Thyroid Tests - Why Doctors Miss Issues And What to Test

Added: 2026-05-25

[00:00:00]Why do lab tests often miss thyroid issues? Thyroid problems are often missed because most doctors only check TSH. That's just the hormone that goes from your brain to your thyroid. Your thyroid then produces what's called T4.

[00:00:13]T4 is your inactive thyroid hormone. It needs to be converted to its active form called T3. T3 then needs to be uptaken by the tissues. So, when you're just measuring TSH, you're missing what the body's actually producing, if it's being converted effectively, and is that system actually utilizing that thyroid hormone. That's why it's really important that when you're measuring thyroid, you're measuring things like TSH, total and free T4, total and free T3, T3 uptake, reverse T3, and both antibodies to ensure that there isn't an autoimmune component to this issue as well.