I’ve been treated for underactive thyroid for about 12 years now. I take 125g of thyroxine daily. I’m also on HRT.
Recently, I’ve not felt great, low mood, very tired, inability to get good sleep , palpitations and massive hair loss, so I got my GP to do some blood tests. They were done at 8:50am with no thyroxine taken and B vits stopped a week beforehand.
Could you clever people tell me what you think?
Thank you.
25/11/21
Vit D2 +D3
69.5 Normal range not known
Thyroid peroxidase Ab conc
9 lU/ml
Normal range 0.34
Serum TSH
0.04 ml U/L
Normal range 0.35-4.5
Serum Free T4
21.0 Pmol/L
Range 11-24
Serum Free T3
4.0 pmol/L
Normal range
3.9-6.8
Serum Ferritin
174 ug/l
Normal range
13-150
I appreciate all your efforts and knowledge!
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sunnyday7
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Very poor conversion of T4 to T3, FT4 is 76.92% through range but FT3 is a paltry 3.45% through range.
HRT can affect absorption of Levothyroxine. Do you take them at least 4 hours apart, preferably longer?
Good conversion needs optimal nutrient levels.
Vit D: 69.5 nmol/L
Do you supplement?
The Vit D Society and Grassroots Health recommend a level of 100-150nmol/L, with a recent blog post on Grassroots Health mentioning a study which recommends over 125nmol/L. To reach the recommended level from your current level, you could supplement with 3,000-4,000iu D3 daily.
Retest after 3 months.
Once you've reached the recommended level then a maintenance dose will be needed to keep it there, which may be 2000iu daily, maybe more or less, maybe less in summer than winter, it's trial and error so it's recommended to retest once or twice a year to keep within the recommended range. This can be done with a private fingerprick blood spot test with an NHS lab which offers this test to the general public:
Doctors don't know, because they're not taught much about nutrients, but there are important cofactors needed when taking D3. You will have to buy these yourself.
D3 aids absorption of calcium from food and Vit K2-MK7 directs the calcium to bones and teeth where it is needed and away from arteries and soft tissues where it can be deposited and cause problems such as hardening of the arteries, kidney stones, etc. 90-100mcg K2-MK7 is enough for up to 10,000iu D3.
D3 and K2 are fat soluble so should be taken with the fattiest meal of the day, D3 four hours away from thyroid meds if taking D3 as tablets/capsules/softgels, no necessity if using an oral spray.
For D3 I like Doctor's Best D3 softgels, they are an oil based very small softgel which contains just two ingredients - D3 and extra virgin olive oil, a good quality, nice clean supplement which is budget friendly. Some people like BetterYou oral spray but this contains a lot of excipients and works out more expensive.
For Vit K2-MK7 I like Vitabay or Vegavero brands which contain the correct form of K2-MK7 - the "All Trans" form rather than the "Cis" form. The All Trans form is the bioactive form, a bit like methylfolate is the bioactive form of folic acid.
Magnesium helps D3 to work. We need magnesium so that the body utilises D3, it's required to convert Vit D into it's active form, and large doses of D3 can induce depletion of magnesium. So it's important we ensure we take magnesium when supplementing with D3.
Magnesium comes in different forms, check to see which would suit you best and as it's calming it's best taken in the evening, four hours away from thyroid meds if taking magnesium as tablets/capsules, no necessity if using topical forms of magnesium.
'HRT can affect absorption of Levothyroxine. Do you take them at least 4 hours apart, preferably longer?’
Are you sure they can’t be taken together as all are hormones? Perhaps it depends on the type of HRT?
I was always advised that body-identical HRT could be taken with thyroid meds as there are no fillers that will interact or absorb thyroid hormone. What can happen is SHBG protein carriers increase, which risk binding too much thyroid hormone so reducing ‘frees,’ but that happens during ongoing processes within the body and there is nothing we can do about that, hence NICE advise to just increase thyroid hormone dose.
I've never taken HRT in any form so no personal experience, only what I have read. I haven't got references to all that I've read but this is from the British Thyroid Foundation
However, women with pre-existing hypothyroidism treated with thyroxine, may require an increase in their thyroxine dose after starting HRT. Therefore it is useful for thyroid function tests to be re-checked after starting HRT.
And I have a note of this but not where I read it :
Hormones such as oestrogen and progesterone can bind to thyroid hormone and prevent absorption.
my understanding from what i've read is that taking HRT can lead to the need for an increase in thyroid hormone dose. (and stopping it can mean a reduction is needed) but that this is because of something to do with more estrogen meaning more thyroid hormone is then bound /unavailable (probably what radd said . but i never understood the process fully ) similar to what happens in pregnancy ?, allowing more thyroid hormone in total to be carried ?
i was always a bit hazy on 'how' exactly , but was pretty sure it 's increased binding rather than anything affecting absorption from the gut... so i think taking HRT can result in needing a dose change regardless of how far apart it's taken from thyroid hormone.
one time i referred to HRT/dose change in a reply , someone pointed out that it was older formulations of HRT that caused this effect, but that today's formulations were much less likely to require thyroid hormone dose changes... but i can't remember quite why....,might have been that the old ones used horse urine and the new ones don't ? or that lower doses of estrogen are contained in them nowadays ?
It's because todays HRT comes in various forms; transdermal gels, patches, pessaries, etc that avoid the liver and so reduces the risk of too much TBG that bind thyroid hormones. However, with extra oestrogen still circulating in the blood a small rise is still expected but to a much lesser extent than previous oral oestrogen HRT incurred.
But these examples aren’t stipulating thyroid hormone meds be taken 4 hours away from HRT.
They both echo what I am saying which is the raise in binding proteins that renders a small amount of thyroid hormone ‘unfree’ is a natural consequence of raising oestrogen and will happen regardless of med timings.
Unlike say calcium-binding which can be avoided by the four hour gap, these extra binding proteins remain in the blood stream all the time an oestrogen -containing-HRT is taken.
Could I ask you to explain a little bit more about ,
‘Very poor conversion of T4 to T3, FT4 is 76.92% through range but FT3 is a paltry 3.45% through range.’
I’ve got a phone call appointment with my go this week to discuss results and I’d like to address the issue that you pointed out. ( I just need to be clearer before I begin!!)
T3 is the active hormone that brings us well being. Good conversion of T4 - T3 often requires optimal iron & nutrients levels for many members as well as other cofactors such as balanced cortisol levels and managed autoimmune issues.
Therefore, working on iron/nutrient deficiencies will hopefully improve conversion and elevate T3 levels enough. SeasideSusie has given great advise re supplementing. Please note Hashi can't be eliminated without having both TPOAb & TGAb tested and raised antibodies can indirectly effect conversion abilities.
Medicating both Levothyroxine and HRT can disable a small proportion of your thyroid hormones and it may be you need a dose raise. However, this might prove difficult when GP’s are dictated to by TSH levels as yours is already low so ask him to read NICE guidelines regarding taking 'HRT with hypothyroidism'.
T4 (which is what Levo is) is a storage hormone, some of which the body converts into T3. T3 is the active hormone that every cell in our bodies need. So even though you have a good level of FT4 you're not converting into much T3 so your FT3 remains low. In a treated Hypo patient on Levo patient experience shows us that most people feel best when FT4 and FT3 are fairly well balanced in the upper part of their ranges. It's low T3 that causes symptoms. Unfortunately, because of the lack of education/understanding about thyroid in medical school, very few doctors know or understand this (and it's rare for the NHS to test FT3).
A normal thyroid produces a number of different hormones. The main hormones are called thyroxine (T4) and triiodothyronine (T3). The thyroid produces approximately 80% T4 and 20% T3. The thyroid also produces T2 and T1 in very small amounts but their role is not yet well understood. T4 is generally considered to be a pro-hormone because it is inactive and only becomes active when converted to T3. However, some researchers believe that T4 does, in fact, have a function.
T3 is an active hormone and does all the work of regulating the body’s metabolism. The tissues are unable to use T4, so an enzyme called 5′-deiodinase converts it to T3. This conversion takes place in the body’s cells and tissues, mainly in the liver . Problems with the liver can upset/affect the body’s conversion of T4 to T3 and can cause problems for the thyroid.
Some people do not convert their thyroxine adequately into the active hormone, T3. This could be due to lack of certain vitamins and minerals especially selenium. Make sure, though, that you have optimum levels of all vitamins and minerals to help your thyroid system run smoothly.
Lack of conversion can also possibly be due to a genetic polymorphism (also called a variant gene that is different to what most people have – usually a small alteration) – the DIO2 gene.
If you want to find out if you have low levels of T3 or to find out if you have the variant gene, Thyroid UK works with various private testing laboratories where you can purchase a private thyroid test.
If you do have low levels of T3, or do not resolve all of your symptoms on levothyroxine, you should discuss with your doctor the possibility of a referral to a thyroid specialist endocrinologist for a trial of liothyronine. The latest guidance from NHS England state that liothyronine can only be initiated by an endocrinologist so you will need a referral.
Can I just add the accepted conversion ratio when taking T4 - Levothyroxine only is said to be :- 1 / 3.50 - 4.50 with most people feeling at their best when they come in at around 4 or under :
So to find your conversion ratio of T4 which is inert and a storage hormone into T3 the active hormone that the body runs on, like the fuel in the car, you simply divide your T3 into your T4 and I'm getting your conversion coming in at around 5.25 ( 4 / 21 ) so quite a way out from the centre ground showing your body having trouble converting the T4 into T3.
It is too low a T3 for you that fives you the symptoms of hypothyroidism just as too high a level of T3 for you will likely give you symptoms of over medication and sometimes referred to as " hyper " which they are not, as once hypo you can't become " hyper ' in the true sense of the word.
Your ability to convert the T4 into T3 can be compromised by several factors, some easily rectified, others inevitable we need optimal vitamins and minerals, and other issues blocking your conversion could be inflammation, any physiological stress ( emotional or physical ) depression, dieting, and ageing, and maybe we need to add HRT on this list, having just read your replies.
Having just looked quickly at your posts, do you have a diagnosis of a thyroid auto immune disease as there is generally a genetic predisposition and have you been successful in finding a specialist within Devon ? I'm stuck in Cornwall and have resorted to looking after myself.
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