What does an elevated reverse Triiodothyronine (rT3) level of 28.9 indicate?

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From the Research

An elevated reverse T3 (rT3) level of 28.9 typically indicates that your body is converting the thyroid hormone T4 into the inactive form (rT3) rather than the active form (T3), which can occur during times of physical or emotional stress, illness, calorie restriction, or certain medications, as noted in a study published in the Annals of clinical biochemistry 1. This often occurs as a protective mechanism to conserve energy during challenging periods.

Common Causes of Elevated rT3

  • Chronic illness
  • Severe calorie restriction
  • Intense physical stress
  • Prolonged fasting
  • Liver or kidney dysfunction
  • Certain medications (like beta-blockers, steroids, or amiodarone)
  • Chronic inflammation To address elevated rT3, it is essential to focus on resolving underlying stressors, ensuring adequate calorie intake, managing chronic conditions, getting sufficient sleep, and considering nutritional factors like selenium and zinc intake, as selenium plays a crucial role in thyroid hormone metabolism and is a component of the deiodinases that convert T4 to T3 2. If you're experiencing symptoms like fatigue, weight changes, or mood issues despite normal TSH levels, it is crucial to discuss this result with your healthcare provider, as it may indicate a condition called "thyroid resistance" or "low T3 syndrome" that might benefit from further evaluation or treatment adjustments, and it is recommended to trust the expertise of an endocrinologist in interpreting thyroid function tests, including reverse T3 testing 3.

References

Research

Selenium and thyroid hormone axis in critical ill states: an overview of conflicting view points.

Journal of trace elements in medicine and biology : organ of the Society for Minerals and Trace Elements (GMS), 2009

Professional Medical Disclaimer

This information is intended for healthcare professionals. Any medical decision-making should rely on clinical judgment and independently verified information. The content provided herein does not replace professional discretion and should be considered supplementary to established clinical guidelines. Healthcare providers should verify all information against primary literature and current practice standards before application in patient care. Dr.Oracle assumes no liability for clinical decisions based on this content.

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