Complete thyroid function assessment including T4,Free(Direct), TSH, Free Thyroxine Index, Thyroxine (T4), Triiodothyronine (T3), and T3 Uptake.
Thyroid hormones set your metabolic baseline, influencing energy production, body temperature, heart rate, mood, and how efficiently you burn fuel — so subtle shifts can show up as fatigue, unexplained weight changes, cold intolerance, or sluggish recovery. This panel pairs the comprehensive Thyroid Profile II (TSH, total T4, T3 Uptake, and the calculated Free Thyroxine Index) with directly measured Free T4 and Free T3, giving you both the pituitary signal (TSH) and the actual amount of active, unbound hormone your tissues can use. Measuring these together matters because TSH alone can look normal while free hormone levels tell a different story, and Free T3 reflects the biologically active form that drives metabolism. Reviewing the results with your clinician can help clarify whether symptoms have a thyroid-related component or whether your levels sit comfortably within range. Rather than ordering these markers piecemeal across multiple visits, a single blood draw captures the full picture at one point in time, which is more convenient and easier to interpret as a set. Results are best understood in context with your history and any symptoms — this is information to inform a conversation, not a diagnosis.
For athletes & active people
For athletes, thyroid function is tightly linked to energy availability, and prolonged heavy training combined with inadequate fueling can suppress thyroid hormone output, contributing to persistent fatigue, poor recovery, and stalled adaptation. Tracking Free T3 and Free T4 alongside TSH gives active people an objective window into whether their metabolic engine is keeping pace with their training load, which can be a useful data point when investigating unexplained performance plateaus or excessive tiredness.
Order online
Choose your lab and check out. We send your lab requisition automatically — no doctor visit needed.
Get your sample collected
Visit a lab service center near you for a quick blood draw (or book at-home phlebotomy where available).
See your results
Your results land in your Insider portal, ready to review and act on — that easy.
Insider panel price
$49.26$145
2.9× less than retail
Versus the typical direct-to-consumer retail cost of ordering these tests individually (illustrative — consumer prices vary by provider and region). Your $20 order fee is waived as an Insider.
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