Thyroid Protocol: TSH, Free T4, Free T3 & Thyroid Antibodies

The thyroid gland, a butterfly-shaped organ at the base of your neck, functions as your body's metabolic thermostat. It produces hormones that regulate virtually every cell's energy production, influencing everything from heart rate and body temperature to cognitive function and weight management. What makes thyroid health particularly concerning for longevity is that subclinical dysfunction often goes undetected for years. In about 5-20% of adults aged 65 and older, TSH concentrations are elevated while circulating thyroid hormone levels remain within normal ranges. Research shows that Free T3 levels cannot be reliably predicted by TSH and Free T4 levels alone—direct measurement is vital for proper assessment. This means many people experience subtle thyroid imbalances that impact energy and metabolism without meeting criteria for full-blown thyroid disease.