Understanding Thyroid Test Results

This is the first time I have posted on this site. I have had hypothyroidism for 17 years now and had yearly blood tests. I must admit I have never understood what the result has meant other than the GP saying it's satisfactory. My recent test was Serum TSH level 2.14 mu/1. This means nothing to me and wondered if you would kindly explain to help me understand. I take 75mcg of Levothyroxine having reduced from 100mcg a few years ago. I get very tired, brain fog and all the other usual symptoms associated with this condition. I have just started to take B12 as I read on this site it can help. I have also started taking my Levothyroxine tabs at night and have found I sleep so much better. Look forward to any replies.

[greygoose]

Hi Rozzy57, welcome to the forum.

TSH is a pituitary hormone, not a thyroid hormone.

When the pituitary senses that there's not enough thyroid hormone in the blood, it increases out-put of TSH - Thyroid Stimulating Hormone - to stimulate the thyroid to make more hormone.

When it senses that there is enough thyroid hormone - T4 and T3 - in the blood, it reduces production of TSH.

Therefore, doctors have decided that the TSH 'tells them all they need to know'. But, they are wrong because that is assuming that the pituitary always works perfectly, but it doesn't. What's more, it only reacts to what is in the blood, not what is getting into the cells. So, you could have a very good TSH but still be hypo. But doctors don't know enough about thyroid to understand that. They should not be dosing by the TSH.

Not only that, but there is also the thorny question of the blood test 'ranges'. Usually, the range for TSH goes up to about 4/4.5 - I've even seen it as high as six! And, as doctors are not trained to interpret blood test results, they think that anything within the range has to be good.

However, the TSH of someone with no thyroid problems (euthyroid) would be around 1, never over 2, and you are hypo when it reaches 3. So, your TSH is far from being satisfactory, it is too high.

Add to that the fact that hypos usually need their thyroid hormone levels higher than euthyroid, so their TSH is usually lower than 1. But doctors don't understand that either.

With a TSH over 2, you need an increase in dose. 75 mcg is only a tiny dose - not much more than a starter dose. So, you must feel pretty bad, no? But I don't know how you're going to explain that to your doctor without making him feel ignorant - which he is, of course, but you can't tell him that.

You also need full thyroid testing to see the full picture:

TSH

FT4

FT3

(the F just stands for 'Free', meaning that it is available for use by your body)

TPO antibodies

Tg antibodies (unless you know that you have Hashi's?

vit D

vit B12

folate

ferritin.

I have just started to take B12 as I read on this site it can help.

Well, it can help if you need it. But won't do anything for you if you don't - and same goes for all nutrients, which is why we recommend testing them.

What's more, there are 8 B vitamins in total, and they all work together, so need to be kept balanced. So, just taking B12 is not going to do much for you even if you do need it. You need to take a B complex, not just one isolated B vitamin.

It also has to be the right type of B12: methylcobalamin. Not cyanocobalamin. Which is yours?

[Hidden in reply to greygoose]

Many thanks for your kind reply. That has certainly made things clearer. I think I will query things my GP about the dosage of levo I am on as I do get so tired every day and brain gets so foggy. Are there doctors that are specialists in thyroid treatment that you can have appointments with in the UK?

[greygoose in reply to Hidden]

Not that I know of. A thyroid specialist is a very rare bird in all countries. There might be more in the US, but I haven't heard anyone singing their praises!

Maybe someone else reading this thread will come up with a thyroid specialist. But they will have to PM you because we're not allowed to discuss individual doctors on the open forum.

[Hidden in reply to greygoose]

Thanks so much for your help. I will have a look around where I live and hopefully will find one

[helvella Administrator Thyroid UK]

Sleeping better! That is great. It is one of the many difficulties of thyroid treatment, you (and I) find it helps sleep. Others find taking at bed-time ends up causing them not to sleep well.

Not sure if you saw the link below?

helvella - Bed-time dosing of levothyroxine

Discussion about taking levothyroxine at bed-time. Several linked references to relevant papers.

helvella.blogspot.com/p/hel...

[Hidden in reply to helvella]

Thanks for your reply. Having taken tablets morning and evening, evening is so much better for me.