Link of low FT3 to Alzheimers onset: Oh dear... - Thyroid UK

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Link of low FT3 to Alzheimers onset

diogenes profile image
47 Replies

Oh dear, sometimes I come across a depressing paper which all the same is informative. This one links Alzheimer onset likelihood to FT3. Hope I haven't upset people with this.


Low serum concentration of free triiodothyronine (FT3) is associated with increased risk of Alzheimer’s disease

PatrickQuinlan, AlexandraHorvath, AndersWallin, JohanSvensson


Prospective study in a single memory clinic (n = 302).

Mean follow-up of 2.8 years.

Serum TSH, FT4, and FT3 were assayed in subjective or objective cognitive impairment.

Low serum FT3 associated with increased risk of progression to Alzheimer’s disease.

Serum TSH and FT4 were not associated to the risk of conversion to dementia.

47 Replies
LapisSW profile image

Thank you so much for this Diogenes. As a nurse and T3 user, I have long suspected something like this.

Katepots profile image

I think low T3 is the onset to many diseases, it seems such a key hormone to health.

Alzheimer’s, ME, CFS, Autism, heart disease, liver disease, renal disease...

I can’t understand how the medical world/media are not behind us in our fight.

m7-cola profile image
m7-cola in reply to Katepots

I don’t think they’ve joined the dots!

jgelliss profile image
jgelliss in reply to Katepots

Oh the contrary . They are very well aware how much T3 or lack of it affects every part of our well-being . The Big problem is BIG PHARMA . BIG PHARMA wants a Sick Society and a dummied down society . It's in their Interest . It's very simple . Big Pharma is in the pockets of greedy Medical Academia and Dr's and Politicians . They get to sell all kinds of meds . Tranquilizers , BP pills , Sleeping pills , Cholesterol pills , Pain pills , Digestive pills , Uppers Downers and anything in between .

If patients heal with T3 then they can't sell all he other pills . It's all about M-O-N-E-Y .

Judithdalston profile image

I had wondered....13 years of known low FT3 and I sometimes have had flashes ‘is this Alzheimer’s /dementia?’ when i’m searching for an everyday word....fortunately watching TV quiz shows demonstrates my ‘little grey cells’ aren’t bad , just slowish! I remember a not dissimilar paper / result re long periods of low FT3 and heart problems.... when will endos and other doctors realise how important T3 is?


jgelliss profile image
jgelliss in reply to Judithdalston

I ask the same ??????

m7-cola profile image
m7-cola in reply to jgelliss

Me too!

Angel_of_the_North profile image
Angel_of_the_North in reply to Judithdalston

It's aphasia when you know it's a thing you ride with wheels and pedals but you can't remember "bicycle". It's a complete pain in the part of your body you sit on.

Judithdalston profile image
Judithdalston in reply to Angel_of_the_North

Unfortunately wouldn’t remember that, but definitely have it yet can remember weird facts!

Kitten44 profile image

Having suffered the dreaded "brain fog", and sometimes feeling right out scared and wondering, is this what dementia feels like? Am I going mad?, it seems rather logical to make the connection between low T3 and Alzeheimer's and other forms of dementia or loss of mental capacity.

Musicmonkey profile image

As I have DIO2 gene which affects conversion from T4 to T3, I feel I have always suffered with a bad memory. Many people say you don't lose your long term memory with age, but I have forgotten so many things, like places I've been on holiday, names of my favourite songs, favourite films, names of friends from my past, etc. Knowing I have this faulty gene makes me wonder if this is why because I guess my T3 will always have been on the low side until supplementing it.

Not good news diogenes but useful to know nevertheless.

TSH110 profile image
TSH110 in reply to Musicmonkey

You would have been ok when your thyroid worked it just makes more T3 to compensate the problem is T4 monotherapy for us DIO2ers we can no longer compensate and end up lacking T3 and suffer with stuff like poor memory, heart pains.....and lord knows what else ☹️ I only stuck it two years and swapped to NDT - my problems greatly reduced, very rapidly.

dolphin5 profile image

It’s all so scary! But I appreciate you letting us know. It’s all more info for our doctors. Thank you!

UrsaP profile image

linda96 One for you?

UrsaP profile image

My memory is rubbish! has been for years. I can't remember half of the important aspects on my sons childhoods. Half the time I cannot remember what I was doing yesterday or last week. Hubby goes mad, gives me something, I put it in a pocket or bag. He asks for it back 5 mins later for some reason, I can't even remember him giving it to me!! Needless to say he keeps hold of things himself now. I don't think it has improved much with T3.

TSH110 profile image
TSH110 in reply to UrsaP

That’s a shame the T 3 does not help with your memory. My memory is not what it used to be but is much better than when I was on Levothyroxine. I forget names of things and people which is quite irritating to me The heart pains are much more controlled on NDT.

crimple profile image

Thanks for posting Diogenes and since the brain uses a lot of T3 it's perhaps not surprising what the research shows. Another paper to show the medics if they haven't got their eyes closed!

CeiliGal profile image

Is this linked to autoimmunity possibly?. There is a brilliant summit of 9 lectures started today online from the functional.medicine prespective explaining autoimmunity and what we need to do about it. I have hashimotos but am worried about the future and other autoimmune problems. So as well as trying to improve my current symptoms and adjust/change medication i have taken steps on the AI issues also with the autoimmune protocol. Lectures are definitely worth a look, are answering the Why and dont promote anything that i can see so hope ok to post link -

MissGrace profile image

Thank you. It’s no surprise really. It’s such a crucial hormone. It’s very sad that GPs are told to keep TSH high in the normal range for elderly hypos because of often unfounded fears about osteoporosis. This almost certainly means they will have low T3. 🤸🏿‍♀️🥛

SlowDragon profile image

Is this why DIO2 gene variation is linked too.....perhaps

Certainly I can see now, with hindsight, my mother's dementia was pre-dated by very many clear hypothyroid symptoms, classic gluten intolerance symptoms, very likely low vitamin levels....all undiagnosed to the end

bookish profile image
bookish in reply to SlowDragon

My mother, too, exactly as you say, although I also wonder about APS (Hughes' sticky blood) having led to absences, seizures & TIAs, prior to dementia. She had other diagnosed autoimmune conditions but no-one picked up on thyroid or gluten issues.

jgelliss profile image
jgelliss in reply to SlowDragon

That is such a Shame and so very Cruel . I often think to myself too in my Dear Fathers case having had heart disease and consequently developing diabetes . Had they checked his thyroid values and treated him properly with thyroid meds I have no Doubt he would have not had to suffer his ailments .

JANJAN2 profile image

This is what was wrong I think, with my late Father who had 'profound hypothyroidism' diagnosed when he was an old man.I have posted about this before:he was given T3 on his death bed, but it was too late.He behaved as if he had Alzheimer's.

I have just taken the D102 test, because I am on Armour (which has just been stopped on the NHS of course) and if I have the faulty gene, I will know for sure that Dad had it too.My life before Armour is a haze, because I have forgotten so much! Now on Armour, I am able to study Open University courses-studying before was impossible for me for years. This is very important research Diogenes and Dr Skinner saw the connection too.

TSH110 profile image
TSH110 in reply to JANJAN2

It is insanity to take NDT off the NHS prescriptions and the fiasco with T3. The whole thing is a complete nonsense but it is our lives they are messing up with their idiotic, illogical practice. Fancy increasing someone’s chances of getting Alzheimer’s or heart disease it is nothing short of criminal. Are they answerable to anyone?

JANJAN2 profile image
JANJAN2 in reply to TSH110

It is completely crazy and all about money!

LindaC profile image
LindaC in reply to TSH110

Sadly, albeit £$ is a huge factor, there are certain endos who are determined to run both T3 and any derivative out of town... to prove some little fanciful 'pet theory' they 'believe in'. It is both barbaric and 'criminal'. Dr Skinner, with his World Thyroid Register talked about taking legal action...

TSH110 profile image
TSH110 in reply to LindaC

I hope legal action is taken against them - they would be found both wanting and guilty.

LindaC profile image
LindaC in reply to TSH110

Sadly, Dr Skinner was hounded... before this could happen and many others are too afraid to challenge the very same vociferous bunch :-(

TSH110 profile image
TSH110 in reply to LindaC

They are bunch of underperforming, jealous bullies, as far as I’m concerned. It is a shame they cannot be properly challenged because they hide behind the corrupt structures that keep types like this unscruitinised in positions of power.

LindaC profile image
LindaC in reply to TSH110

It is shameful and one day will go down as one of the worst medical scandals... oh, what about CFS/ME, etc, etc?

Gcart profile image

I have 3 faulty genes to do with response to TSH . As I understand it doesnt respond very well. Sowhat the T4and T3 was doing prior to TT I will never know . Only ever TSH tested . Now supplymenting T3, can at least follow a story line on TV and read a book .

Mum before me I am convinced had same problem.

Totally believe the roll of T 3 and the brain !!

What I want is quality of life not necessarily longevity which seems to be misunderstood by medics !

TSH110 profile image
TSH110 in reply to Gcart

Your thyroid made more T3 to compensate when it worked. I’m with you on a brief life well lived not a long one that is utter pants.

Musicmonkey profile image
Musicmonkey in reply to TSH110

Not really understanding this. Surely if you have a faulty gene passed down from one or both of your parents, you have always had it? It affects conversion of T4 to T3, so it's probable that your naturally produced T4 didn't convert sufficient T3...?

Gcart profile image
Gcart in reply to Musicmonkey

Yes u are correct . I am better now taking T4and T3.

I feel better than before TT . Had so many problems,health wise , that are easier now .

Never anything thyroid checked , just TSH .

Then ultrasound because of lump show cancer 😳.

My life could have been much easier I think , but just have to get on with it now.

TSH110 profile image
TSH110 in reply to Musicmonkey

But your thyroid makes T4 and T3 so it can make more T3 to compensate for the lower conversion rate - that is when it worked properly. The body is a clever thing and often has safety systems built in. I hope that makes sense. I only have the reduced conversion polymorph and some thyroid resistance ones. I used to feel pretty well before my thyroid started failing. I don’t think it has been greatly studied as yet so more things should come to light about the DIO2 mutation and its affects.

Gcart profile image
Gcart in reply to TSH110

But what if mine wasnt working well due to both lobes with carcinoma . All I know is I have better quality of life now .

I will never know just how much hormone was being produced prior to TT .

I assume TSh wasnt rising and 'knocking ' on the door to make my thyroid respond .

So I dont think the body can always compensate when lots of things go wrong at same time 🙂

TSH110 profile image
TSH110 in reply to Gcart

I think it only compensates successfully when it is healthy, but who knows how it is affected if it is cancerous or being attacked by antibodies. A close relative had thyroid lymphoma but it was still functioning perfectly and they felt absolutely fine. It was pretty bad boiled egg sized tumours some in chest cavity necessitating a TT. No problems on Levothyroxine either - unlikely to have the DIO2 like me. C 20 years on they still feel fine.

jgelliss profile image

Diogenes Thank You so much for another Great and Extremely Important Information . Whatever is good for the brain is also very important for the heart and all the other organs . Dr's ought to be more vigilant with their patients with FT4 FT3 but especially patients that present even the slightest signs for* Alzheimer's* *Heart Disease* etc.

It's mind boggling that Medical Academia is still complacent knowingly all the information that is available to them and well documented with the importance of thyroid meds *Especially T3's *.

And this is what we are up against and depend on for our well -being ???

PiggySue profile image

Thanks Diogenes.

It makes complete sense, and I concur with most of the other posters, I was worried about early onset, until I started on T3.

jgelliss profile image

I understand that FT3 values and cellular symptoms are the most important for us . I'm just wondering if one is a great T4 converter to T3 is that enough to get T3 they need ? Or one must dose directly with T3 dose ?

AmandaK profile image

My Mum developed early onset Alzheimer's in her late 50s/early 60s and also displayed hypothyroid symptoms but was never diagnosed due to the TSH being in range, so I find this quite scary. I have a similar story in that I have never had a diagnosis of hypothyroidism (but have of ME/CFS) but am symptomatic and my FT3 levels are low in range. It's some time since the FT3 test was done, so I'll be getting tested again privately at the weekend and will post results.

On that subject, I'm wondering the best time to have the test done - last time it was mid afternoon (so logically the point when the levels of FT3 were likely to be at their lowest), despite the fact that the TSH would be lower at that particular time.

kissemiss profile image

Thank you so much for this informative link Diogenes. After twenty years on t3 only my gp + endo insist that the TSH must be in range even though the t3 is below range. From now on they decided they only need to test the TSH. Needless to say I just can't function when my t3 drops below range.

DippyDame profile image

Just a thought diogenes

"Furthermore, patients in the lowest serum FT3 quartile had a twofold increased risk of AD compared to those in the highest quartile (HR = 2.63; 95% CI: 1.06–6.47)."

IMuch of this paper is above my old and (hopefully no longer) T3 depleted brain so I'm most probably missing something here but this is bugging me!

Is it not the case that the brain is extremely hungry for T3, therefore if the T3 level is low (the result of poor conversion or whatever) then that will result in cognitive impairment.

Were that initial impairment to continue undiagnosed and without the addition of T3 that situation, would, I guess, inevitably result in a continual decline of brain function including, probably, AD as in "the lowest serum FT3 quartile".

Were any indication of low T3 to be identified at an early stage might not that impairment be overcome by the addition of T3 thus reducing the risk of AD in later life...and much misery for many!

However, I can't see the T3 nay sayers entertaining such a suggestion without a seismic shift in their current entrenched attitudes to the hormone.

It strikes me that this is another example to support the idea of having a thyroid test routinely carried out (at teenage level perhaps) as a baseline ...and possibly/hopefully before any symptoms of thyroid disorder are evident.

Oh! But I forgot......that early (diagnostic) result would most likely reduce the need for so many profit making drugs used to mask symptoms rather that cure problems They that help line the pockets of Big Pharma!

Back to T3 which we all know about!

diogenes profile image
diogenes in reply to DippyDame

It would be a good topic for a properly devised clinical trial longterm on this with T3 supplementation. The problem is it would have to be longterm and well organised for meaningful results to occur so funding would be a problem.

TSH110 profile image
TSH110 in reply to diogenes

Could we crowd fund it or would it be prohibitively expensive for that approach?

DippyDame profile image

Funding...the perennial challenge!

lady_eve profile image

I am grateful to your for posting this, on the basis that forewarned is forearmed. Thank you.

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