What is Reverse T3 (rT3)? And why should rT3 testing be a part of a functional medicine approach to assessing thyroid function?
Reverse T3 (rT3) is a form of thyroid hormone produced by the body, but unlike T3, it is considered inactive and doesn't play a significant role in regulating metabolism. At Tendwell, we consider the measurement of reverse T3 levels to be an important aspect of comprehensive thyroid testing, which is, in turn, an important component in many holistic health plans. In some cases, an elevated rT3 level can be an indication of a problem with the conversion of the inactive form of thyroid hormone (T4) to the active form (T3). This is important because T3 is the hormone that has the most metabolic activity and is responsible for regulating many body functions such as heart rate, body temperature, and energy levels.
In situations where rT3 levels are high, it may be an indication that the body is producing more rT3 instead of the active T3, which can lead to hypothyroid-like symptoms even though TSH (thyroid-stimulating hormone) and T4 levels may appear normal. Your functional medicine doctor or practitioner at Tendwell can help you determine the cause and find the best treatment.
Reverse T3 levels may also be impacted by factors such as illness, stress, and medication use, which can cause the body to produce more rT3 and less active T3.
The functional medicine approach looks for potential root causes. We measure rT3 levels, which can provide a more comprehensive picture of thyroid function and help identify potential issues with thyroid hormone conversion that may not be detected by other thyroid tests. However, it's important to interpret rT3 levels in conjunction with other thyroid hormone measurements and clinical symptoms to make an accurate diagnosis and guide treatment decisions.
The treatment of high reverse T3 (rT3) levels will depend on the underlying cause of the elevated levels. If the high rT3 levels are due to an underlying illness, such as a severe infection or chronic inflammation, then treating the underlying condition may help to normalize rT3 levels. If the high rT3 levels are due to stress, reducing stress levels through relaxation techniques, exercise, or other stress management strategies may be beneficial. If the high rT3 levels are due to medications that interfere with thyroid hormone conversion, switching to a different medication or adjusting the dosage may be necessary. Additionally, ensuring optimal levels of key nutrients, such as selenium, zinc, and iodine, which are important for thyroid hormone production and conversion, may also be beneficial.
In some cases, a medication called T3 (triiodothyronine) may be prescribed to help increase active thyroid hormone levels and reduce rT3 levels. However, this approach should only be used under the guidance of a functional medicine doctor who can monitor thyroid hormone levels and adjust the medication dosage as needed.
It's important to note that addressing high rT3 levels requires a comprehensive approach that takes into account the individual's medical history, symptoms, and other factors that may be contributing to thyroid hormone imbalances. Therefore, it's important to work with a functional medicine doctor or functional medicine nurse practitioner who is knowledgeable about thyroid function and can provide personalized treatment recommendations.
