I have been taking Levothyroxine since the age of 40 for hypothyroidism due to an underactive thyroid gland. My medical history when diagnosed with an UAT - I was put on 100mg Levothyroxine which has been increased to 100mg/125mg alternative days over the last couple of years. Over the past year I have found that my memory is more 'foggy' than it used to be, especially remembering words and names. This week I found an article in a newspaper which stated that people with an underactive thyroid, and taking Levothyroxine as a replacement medication, were more likely to suffer with dementia and living in care homes than those who have never taken drugs for hypothyroidism. The ratio being 80% taking Levothyroxine with dementia to 20% NOT taking the Levothyroxine drug. The question is were the the people not taking Levothyroxine taking any other kind of medication, or indeed did they have a thyroid problem at all. Basically my question is 'does Levothyroxine cause dementia ,. Opinions please.
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Ricketts40
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Those are really good questions. I can't wait to read the answers.
I think one of the problems is, that newspaper articles are usually written by people who know nothing about thyroid, and don't really understand what levo is. Levo is the thyroid hormone T4. It is exactly the same as the T4 made by working thyroids. So, if the T4 made by a thyroid doesn't cause dementia, why would levo?
I'm not an expert, obviously, just thinking about it logically.
And, another problem with these articles is that they just say the patients were taking levo, as if that's all there is to it, but they don't tell you what their blood test results were. Nor if the patient his/herself considered themselves to be optimally medicated.
The brain needs a lot of T3, and if it doesn't get enough, you can have all sorts of 'brain symptoms', such as depression, anxiety, etc., including dementia. So, as I see it, it's more likely that these dementia patients taking levo were under-medicated and still slightly hypo, rather than affected by the fact that they were taking levo. That seems more logical to me.
You, yourself are only on a small dose, so perhaps you are under-medicated and that is what is causing your foggy memory. Doctors do tend to under-medicate their patients a) because they tend to dose by the TSH, which is a very bad indicator of thyroid status once it gets below 1, and b) they are terrified of over-medicating, and do not understand the implications of under-medication for their patients.
When did you last have a blood test? Did you get a print-out of the results? Do you consider yourself to be optimally medicated with levo?
Actually it is on my list of things to do today - get a copy of last thyroid test which was three weeks ago, so thank you for reminding me. When I pick up my print out I will put the results on here. You do give good advice on here GG. I am trying to avoid seeing my Dr at the moment as he wants me to take Alendronic Acid for my Osteoporosis and I have refused as would prefer to use supplements and exercise. I seem to have OP it in my right forearm but Osteopenia in the rest of my body according to my print out ??? I am right handed too. Most odd.
What supplements are you planning to take? You shouldn't really take any without testing first to check that you need them. Don't fall into the trap of thinking that you need massive amounts of calcium because that's not true. Vit D and magnesium and good levels of FT3 are the most important for good bones.
I don't blame you for not wanting to take Alendronic Acid as it has a nasty list of side-effects. And, I'm not convinced it's the best way of handling the problem. I'm also not convinced that Osteopenia is a real thing. See my profile for several articles on the subject.
I am taking 2000 of vit D, Magnesium & Zinc. I dont know what FT3 is. I am also trying to eat lots of green leaves in salads, prunes by the tin, and am off to buy some K2 & K7 if I can find some. I attend two Pilates classes a week and am doing lots of walking. I will have a look at your Profile when I return from the Dr Surgery and shopping trip as I will find that interesting. I have just read about the Green Goddess (from TV) and she reckons she was diagnosed with Osteopenia in her 50's and claims it hasn't progressed into OP since, and all she takes is calcium and Vit D and does stretching every morning, she is now 83.
You wont find any. It's Vit K2-MK7 - one supplement.
There are two main forms of vitamin K:
Vitamin K1 (phylloquinone): Found in plant foods like leafy greens.
This is the blood clotting form, the one they give newborn babies to prevent a now rare bleeding disorder called 'vitamin K deficiency bleeding' (or 'haemorrhagic disease of the newborn'.
Vitamin K2 (menaquinone): Found in animal foods (high-fat dairy products from grass-fed cows, egg yolks, as well as liver and other organ meats) and fermented foods such as natto and sauerkraut.
This is the form that directs calcium to bones and teeth and away from soft tissues and arteries
Vit K2 comes in two forms: MK4 and MK7
K2-MK4 has a short life-span., it has a half life of about 1.5 hours and needs multiple doses during the day when supplementing.
K2-MK7 has a half life of about 72 hours, so a once daily dose is enough. So it makes more sense to supplement with K2-MK7.
K2-MK7 comes in two forms. I'm not good with scientific explanations but put simply these are - All-Trans form and Cis form.
All-Trans form v Cis form:
The recommended amount of K2-MK7 is 90-100mcg for up to 10,000iu D3. The best form of K2-MK7 is the All-Trans form rather than the Cis form. The All-Trans form is the bioactive form, the Cis form is inactive (a bit like methylfolate is the bioactive form of folic acid).
There's lots of information available but mainly seems to be on sites selling supplements so I wont link to them, but the message is:
"Since trans-isomer MK-7 are more readily used by our body, they are considered more bioactive. Many K2 ingredients have a mixture of cis and trans isomers, depending on how well they are produced. You’ll want to look for K2 supplements with a high percentage of trans-isomer MK-7, ideally 100%."
The Cis form is cheaper and is what many K2-MK7 supplements use but they don't tell you this.
K2-MK7 - good brands which use the All-Trans form:
Vitabay and Vegavero are either tablets or capsules.
Vitabay also does do an oil based liquid.
Vitamaze is an oil based liquid.
With the oil based liquids the are xx amount of K2-MK7 per drop so you just take the appropriate amount of drops.
They are all imported German brands and you probably wont find them on the high street, you can find them on Amazon although they do go out of stock from time to time. I get what I can when I need to restock. If the tablet or capsule form is only in 200mcg dose at the time I take those on alternate days.
If looking for a combined D3/K2 supplement, this one has 3,000iu D3 and 50mcg K2-MK7. The K2-MK7 is the All-Trans form
But did you get your vit d tested before starting taking it?
I do hope you're not taking vit D, magnesium and zinc all at the same time, because magnesium will affect the absorption of zinc. Supplementing is quite a complicated business, actually, we have to know the rules, which is why I asked.
FT3 is the active thyroid hormone. What you are taking - levo - is T4, which is basically a storage hormone and doesn't do much until it is converted into T3. FT3 is the most important blood test result but, unfortunately, under the NHS it is rarely tested. Make of that what you will!
So, basically, it's low T3 that makes you hypo, and when T3 is low, the TSH is usually high. Which is why, with twisted logic, doctors think that the TSH is all they need to test. Which is why so many hypos continue to suffer with hypo symptoms for the rest of their lives.
And one of the things about being hypo is that low T3 usually leads to low stomach acid, so people have difficulty digesting food and absorbing nutrients. Which is why so many hypos have nutritional deficiencies and need to take supplements. But, they should get the key nutrients tested - vit D, vit B12, folate and ferritin - before starting to supplement, and supplement according to the results.
So, it doesn't really matter how good your diet is, nor what you're eating, if your stomach acid is low, you are going to have possible deficiencies, which lead to diseases like osteoporosis.
I have no idea who the Green Godess is, nor what she's doing. But, just because what she's doing is working for her, doesn't mean it will be the right thing for everyone because we're all different. It might even be dangerous for some people, like taking calcium supplements (more about that on my profile). And, as I said, there is some discussion about whether osteopenia really exists, or is it just general wear and tear on the bones which won't necessarily progress to osteoporosis - not everyone gets osteoporosis. I know plenty of 80 year-olds that don't have it - I'm 77 myself. So, be careful who you follow as an example. It might not be the right example for you.
I agree with the reply greygoose has given you regarding thyroid/dementia.
Regarding osteoporosis I was diagnosed with this 20 years ago and refused the medication. Since then I have been taking good supplements and am fine. I no longer bother with the DEXA scan whatever the result I am not taking the medication so it is pointless do the test. I do yoga x 2 and tap dance for an hour a week, walk the dog at least an hour a day and feel fine, and that's good enough for me.
They basically found that people WITH a previous hypo diagnosis, were (approx ) twice as likely to have dementia than people WITHOUT a previous hypo diagnosis . (note * some of those with a previous hypo diagnosis did not take levo , we don't know how many people , or why not taking levo )
When they looked specifically at the people WITH a previous hypo diagnosis who ALSO take levo, they were (approx) 3 times as likely to have dementia , than people WITHOUT a previous hypo diagnosis .
>65yrs + hypo diagnosis = 1.81 odds ratio to have dementia .
>65yrs + hypo diagnosis + treatment with levo= 3.17 odds ratio to have dementia .
(for ages 50-65 ~ they found no association with dementia)
the study author Dr Weng said: “One explanation for this could be that these people are more likely to experience greater symptoms from hypothyroidism where treatment was needed.”
So it's not presenting evidence that levo itself causes dementia , it's showing that hypothyroidism itself .. and in particular hypo that is bad enough to need levo, is strongly associated with incidence of dementia.
( can't access full details on how come they found so many people who had 'a diagnosis of hypothyroidism' but were not taking levo .... or why , or how crap they felt)
Thank you, tatty, that makes more sense - although, over-all, not a lot of sense. I wonder about those hypo people not taking levo, too...
But, surely we already knew all that. Every time someone tells me their aging parent has been diagnosed with dementia/Altzheimer's my first question is: have they tested thyroid and B12? Surely there's nothing new in that study, is there?
I would be more interested if they actually gave numbers: TSH, FT4, FT3. Not what the patient was taking.
the study author Dr Weng said: “One explanation for this could be that these people are more likely to experience greater symptoms from hypothyroidism where treatment was needed.”
Is it just me, or is that statement meaningless? I would think that another explanation could be that those taking levo were more than likely under-medicated.
no it's not just you . there is a lack of clear detail / meaning in both the 'abstract' of the study itself and the two (identical) news reports about it .Whole thing is clear as mud.
Without knowing how badly hypo ?.... why 'diagnosed' but not on levo ? and as you say ,,, how adequately 'treated' with levo ? etc
....it's a pretty meaningless comparison.
for the sake of argument , it could mean that lots of people who were hypo but didn't get diagnosed or take levo, simply didn't live long enough to end up in the care homes with dementia at 70 having died of 'something else' at 63 ..... leaving a disproportionate number of live hypo patients who take levo in care homes .
i suspect we will see this study trotted out by the "don't treat sub-clinical hypo in the over 50s" brigade, as 'evidence' before too long.
The article was in the Daily Mail last week. I believe it might have been in the Tuesday edition as they normally write about health articles on a Tuesday. but really not sure. The Mail is the only Paper my husband gets.
The actual article is behind a paywall but here is link to a more detailed press release.aan.com/PressRoom/Home/Pres....
Note the study was done in Taiwan.
Figures for those who are hypothyroid are strangely low. They studied 7834 people newly diagnosed with dementia and a control group of 7834 without dementia. In the dementia group 68 were hypo and in the control 34 were hypo. That's for the age group 50 and up. These numbers would then have been split into 65 plus and 50 to 64 age groups. As association between hypo and dementia was found in 65 plus age group the numbers it is based on must be very small, but we would need full article to get this info. Likewise we don't know how many were actually receiving medication.
We need the views of our statisticians what conclusions, if any, can be safely drawn from this study.
Here is another link which doesn't report detailed numbers but shows other factors associated with developing dementia.
yes ,i though that was weird too.. a total of 15,686 patients , and they only find 102 who had a diagnosis of hypo ? ~ (the 102 figure is not in the free 'abstract', must be behind the paywall) That's about 0.75% .....seems low , i wonder what the rate of hypothyroidism is in population of Taiwan ?
Also a bit concerning..... this sentence could be misinterpreted if taken out of context :
"People who took medication for hypothyroidism were three times more likely to develop dementia than those who did not take medication, the study found"
it reads like "hypo + levo" is 3 times more likely to get dementia than "hypo without levo" .....(potentially suggesting it's better not to treat hypo with levo) but that 's NOT what study found.
they found :
hypo diagnosis (including people not treated with levo) is 2 times more likely to get dementia than 'no hypo diagnosis'
hypo diagnosis(treated with levo) is 3 times more likely to get dementia than 'no hypo diagnosis'
and the study itself says "A limitation of the study was that researchers were not able to include information about how severe the hypothyroidism was for participants."
My feeling that this paper may fit diogenes category of 'misleading research' or misleading interpretation and certainly misleading reporting in the media!
"Subsequently, a number of cross-sectional studies have been performed across various geographical locations and studying various age groups. In the studies restricted to older persons, the reported prevalence of overt hypothyroidism has ranged between 0.2–5.7% and subclinical hypothyroidism between 1.5–12.5%. [9,10,11,12,13,14,15,16,17,18,19,20] Some of the main prevalence studies are outlined in Table 1. The wide variation between the various studies probably reflects the disparate nature of the populations being assessed with regards to their gender, iodine intake, age-groups, racial groups and treated thyroid disease prevalence. For example, the Zoetermeer study from the Netherlands reported the lowest prevalence of subclinical hypothyroidism of just 1.5%, most likely due to the inclusion of only men in this analysis. [19]"
When you get your thyroid bloods done, see if you can get Vit B12 and folate levels tested too. Very common for deficiencies in one or both to go hand in hand with hypothyroidism, especially if slightly undermedicated.
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