Every second person who comes into my clinic has some sort of thyroid dysfunction (or so it seems – I might be exaggerating slightly, but you get my point). Sadly, most of these women (it does affect men too) have been dismissed by a GP as ‘fine’ when they know they are ‘not fine’. Why? Because standard thyroid testing gives an incomplete picture of thyroid health and honestly, in most cases, it’s completely inaccurate. I call it “thyroid madness” because the system is letting us down.
In this blog post I will explain the basics of thyroid hormones and the importance of proper testing.
Thyroid hormones 101
Here is a basic guide to your thyroid hormones, what they do and why we need to test them.
Thyroid stimulating hormone (TSH)
This is the gold standard for testing according to your GP. Sadly though, it’s the most unreliable marker when it comes to the health of your thyroid (as you will soon see).
TSH is a signalling hormone that tells your thyroid to produce T4 (see below). If T4 is LOW then feedback mechanisms will tell the hypothalamus and the pituitary gland that we need more T4 so TSH gets up-regulated. If T4 is HIGH then those same mechanisms work to dial down TSH.
So in theory, if you have high TSH, you have low thyroid function (or hypothyroidism) and if your TSH is low then you have an over-active thyroid (hyperthyroidism). In theory….
T4 is your storage form of your thyroid hormones. It does not exert any metabolic effects when it is in this form.
If you are taking thyroxine, you are getting T4 only.
T3 is your active thyroid hormone. It is responsible for all those beautiful effects on health and metabolism. We NEED good levels of T3 and yet this is rarely tested. If you have issues converting T4 to T3, then you are going to feel lousy.
For me, this is perhaps one of the most important markers of thyroid function.
Some patients take T3 as prescribed by a GP, but this is typically the exception and not the rule.
Reverse T3 (rT3)
Reverse T3 is what I (crassly) call the ‘bastardised’ version of T3, in that there is one small structural change to active T3 that effectively renders it useless. It can happen when your adrenals are working overtime pumping out cortisol to help you deal with stress (this is just one example). Sadly, your body still recognises it as active T3 so it can distort your TSH levels dramatically (and this is why TSH isn’t the bees knees when it comes to testing).
rT3 is NEVER tested by a GP. You can pay an additional fee to have this added to your thyroid panel if you want it checked. TIP: If you do, you need to make sure it is taken from the same blood sample as the rest of your thyroid panel, otherwise the result on its own is largely meaningless.
If you have elevated antibodies, this is a sign that you probably have an autoimmune disease e.g. Hashimoto’s (hypothyroid) or Grave’s (hyperthyroid). This means you have an overactive immune response against your own body’s cells – in this case, the thyroid.
Guess what? Your GP often won’t test these either because it won’t change their treatment (thyroxine). If they do test it to confirm a diagnosis, they rarely retest (because again, it won’t change their treatment).
Thyroid testing 101
If your GP orders a test for your thyroid, it is typically only TSH. Sometimes (if you are lucky) you might get T4 tested as well, but in my experience this is a rare occurrence. What this means is that you are only getting a small part of the thyroid picture and this means that the majority of thyroid issues are missed completely.
I don’t blame the GPs. They have restrictions on what they can do and really it’s only when TSH is way out of the range that they will dig a little deeper and look at….T4. Maybe T3. Sometimes antibodies. Never rT3.
This is because they are only looking for overt disease – which they can then treat with a drug (e.g. thyroxine).
The take home message here is that if your TSH is “normal”, it doesn’t mean you don’t have thyroid problems.
The classic one is low or normal TSH (with low T4 if you are lucky enough to have it tested) – when you dig a little deeper, it can often show high levels of rT3 which is reducing our T3 (active hormone – this is the one we want!) and throwing the feedback loop out of whack.
If you have been taking thyroxine for a while, your GP is telling you that you are ‘fine’ because your TSH (and maybe T4) is “in range” but you still feel terrible, then you need to do further investigations.
So what can you do?
My advice is always to see a qualified Naturopath who can determine whether a full thyroid panel is warranted. If it is, we can order it privately at an additional cost, but let me tell you it’s well worth it. A Naturopath can check to see how well your body is converting T4 to T3 and what impact rT3 and antibodies are having on your thyroid. We can also address other contributing factors to thyroid dysfunction such as nutrient deficiency – especially iron, selenium and iodine (to name just a few).
Don’t put up with feeling crap. You deserve to feel good!