Dangers of suppressed TSH

My doctor tells me that a consistently suppressed TSH level can cause serious health issues.

Is this correct? On what medical evidence is the idea based? Are there any published papers on the subject?

Thanks for your advice.

[StitchFairy]

What exactly does your doctor mean by 'supressed'? If he means a little under the reference range, then I'd ignore it. If your TSH is 'undectable', then it may be something to invesigate further.

[Hidden in reply to StitchFairy]

Thanks for your reply. My TSH was at 0.14 with a reference range of 0.3 to 3.18.

[SeasideSusie Remembering in reply to Hidden]

ScotPoodle

Suppressed is <0.1, yours is not suppressed it is classed as low.

[SeasideSusie Remembering]

ScotPoodle

If a doctor said that to me I think I'd be asking him to explain exactly what serious health issues he is talking about and provide the evidence. How can you look for papers if you don't know what issues you're looking for?

This article about Myths of Hypothyroidism is on ThyroidUK's website and one of them is about the myth that a suppressed TSH leads to Osteoporosis

thyroiduk.org/further-readi...

You might find these previous posts on the forum helpful

healthunlocked.com/thyroidu...

healthunlocked.com/thyroidu...

healthunlocked.com/thyroidu...

healthunlocked.com/thyroidu...

healthunlocked.com/thyroidu...

Also, Dr Toft, past president of the British Thyroid Association and leading endocrinologist, states in Pulse Magazine (the professional publication for doctors):

"The appropriate dose of levothyroxine is that which restores euthyroidism and serum TSH to the lower part of the reference range - 0.2-0.5mU/l. In this case, free thyroxine is likely to be in the upper part of its reference range or even slightly elevated – 18-22pmol/l. Most patients will feel well in that circumstance. But some need a higher dose of levothyroxine to suppress serum TSH and then the serum-free T4 concentration will be elevated at around 24-28pmol/l. This 'exogenous subclinical hyperthyroidism' is not dangerous as long as serum T3 is unequivocally normal – that is, serum total around T3 1.7nmol/l (reference range 1.0-2.2nmol/l).*"

He's unlikely to say that if there is evidence it will cause osteoporisis (or AF).

Other than that, what is he talking about?

[Hidden in reply to SeasideSusie]

Thanks for this and for your most recent comment about suppressed being <0.1.

My doctor wrote that 'there are more serious complications of being over active such as atrial fibrillation which can cause strokes, brittle bones, irreversible eye problems and sometimes skin problems'.

He connects a low TSH with being over active however I am not convinced that the two are automatically connected and I think he is being overly cautious.

I'll certainly look at the references you sent as I want to engage my doctor in a reasoned debate based on the evidence.

[SeasideSusie Remembering in reply to Hidden]

ScotPoodle

My doctor wrote that 'there are more serious complications of being over active such as atrial fibrillation which can cause strokes, brittle bones, irreversible eye problems and sometimes skin problems'.

The AF and osteoporosis are covered in my links above. I don't know about eye problemsnor skin problems. I've not heard this before. As I said, ask him for the evidence.

Obviously this is something you need to look into yourself and make up your own mind based on the evidence; however, maybe also consider the experience of members here.

I have been diagnosed/treated for hypothyroidism since 1975. I started to keep a record of my results in 1995. Results at that time on Levo only:

TSH: 0.5 (0.0-6.0) with FT4 very slightly over range, felt OK, GP had no problem with results.

In 1997 TSH: 0.02 (0.27-4.20) with FT4 close to top of range. Again GP had no problem with results.

In 1999 TSH: <0.02 (0.27-4.20) with FT4 very slightly over range, again GP had no problem with results.

Became ill with 3 viral infections which followed each other rapidly and screwed everything up.

Tried NDT/T3/different combinations for a couple of years, went back to Levo in 2002.

2002-2014 on all but two occasions when my TSH just scraped into range, it was suppressed on Levo only. FT4 always high or over range but FT3 never tested.

I tested myself, found I was a poor converter and since 2016 on Levo plus T3 so expect it to be suppressed. Since 2002 typical results for TSH, depending on how low the different labs' equipment measures:

0.01

<0.01

0/02

<0.02

0.008

<0.005

So for 19 years my TSH has been suppressed. I'm not dead yet, I don't have osteoporosis, nor AF, nor eye problems nor skin problems.

He connects a low TSH with being over active however I am not convinced that the two are automatically connected and I think he is being overly cautious.

No, of course they're not automatically connected. When you have hypothyroidism you cannot become overactive, it's a physical impossibility for your thyroid to regenerate and suddenly go the other way. You can be overmedicated, but that is not shown by the TSH, it's shown by an over range FT3. Dr Toft's article tells us that we can have a suppressed TSH, even an over range FT4 as long as T3 or FT3 are within range. The British Thyroid Foundation says something very similar:

btf-thyroid.org/thyroid-fun...

How can blood tests be used to manage thyroid disorders?

.....

Occasionally patients only feel well if the TSH is below normal or suppressed. This is usually not harmful as long as it is not completely undetectable and/or the FT3 is clearly normal.

There are also certain patients who only feel better if the TSH is just above the reference range. Within the limits described above, it is recommended that patients and their supervising doctors set individual targets that are right for their particular circumstances.

Why doctors/endos don't know about this I don't understand, and if they do know about it why do they ignore it?

[Hidden in reply to SeasideSusie]

Thank you!

[bantam12 in reply to Hidden]

My TSH has been around 0.03 for many years and I have developed atrial fibrillation amongst other heart problems, whether that's because of my low tsh nobody can tell but my Cardiologists do know that the heart problems associated with hyperthyroidism (which I've had since a child) are a high risk factor.

[Hidden in reply to bantam12]

Thanks bantam12.

[SlowDragon Administrator]

Post from 2 months ago

healthunlocked.com/thyroidu...

Have you had FULL thyroid and vitamin testing privately to see exactly what you levels are?

For full Thyroid evaluation you need TSH, FT4 and FT3 plus both TPO and TG thyroid antibodies tested.

Also EXTREMELY important to test vitamin D, folate, ferritin and B12

Low vitamin levels are extremely common, especially with autoimmune thyroid disease (Hashimoto’s or Ord’s thyroiditis)

Recommended on here that all thyroid blood tests should ideally be done as early as possible in morning and before eating or drinking anything other than water .

Last dose of Levothyroxine 24 hours prior to blood test. (taking delayed dose immediately after blood draw).

How much T3 are you currently taking

Do you normally split the dose

Day before test split dose of T3 into 3 smaller doses, taking at approx 8 hour intervals, with last dose 8-12 hours before test

This gives highest TSH, lowest FT4 and most consistent results. (Patient to patient tip)

Is this how you do your tests?

Private tests are available as NHS currently rarely tests Ft3 or all relevant vitamins

List of private testing options

thyroiduk.org/getting-a-dia...

If you can get GP to test vitamins and antibodies then cheapest option for just TSH, FT4 and FT3

£29 (via NHS private service ) and 10% off down to £26.10 if go on thyroid uk for code

thyroiduk.org/getting-a-dia...

monitormyhealth.org.uk/

Medichecks Thyroid plus antibodies and vitamins

medichecks.com/products/adv...

Blue Horizon Thyroid Premium Gold includes antibodies, cortisol and vitamins by DIY fingerprick test

bluehorizonbloodtests.co.uk...

When supplementing vitamin D test twice year

NHS easy postal kit vitamin D test £29 via

vitamindtest.org.uk

[Hidden in reply to SlowDragon]

Thanks SlowDragon, this is very helpful.

[tattybogle]

You might find these posts useful in the next round of 'low TSH' conversations with GP. They contain some interesting discussions and also links to evidence from a large long term study which found risks of TSH between 0.04 and 0.4 are *no greater than risks of 0.4 to 4 ( *roughly* i'm not awake enough enough to quote it accurately just now

healthunlocked.com/thyroidu... risks-of-suppressed-tsh-analysis?

healthunlocked.com/thyroidu... tsh-and-the-more-mature

[Hidden in reply to tattybogle]

Thank you tattybogle.

[Jazzw]

Unfortunately, the real state of play is that a doctor consistently obsessed with the idea of a suppressed TSH being bad for you is dangerous to your health…

Shouldn’t be looking at it in isolation. If your FT3 and FT4 levels are in range a suppressed TSH doesn’t mean you’re overmedicated.

[Hidden in reply to Jazzw]

Thanks Jazzw. A good point.

[McPammy]

My sister has to have her TSH suppressed constantly as she had thyroid cancer. Her endocrinologist has never explained to her the dangers to her health on suppressed TSH. Yet when I see my NHS endocrinologist he says he will stop my T3 medication prescriptions if my TSH goes suppressed as it’s bad for my health. They just contradict themselves.

[Hidden in reply to McPammy]

Thanks McPammy, did he explain why he thinks it's bad for your health?

[McPammy in reply to Hidden]

No he didn’t. But it did scare me only as I don’t want my T3 medication stopped. So far my TSH has only gone suppressed just once in 2 years and 18 blood tests of T3. It’s normally hovering around 1.00. I feel very well and due another blood test this Friday. I’ll ask him next time I see him.

[Hidden in reply to McPammy]

Thanks, I'll be interested to hear his reply.

[McPammy in reply to Hidden]

Yes it will. Also will be interesting what my sisters reply will be.

[tattybogle in reply to McPammy]

The reason for TSH supressive doses of thyroid hormone in patients who had thyroid cancer is to stop the thyroid from having any activity , as i presume if it is active then that could stimulate any remaining cancer to regrow. ( i think the more recent guidance is that they don't have to continue TSH supression forever)

So in those cases, the risk of cancer recurring is greater than the risks associated with higher doses of T4/3 that lead to TSH supression.

So from that perspective it's not contradictory to say cancer patients can have supressed TSH, but the rest of us can't .

(I don't entirely agree with that perspective, i think they have got the 'risks' associated with low TSH (for the rest of us) all wrong, and should look at fT4/3 not just TSH)

[McPammy in reply to tattybogle]

HiYes, I agree about keeping it suppressed to stop any further reactivating of cancer.

I wonder how long that should be applied for in years. My sisters thyroid cancer was in 2013 so 8 years now. They have never explained to her about any negative symptoms she may have being suppressed and over T4 levels and she has a lot of them, and what to possibly expect.

My own TSH is 95% of the time around 1.00 now I’m on T3 Liothyronine.