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T3 and TSH test results ...what should they ideally be ?

Does anyone know the optimal results for a Hashimotos person who is on NDT ?

My last results showed a T3 of 5.2 (3.1-6.8 )

And a TSH of 0.05 (0.27- 4.20 )

I’m asking as I was given to understand by someone that my t3 could do with being a little higher,

And as regards the tsh, I have long thought..known....that the tsh WILL be very low, suppressed, and that for many is the most comfortable...I’ve even been 0.01...

BUT...recently , someone a doctor who I thought knew everything, commented that my t3 is rather too high and the tsh is rather too low.

Just the kind of thing a hypo already confused person needs 🙃

Any comments please ?

11 Replies

I started NDT five weeks ago under the supervision of an NHS Consultant. His advice is the T3 and T4 must be in the top third of the reference range and TSH registering in the reference range not below it.


Ok..thanks...but that’s not what I’ve always gone by ! Not sure I would take all and NHS consultant says anyway !.

That’s not being cynical, it’s just that I don’t think the NHS has the true measure of things when it comes to the thyroid.

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Of course it depends on relief of your symptoms and that’s what is important. However so much emphasis is made on the TSH being above 0.2 or in my husbands reference range 0.4 and doctors start reducing doses to achieve this. His advice is that the TSH number does not matter in his practice but he prefers it not to be in the negative scale. The results for T3 and T4 can go to the maximum of the scale but not over it. I was stunned that an NHS endo would totally oppose my GP’s view and support NDT. I think he is pretty good but time will tell on his advice on the next tft results.


Yea, there's definitely some suspicious points in what you've described! Several of the things he wants cannot all happen at the same time.


Whatever the range is when your symptoms are reduced to nil, or close enough to, That is the right range for you. Trust how you are feeling, write down your main symptoms and gauge them over time so you Know and you can Articulate to your doctor how you’re actually feeling and know if you’re improving or not.

You might find this article interesting, someone posted it here recently. I’ve set it to my GP and Endo — all about being “in range”


“Thyroid hormone replacement – a counterblast to guidelines”



Well thanks for this Blue Bee..you’ve written simply but clearly and helpfully..Thanks.

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The link given above is by Dr Toft, who is an Endocrinologist/Physician in Scotland and he is also Physician to the Queen when she's there.

I'd definitely give a copy to my doctor and highllght the following from the above link:-

It is as if guidelines, like the tablets given to

Moses on Mount Sinai, have been carved in stone for a new

generation of doctors that seems duty-bound to follow each

edict slavishly. The impression is that young physicians have

ceased to think, ceased to challenge received wisdom and

ceased to recognise that patients come to the consultation

as individuals, expecting to benefi t from the opinion of an

open-minded and experienced professional.

Simply because no two patients present in the same

manner, guidelines, by their very nature, are the antithesis

of the art of medicine. We cannot afford to underestimate

the level of frustration among patients, exasperated by the

‘one solution fi ts all’ philosophy. It was put to me recently

by a patient that, if governments wished to save money

from their healthcare budgets, they should invest in flocks

of African grey parrots, as these repetitive mimics could

easily replace the current breed of doctor in the consulting

room. She had a point.


When you are taking NDT or T3, your TSH is more than likely going to be suppressed - there is absolutely no scientific justification for trying to keep it in-range. It doesn't matter. It's low because you don't need it anymore.

Your FT4 is going to be low, too, because you don't need as much of it, and the body only hangs on to what it needs. Trying to raise the FT4 to the top of the range, when taking T3, is a waste of T4 and only complicates matters. It's when you're on T4 monotherapy that it needs to be high.

Your FT3 should be wherever you need it to be, where it makes you feel well. There's no hard and fast rule for an optimal number. Obviously it shouldn't be too far over-range, but some people do need it slightly over-range to feel well. :)


I'm glad greygoose has answered your query because she has always seemed to me to be the voice of reason on this matter...in my experience, she is a wise head on a swan-like neck!

...someone a doctor who I thought knew everything, commented that my t3 is rather too high and the tsh is rather too low. I thought my daddy knew everything; I won't elucidate but there was a while where I ignored the science and relied upon his wisdom. It's tough when our Mr/Dr/Mrs Know doesn't come up with the goodies. RIP fella, miss you :)


Well, your Free t3 is withing range so it can't be too high. It always amazes me that doctors will refuse to treat when TSH is way over range and yet panic when free t3 and t4 are over halfway up the range. If you feel good, just stick with your current dose.


I agree with all the posters who have said that symptoms are more important.

But I always think of the rule of thumb with freeT3 is that it should be in the top third. I always say 'rule of thumb' because I hope that makes clear it's just a very rough guide with many exceptions. Doctors often keep people with a much lower freeT3, which is one of the reasons I think it's important to say it - you're certainly 'allowed' to go all the way to the top if that's what you need in terms of symptoms.

Personally, I now have over range freeT3, and have only started being able to get up and move around a biy since having it very high. I believe I have some form of thyroid hormone resistance - issues with the hormone getting into the cells. So there are always big exceptions when people have slightly different conditions.

This means TSH is often suppressed. One member above mentioned that their doctor wanted freeT3 fairly high but the TSH within range - this is a fantasy. TSH gets very low well before freeT3 is at the top.


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