Am I converting T4 to T3?: I still have terrible... - Thyroid UK

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Am I converting T4 to T3?

Mitsy123 profile image
7 Replies

I still have terrible fatigue and can't lose weight, even though I diet and exercise every day. My Endo told me all my levels are good, but which test measures if I'm converting T4 to T3?

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Mitsy123 profile image
Mitsy123
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7 Replies
Clutter profile image
Clutter

Mitsy123, you need TSH, FT4 and FT3 tested. If TSH is low, FT4 high, and FT3 low it indicates poor conversion.

jacrjacr profile image
jacrjacr

tsh , free t3 , free t4.......

Glynisrose profile image
Glynisrose

There is no accurate test to see if you are converting. You use up T3 every time you exercise so there is a chance that you are using up all your available T3.

Mitsy123 profile image
Mitsy123

Thanks for the replies: my latest test results were

TSH 0.65

FT4 16.1

FT3 4.1

Any more thought on these?

Thx x

greygoose profile image
greygoose in reply to Mitsy123

Can't think about them without the ranges. :)

When you say you are 'dieting', what exactly do you mean? Low calorie? Low calorie diets will affect conversion. You need those calories to convert!

Dieting and exercising are not recommened for hypos. As Glynisrose said, exercising uses up your T3, and dieting prevents you from making more.

And, what's worse, neither of them will help you lose weight when you're hypo, because your weight gain has nothing to do with calories.

It's due to your compromised metabolism due to low T3. The only way to lose weight is to raise your T3 levels. :)

Mitsy123 profile image
Mitsy123 in reply to greygoose

Hi, thx so much for replying.

I'm shocked, my Endo has never mentioned this and my GP recommended exercise. So, do I just eat normally? When I do that, I usually pile on the pounds.

These are the ranges:

FT3. 3.5 - 6.5

FT4. 9 - 24

TSH. 0.35 - 5

Do u have any suggestions on what I should do now?

Thx.

lozon profile image
lozon

You might be reverse T3 dominant and converting T4 to reverse T3 which is not only inactive but blocks the action of normal T3.

You need to check reverse T3 levels and if elevated, stop T4 and begin T3 only.

Take no T4, no Armour thyroid, just T3 one time a day.

The half life of T3 is 2.5 days so once a day dosing is good.

If you're reverse T3 dominant the more T4 you take ,the more reverse T3 you make and the more more hypothyroid you become.

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