What do we make of these “optimal” ranges?

[Lotika]

Hi -

I’m interested in the following extract from a book by a well-known thyroid writer:

“If you have had a full panel conducted, be sure to check that they fall within optimal levels; a TSH below 2, Free T3 within the top quarter of the range and a Free T4 mid-range or higher.”

We’re all different of course. The idea of having my fT3 within the top quarter of the range feels so far out of reach that I’m almost tempted to laugh! I’m on an NHS T4/T3 trial and at my last test, fT3 was still less than 50% through range, but a lot of my aches and pains have gone, physical and psychological. That has of course been an improvement from 11%(!) but fT4 has fallen off a cliff, so that is where I am focusing my attention. I have been working on the principle that I had more energy on levo only, so my instinct is to raise fT4 back to that level... anyway, more about me when we get my next bloods; I’m more interested in the general assertion.

I was just wondering what people on combination therapies thought of the ranges from their own experiences? As an aside, I can’t help feeling that very few people on T4 monotherapy are ever going to achieve fT3 that high... therefore, if our writer is correct, it follows that almost nobody can do well on levo alone... ?! I guess I don’t *know* that people on T4 monotherapy can’t get fT3 that high, because almost by definition they won’t be posting here... but I find the assertion that we all need ft3 that high open to debate...

What do you think?

[m7-cola]

I don’t have ‘faith’ in blood test ranges. They are only a guide; no blood test can show how much of the thyroid hormone medication we swallow has reached our cells. I prefer to rely on my symptoms and expect my endo to listen to my reports.. Unfortunately many here need to satisfy their doctors with ‘blood test results’.

[Lotika in reply to m7-cola]

Ha ha! I don’t expect NHS endos to listen to me by now, sadly. Agreed re what reaches the cells being more important than what the bloods say and that the bloods aren’t the whole picture, although the bloods definitely have a place and can be indicative, in my view.

[jimh111]

I distrust anyone who refers to 'optimal' levels, it's usually a hook to get patients to subscribe to websites. From a science point of view somewhere near the middle of reference intervals will be appropriate for most people. However, some of us need higher and some lower levels. Advice to target higher levels is not only wrong, it is dangerous. Some will need these high levels, or even higher, but many will not.

[Lotika in reply to jimh111]

I hear you. I’m inclined to believe the writer means well in this instance, though.

I also find myself agreeing with you that advice to target specific ranges can be a bit dodgy, actually, now that you say it. I think what we have to do is to trust our own instincts. My instinct says I should be getting fT4 back to a reasonable level. That having been said, having fT4 mid-range and fT3 really high might be worse, as good, or better and I will never actually know unless I try both and write a symptom diary, given that remembering how one felt is a bit of a challenge with hashis/hypo! Although that being said, I can’t imagine wanting to take the risk of feeling worse if I finally found something which felt about right.

[DippyDame in reply to Lotika]

Hmmm! So who is this, 'well-known thyroid writer" whose book you quote from?

Just curious!!

[Lotika in reply to DippyDame]

The choice not to say was deliberate, mainly because I broadly respect, appreciate and value their book (so far) so I want to be gentle about examining a part of it which I’m not sure about! I will say that I think the interpretation of optimal ranges is potentially led by their own treatment preferences... but that happens to us all, I suspect! And I haven’t finished the book yet, so I hesitate to draw any conclusions or lead anyone else towards one, one way or another, until I have!

I can say that it isn’t Dr Barry Durrant-Peatfield, who I’m a bit in love with since reading his book! He has one or two slightly questionable moments (in my humble opinion) around goitrogens and T4/T3 combination dosing particularly as I recall, but I thought it was 90% useful and loved the fact he was so on the side of the patient generally! I actually had tears in my eyes thinking “here’s a medic who understands us, how amazing... and who cares enough to empower us by writing an informative book.” I should perhaps compare with whatever he said on optimal levels, if anything. I don’t remember... And frankly my ability to absorb information on my current dosage is pathetic, so when I say I’m reading something, I’m mainly running my eyes over the words!

Just editing to say that Dr B D-P isn’t drawn into a discussion about optimal ranges because he says it’s about what’s in the cells, not the bloods, so he’s very big into pulse and basal body temperature. Wise man!

[DippyDame in reply to Lotika]

OK...Happy reading!

[guysgrams]

I'm on combo T4/T3 and have been now for over 2 years. Prior to that T3 only for about a year and before that T4 only. When on T4 only I felt like crap. Since I've been on this combo my FT4 is at the bottom of range and hasn't really moved much. My FT3 is close to midway in range. I can tell you I feel much better in so many ways since going on the combo. I so needed the T3 as I do not convert well. I finally gave up on endos/doctors and now see a functional medicine doctor who has been extremely helpful to me. I go more on how I actually feel than just the blood work. I can tell when things aren't quite right and the labs always confirm it for me.