Why Hypothyroid may exist even when results are "clear!"
Updated: Oct 20, 2019
So it’s blog time again & while I knew I wanted to talk about the thyroid I got a bit overwhelmed with what aspect, as it’s a vast topic. Then I thought about what I really wanted my patients to know. I wanted to give them enough knowledge to advocate for themselves when they feel like somethings off but they’re told their blood tests come back fine.
So let’s back up a bit & let me introduce you to the thyroid.
The thyroid is a butterfly shaped gland in our neck that produces hormones which power all the cells of our body. Thyroid hormones regulates metabolism, so if there’s not enough hormone you can feel sluggish & hold on to weight & if there’s too much you can get anxiety & heart palpitations. This is one of the reasons the thyroid is known as the thermostat of the body.
SYMPTOMS OF THE THYROID:
* fatigue even after sleeping 10 hours
* brain fog
* weight that doesn’t come off with diet & exercise
* hair loss
* feeling cold all the time.
* You must be low in iron.
* You must just be exhausted from having a new baby.
* These are some of the things that thyroid disease, especially hypothyroid is mistaken for.
Patients are coming in with symptoms typical of hypothyroid & yet they’re told their thyroid is fine, that they’ve had the testing & that their thyroid is within the “normal” range.
Here’s the problem with that. In most instances, the only thing tested is TSH (thyroid stimulating hormone) which isn’t actually a thyroid hormone! TSH is a pituitary hormone which tells your thyroid how hard to work, ie/ how much thyroid hormone to make. So if TSH is too high it tells us that the pituitary is having to send a big signal in order for the thyroid to do its job. This is what happens in the case of hypothyroid.
How can we get a true reading on the thyroid from only testing a pituitary hormone?!
The other aspect of only testing TSH is that you’re assuming the reference ranges are correct, right? In Australia most of the Pathology ranges for TSH are 0.5 to 5 Umol/L. However I’m going to infer that like America these ranges were developed using readings taken from people with thyroid disfunction. Meaning that the reference ranges may not be a true representation of the population but rather skewed by people who already had thyroid issues, leading to a reference range that is far too wide.
We also have to be aware that reference ranges are not optimal ranges. People can be having symptoms within these ranges & commonly do. I want my patients to be aiming for optimal range. For my patients, a TSH of over 2.5 has me looking into further thyroid testing to rule out hypothyroid.
Yet here’s the thing. I’ve seen patients with a TSH in optimal range who have hypothyroid. Which is why we need to test the actual thyroid hormone itself.
Conventionally, if TSH is too high then T4 will be tested. T4 is the storage form of thyroid hormone. Unfortunately in a lot of cases this is where testing stops. If T4 is within the reference range (again, too wide) that’s usually that. If it’s under the reference range in conjunction with a high TSH & hypothyroid is diagnosed, the typical treatment is thyroxine. Thyroxine is a synthetic form of T4. So what happens is the patients TSH lowers into range & they think it’s all sorted even if they’re still getting symptoms.
What doesn’t get explained is that T4 has to be converted to T3 which is the active form that our body uses. So giving T4 doesn’t necessarily mean that the body is able to convert it to the usable form. For some, they are able to convert it, for others their TSH & T4 may be fine but they are low in T3 & thus have symptoms which may be dismissed or mistaken for something else.
Then there’s thyroid antibodies & reverse T3 but that’s for another time. I think I’ve probably overwhelmed you enough.
So what I recommend if you want to look into your thyroid further is using an independent Pathology lab.The one I really like for thyroid testing is i-screen. There’s the basic thyroid test, which tests TSH, free T4 & free T3 & the more comprehensive one that also tests the two most common thyroid antibodies.
It’s super easy to use, you pay online, they send you the form, you take it to one of their collection centres near you, and a day or two later the results are emailed to you with a colour graph to see where you sit in the range.
Here are the links:
Basic test –
Comprehensive test –