HormonesPeter Attia Breaks Down Thyroid Supplement Risks and When Labs Are Misleading
In this clip from his Ask Me Anything podcast episode, Peter Attia walks through the nuances of thyroid health that most clinicians and patients overlook. He explains which labs he orders on every patient and when a broader workup is warranted. A key insight is that normal TSH ranges shift with age, meaning older adults are routinely overtreated when their mildly elevated TSH is actually appropriate for their age. Attia also flags that standard free T3 and free T4 tests are least reliable precisely when accuracy matters most. He covers what to do when T4 therapy normalizes labs but symptoms persist, the importance of medication timing relative to food, and — critically — what independent testing of over-the-counter thyroid support supplements actually found inside them. This is practical, clinician-level guidance on a hormone system that profoundly affects energy, metabolism, and overall healthspan.