There has been frequent questions recently on Reverse T3.
For information regardng Reverse T3 cursor down to No.4 to read the statement, which is in simple terms. An extract:-
Old studies show that on average, most people convert more than 50% of their T4 to reverse T3; correspondingly, they convert less than 50% of T4 to the metabolically active hormone T3. And the levels of reverse T3 fluctuate up and down through the day. Because of this, I’m never confident of coming to a conclusion that someone has a problem with high reverse T3, not unless the person has had multiple measures of the reverse T3 over a 24-hour period.
Like the TSH, free T4, free T3, reverse T3 levels vary dramatically every 30 minutes or so. Depending on when a person’s blood is drawn or saliva taken. Sometimes the levels will vary enough so that a clinician will give the patient a different diagnosis from the one that he or she would have given 30-minutes before or after the blood or saliva sample was taken.
So blood levels vary rapidly. Because of this, I don’t believe the reverse T3 or the other lab tests in general are very useful. However, I do believe the reverse T3 is useful under one circumstance: when we have enough measures to get averages over time, and when the levels are regularly way out of range. So, in my view, the reverse T3 can be useful, but I think its usefulness is limited, which is true of the TSH and other thyroid hormone levels. >>>