Thyroid tests 🧵 You can experience low thyroid symptoms even when blood tests are fine. TSH/T4 tests can detect problems with the thyroid gland, but they are BLIND to all downstream thyroid hormone issues. Even T3 tests are limited. What matters? T3 activating cells.
TSH is the most common thyroid test, and some consider it the gold standard marker of thyroid hormone activity; however, it does not directly test thyroid hormones, and therefore, it should not be relied upon. You can have low T3 in the blood or low cellular T3 activity, and
The thyroid gland produces two thyroid hormones. The first is T4, the storage form of thyroid hormone. Most of the thyroid hormone output from the gland is T4. The gland also produces some active thyroid hormone - T3. The benefits of T4 depend on how well it is converted into
T3 is THE thyroid hormone. It activates cell receptors, initiates gene expression, controls metabolism and growth, and influences temperature, heart rate, mood, cognition, fertility, and other physiological processes. ... but only when it reaches and activates the cell
A significant proportion of T4 is converted to reverse T3 (rT3) under normal circumstances. rT3 does not activate metabolism in the same way as T3 does. A higher ratio of rT3:T3 is a good marker of thyroid hormone conversion issues, both peripherally and, to a degree, within
Other reliable indicators of thyroid function have been used in the past, and they remain useful today for estimating thyroid hormone activity. The basal metabolic rate test (BMR) measures the energy your body uses at complete rest in a fasted, thermoneutral state, reflecting
The resting pulse is another indicator of thyroid function. Like all tests of thyroid activity, it is imperfect and unreliable on its own, but it becomes useful when combined with other tests, signs, and symptoms. T3 increases the resting pulse, and the resting pulse is
http://skool.com/thyroid if you need more help understanding/correcting hypothyroidism and low T3.
@lowmegatron I have hypothyroidism. The only time I didn't have symptoms was when I got my Levothyroxine from Valisure, which checked the medication to see if it was correctly formulated. If I get it from any other source such as Walgreens, CVS etc., I get all of the symptoms back.
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@lowmegatron My new doc just ordered T3 uptake test. Any insight on this test?