Conversion

[Hypomom]

Hi.

How does one know if they have a t4 to t3 conversion problem????

[Saggyuk]

The only way would be to have a T3 blood test to see if low

Most GPS are unable to test for this or wont so for many, private testing is the only option but it's not hugely expensive. If you don't have an endo that will do the test, you can look at the private test section of thyroiduk.org.uk

Apologies, I would have linked it but am unable to for some reason

[humanbean in reply to Saggyuk]

Anyone doing a Free T3 test to identify any conversion problems needs to be aware it has to be done at the same time as a Free T4 test. Doing them separately doesn't tell people anything useful.

[Saggyuk in reply to humanbean]

Apologies, yes, sometimes I don''t think about how it will be read by someone else lol. I have always done mine with tsh and t4 so didn't think of it any other way

[Heloise]

There are links in this article that may help. Also a reverse T3 test is recommended by some authorities. stopthethyroidmadness.com/2...

[gizmomonster]

Blood Test to see if FT3 is low, also see if you carry recessive for the DIO2 gene, where you genetically don't convert. You'd need a genetic test for that.

[dang]

Get FT3 and FT4 tested together. Take the FT4 result divide by FT3 to find your ratio. If ratio higher than 4:1 you have a conversion issue. Normal conversion happens from 3:1 to 4:1. People with bad conversion end up with much higher ratio (I ended up over 7:1).

[LAHs in reply to dang]

Good answer dang. I would like to point out that you have to have the units the same. In the US we get FT3 in pg/mL and FT4 in ng/dL. You can get round this in 2 ways. Either Google a converter of pg/mL to ng/dL or use each at the units they are measured in, do what dang says but multiply your answer by 10.

Perhaps in the UK these are measured in the same units, in this case you have no prob, just do as dang says.

[dang in reply to LAHs]

Yes of course. You'd have to move the decimal point over in that case. Correct you are! They should be the same unit of measurement 🙂 I'm from Germany and some labs give results in mixed units here too yet I forgot to mention it, thanks for catching that!

[Katepots]

Also if you are on a decent amount of T4 and you still feel like you're dragging yourself around every day, plus gaining weight and cholesterol rising, there's a huge chance you're not converting T4 adequately.

If this is the case and Dr won't test FT3 There is private testing.

Sometimes if your RT3 is high a cause is high cortisol as blocks the conversion of T4 to T3 favouring conversion to T3 and putting you in a more hypo state.

[Newday64]

I think how you are feeling is a big indicator. When I was taking levo I had heart palpitations, extreme anxiety, painful neck & joints, hair loss, fainting & zero energy. I ended up in hospital where an endo told me my blood tests were 'perfect'. He reluctantly allowed me to go t3 only & I am now able to live a fairly normal life. So did I have a problem converting - I think I must, despite blood test,results.

T3 was my last resort after taking iron, vitamins, b12 injections, going gluten free - I tried really hard to improve my T4 conversion, but nothing worked. T3 is not the answer to everything, but I think it saved my life!

[TSH110]

Levothyroxine does not resolve symptoms at any dose but NDT does?

[Clutter]

Hypomom,

Low TSH with high (in range) FT4 and low FT3 indicates poor conversion.

[dang in reply to Clutter]

What if TSH is low, FT3 is low but FT4 is over range? Does that not also indicate poor conversion? Just asking because that's what happened to me.

[Clutter in reply to dang]

Dang,

Yes, that also indicates poor conversion.