Thyroid UK
89,121 members103,651 posts

Can anyone tell me if I am pooling T3?

Can someone work out my RT3 ratio to see if I am pooling please?

Just that the result I get on STTM calculator is over a million and surely that cannot be correct!

TOTAL T3 1.8 ug/L

RT3 0.11 ng/mL

5 Replies

I think it is broken.

NOTE: this is a BETA calculator. If something didn’t come out right, let my brainy techs and I know. Email Janie via the Contact Me below with your comments.



This is the ratio I get on that calculator


Surely cannot be right!?


My answer, using steam (lots!) and calculator, is that the TT3/RT3 ratio is 16.363. According to Dr Kent Holtorf P174-175 STTPM book, "If you only used a total T3 your ratio to the RT3 would be 10 or higher for healthy low levels of RT3."

Er, 1 nanogram equals 1000micrograms. so express 1.8 ng as mcg., 1.8 x 1000 = 1800mcg.

RT3 is already in micrograms, but is expressed as per millilitre, 1000th of a litre used for the TT3. Therefore, multiply the RT3, which is per millilitre, by 1000 to make it per litre (follow?? I am struggling!)

Anyway, my calculator says to divide TT3's 1800 micrograms by RT3's 110 micrograms.

1800 divided by 110 is 16.363636....higher than Dr Holtorf's "10" .

Is there a mathematician in the house? Am I right?



STTM book - don't know how that P snuck under the wire.


Sorry in a hurry, have you seen both of these?


You may also like...