, unbound hormone available to your cells. They help confirm and grade what TSH is hinting at.

### Anti-TPO antibodies Anti-TPO checks whether your immune system is attacking your thyroid. A high level points to an **autoimmune cause** such as Hashimoto's thyroiditis, the most common reason for an underactive thyroid in India.

When should you test?

Consider a thyroid check if you have unexplained fatigue, weight change, hair thinning, feeling cold, irregular periods, or a family history of thyroid disease. It is also part of any good full-body health screen.

The bottom line

One out-of-range number is rarely the whole story. Thyroid results are interpreted together, alongside your symptoms. Use this article to understand your report, but let a doctor guide any treatment.

*This article is for general education and is not a substitute for professional medical advice.*