conversion

[fiftyone]

If I need loads of levo to feel well (7 points above the range - doctors panic!!), but my T3 is normal, what does that say about the way I convert T4 to T3? Do I convert very slowly or very quickly??? Really puzzled about conversion. This pattern is normal for me.

[greygoose]

It's not a question of speed. It's a question of how well you convert. And if you need your FT4 well over-range to get a decent amount of T3, then you don't convert very well.

Conversion is when on atom of iodine is removed from T4 - four atoms of iodine per molecule - making it T3 - three atoms of iodine per molecule. This is done by the action of certain enzymes called deiodinase. But, not all of us can do that very well. There are many possible reasons why we can't do it very well - one being sub-optimal nutrients - especially selenium. So, it's a good idea to ask your doctor to test the basic nutrients: vit D, vit B12, folate, ferritin. Then, if they are sub-optimal, supplement them and see if it helps your conversion. Problem is, very few doctors know anything about conversion.

[fiftyone in reply to greygoose]

thanks for that.

[greygoose in reply to fiftyone]

You're welcome.

[tattybogle]

Speed is an interesting question . I don't think? we can know anything about the speed of conversion from blood levels. We can see how much , but not how fast.

I have T3 results on 108 / 111% T4 that gave 63 / 54% T3 ,

and ..................... from 66 / 85% T4 giving only 32 /36% T3 ,

so it seems i get more T3 when i have higher T4.

( I don't have any T3 results from when my T4 has been very over range, so don't know how much more i get then. but i currently have T4 16.6 [7.9-14] ie 142% and last year on the same dose it was 22.5 [7.9-14] ie 242% )

You said your T3 is 'in range ' , i wonder if you'd noticed a similar pattern in your T3 levels

[pennyannie]

Hello Fiftyone :

The accepted conversion ratio when on T4 - Levothyroxine only is 1 / 3.50 - 4.50 : T3/T4 :

With most people preferring come in at around 4 or under :

So, if you divide your T3 into your T4 that is your conversion ratio when on T4 only :

Generally speaking the higher the T4 the higher the T3, but providing the T3 is still in the range, and you feel better, it's seen by some endocrinologists, Professor A Toft, for one, to be acceptable to run with a higher than range T4:

It is T3 that runs the body and gives you your wellness : too high a level of T3 and you may experience hyper type symptoms and too low a level of T3 and you may well experience the equally disabling symptoms of hypothyroidism.

[fiftyone in reply to pennyannie]

just done the sums. My conversion rate is 3.8. That seems fairly normal then?

[pennyannie in reply to fiftyone]

Yes, could be, it's the right side of 4 but how do you feel ?

We all have our unique set point, and it's about where you feel at your best :

I appreciate this can be difficult as when being unwell, or undermedicated for any length of time we generally adjust and become accepting especially when told that we are " fine ' and possibly offered anti depressants as a consolation prize :

Normal is an opinion not a fact : and your normal may not be mine :

I'm with Graves post RAI thyroid ablation and managing lingering Graves, thyroid eye disease and hypothyroidism and now self medicating.

[tattybogle in reply to pennyannie]

I have the same issue with ratio's as you do with cut and paste

but i decided to try ... any way , it has just posed me another problem... which relates to 'ranges' (and i think 'fiftyone' has ft4 results using the same lab range as i do )

Compare these results and you'll see my quandry:-

tsh...........fT3................% ....................fT4................%......................conversion thingy.

0.05........5.2 [3.8-6] 63%..............18.8 [8-18] 108% ......................3.61* .......... * Edited

0.046.....5.1 [3.1-6.8] 54%............14.7 [7.9-14] 111%.................2.88*.............*Edited

My problem being ..... these results show effectively the same T4 and T3 levels, same TSH , same Dose, same %'s through range.

But because the fT4 range has changed so much i'm now dividing into 14 rather than 18 , so it changes the end result from 3.61 to 2.88 , a fairly significant difference .

Q1 )

am i doing it wrong ie. on calculator "5.2 / 18.8 = 0.2765 " Edit* yes i was

Q2 )

is it a big enough difference to matter anyway.

Q3 )

is this just more evidence to support my pet theory that the low /narrow [7.9-14] fT4 range distorts all our results when we do %'s and ratio's etc.

[pennyannie in reply to tattybogle]

Hey there Tatt ;

So if you round up the TSH it hasn't changed and nor has your T3 - but your body didn't get the memo that you now have to fit into a different range !!!!!

So if I divide your T3 into your T4 I get a conversion ratio of 3.61 ( 5.2 / 18.80 ) while with the second result it's coming in at 2.88 ( 5.10/14.70 ) :

It does matter if you are now told you are over the range and need a dose reduction of T4 as this will no doubt reduce your level of T3 which is only 54% through the range. and it is low T3 that causes the symptoms of hypothyroidism just as a high, over range T3 may cause symptoms of hyperthyroid.

If you feel better where you are stay put :

It's just another tool to quickly check how well you convert T3 -

Either way it shows good conversion and yes, to have any further value you would have to be compare using the same parameters and ranges either with percentages or this conversion ratio which I would think was based on a wider range than your last result.

In fact I find that a little strange as the T3 range is the one constant when the T4 range is given as 12 - 22 ?

Is that right ? the T3 range in the first set of results is 3.80 - 6.00 ?

[tattybogle in reply to pennyannie]

Yes correct . the ranges are exactly as written.

(I was putting the 5.3 into the calculator first , followed by / and 18.8 , hence me coming up with 0.27.

When you write 5.3 /18.8 .does that mean 'put 18.8 in first' ? )

[pennyannie in reply to tattybogle]

I go 18.80 divided by 5.30 : dividing the T3 into the T4 :

[tattybogle in reply to pennyannie]

Ah ok. (maths ...not my best subject )

[fiftyone]

Just fine but doctors get panicked cos my T4 is about 7 points above the range. I have to tell them to stop panicking.

[fiftyone in reply to fiftyone]

does that mean my conversion rate is entirely normal, high or low?

[pennyannie in reply to fiftyone]

Where is your TSH as that is generally what concerns doctors.

Look up on the Thyroid UK website who are the charity who support this amazing forum Professor A Tofts recommendations for treatment with T4 - Levothyroxine , where he states that some do need their T4 above range in order to convert sufficient T3 for their needs.

Sorry I can't help you find the article, but it's there somewhere - I don't understand the cut/paste/ link procedure :

[fiftyone in reply to pennyannie]

thanks for the info. My only interest at the moment is uderstanding conversion.

[tattybogle in reply to fiftyone]

so are your numbers something like T4 21 / T3 5.5 = 3.818 ?

(I think i was dividing my numbers the wrong way round before )

[fiftyone in reply to tattybogle]

MY T4 is 24 (range up to 16) and T3 is 6.3 (range up to 6.8)

[pennyannie in reply to fiftyone]

Where is your TSH ?

[fiftyone in reply to pennyannie]

0.005

[pennyannie in reply to fiftyone]

Ok - so you may well have a problem with your doctor as this TSH is below the reference range :

[fiftyone in reply to pennyannie]

what? you mean my doctor should intervene to bring my TSH up? Is this what you mean? <Edited by Admin> TSH only shows how much thyroxine hormone is in the body. I have lots. You can tell that by my T4 level and my T3. My TSH is working well.

It doesn't show what happens to the thyroxine or whether the body needs it. <Edited by Admin> Sorry if I've misundertood.

[pennyannie in reply to fiftyone]

I shall ignore your last comments as you have totally misunderstood and all I am simply saying is that doctors work to guidelines and generally speaking if your levels of TSH, T3 or T4 are out the range the doctor is obliged to look to adjust your medication to bring you back into range.

You may argue that the ranges and guidelines are not fit for purpose but that's a totally different subject, and on which I agree.

Please don't apologise ;

Thank you :

[fiftyone in reply to pennyannie]

But that's the problem I have all the time. Doctors looking at figures. My belief is they should try and find out why the figures don't match the reality. If the figures seem to show that I'm very unwell, there is something wrong, cos I'm not. Instead of trying to make me fit the figures, I wish they'd find out why the figures don't fit me!! Apologies for any offence. I just get a bit frustrated.

[SeasideSusie Remembering in reply to fiftyone]

fiftyone

If so, you're as stupid as some of them.

God. Glad you're not my doctor.

That's extremely offensive to someone who is trying to help you and these remarks contravene Posting Guidelines:

9. We want all members to be comfortable posting here. In order to ensure that any post or comment which causes alarm, harassment or distress to any person, whether or not intended by the poster, may be removed.

10. Please refrain from making derogatory comments about other HealthUnlocked groups, members or Admin of those groups.

Perhaps you would care to remove them yourself, if not then a member of the Admin team will do so.

[fiftyone in reply to SeasideSusie]

apologies. Remove them if you wish.

[tattybogle in reply to fiftyone]

"does that mean my conversion rate is entirely normal, high or low?"

so... Pennyannie says

"The accepted conversion ratio when on T4 - Levothyroxine only is 1 / 3.50 - 4.50 : T3/T4 "

As i understand it, this means;

3.5 = better (but still normal) conversion.

4.0 = average conversion.

4.5 = worse (but still normal) conversion.

So, your 3.8 is within 'normal ' ...and it is just within the better half of 'normal'

For Example, if T4 was 24 with T3 at 5.3 . you'd have conversion 4.52 (less good than the normal conversion )

If with T4 at 24 you got T3 at 6.9 , you'd have conversion 3.47 (better than normal conversion)

So, at T4 24 with T3 6.3 you had conversion 3.8

so that makes your conversion toward s the higher(better) end of 'normal'

But , as with anything to do with thyroid results in numbers , it's all theoretical , and means nothing without relating it to how you personally feel on those numbers.

In healthy people on no thyroid medication there is a pretty wide variation in their individual ratio's of T3 to T4 and also their levels of T3 and T4, and if you were to give them a different ratio/level of either T3 or T4 to their personal 'normal ' , they wouldn't function well or feel well , even if it did look 'fine' on paper.

Also it's difficult to get a good picture from just 1 set of results.

I have 5 set's of T4/with T3 results over a couple of years, and the ratios come out as between 2.8 and 3.6 .... ie. 'better' than yours is , but i've never been what you'd call 'well' on Levo . and i too seem to need fT4 over range to be even vaguely OK.

(Technically ,I don't know if it's a conversion 'rate' or a 'ratio' , there is probably a difference, but i'm a bit lost there)

Sorry if i've just confused you more .

I think i just had to write this down in an attempt to understand it myself.