I found out that T4 is converted to the active form T3 in the liver. If you have insulin resistance or liver congestion, the conversion can be impaired.
This is true. Also, if one has leaky gut, it is also bad. It is good for liver to take bitters before meals. I am taking angostura bitters before meal, if remember.
For successful conversion iron, selenium are necessary. When Sherpa mention the T3 capsules, i realized that selenium was missing in my supps.