“if you have adequate t3 levels, will your body still convert t4 to t3?”
by thycarant
Yes. Your body will always convert T4 to T3. The only thing your body can do with T4 is convert it to T3.
T4 is the storage state of T3, to keep it simple.
- Comment
- Reblog
-
Subscribe
Subscribed
Already have a WordPress.com account? Log in now.
i hate thyroid cancer 
Actually T4 can get converted to RT3 (T7) instead and make you feel very hypothyroid.
LOL. Ok.
from labtestsonline.org :
3. What is reverse T3?
Reverse T3 (RT3 or REVT3) is a biologically inactive form of T3. Normally, when T4 is converted to T3 in the body, a certain percentage of the T3 is in the form of RT3. When the body is under stress, such as during a serious illness, thyroid hormone levels may be outside of normal ranges even though there is no thyroid disease present. RT3 may be elevated in non-thyroidal conditions, particularly the stress of illness. It is generally recommended that thyroid testing be avoided in hospitalized patients or deferred until after a person has recovered from an acute illness. Use of the RT3 test remains controversial and it is not widely requested.
Additionally:
2. What is FTI?
FTI stands for the Free Thyroxine Index and is also sometimes referred to as T7. It is a calculated value determined from the T3 uptake test and total T4 test and provides an estimate of the level of free T4 in the blood. It is rarely used now that there are methods available to measure free T4 and T3 directly.