From the thyroid disorders ebook of chris kresser:
What do you guys think about this ?
One little known role of the gut bacteria is to assist in converting inactive T4 into the
active form of thyroid hormone, T3. About 20 percent of T4 is converted to T3 in the GI
tract, in the forms of T3 sulfate (T3S) and triidothyroacetic acid (T3AC). The conversion of
T3S and T3AC into active T3 requires an enzyme called intestinal sulfatase.
Where does intestinal sulfatase come from? You guessed it: healthy gut bacteria.
Intestinal dysbiosis, an imbalance between pathogenic and beneficial bacteria in the gut,
significantly reduces the conversion of T3S and T3AC to T3. This is one reason why
people with poor gut function may have thyroid symptoms but normal lab results.
Inflammation in the gut also reduces T3 by raising cortisol. Cortisol decreases active T3
levels while increasing levels of inactive T3.
What do you guys think about this ?