This study pubs.acs.org/doi/10.1021/ac... shows that PBDE flame retardants reduce type 2 deiodinase (DIO2) expression and activity in human brain cells. T4 enters the brain where it is converted to T3 in glial cells which then supply neurons with T3. This study shows PBDEs reduce this activity although it is likely this will ony be so in a minority of people who have high hydroxylated PBDE (OH-PBDE) levels.
Antonio Bianco is an expert on deiodinase and Heather Stapleton a leading environmental scientist. So, the study had a highly regarded team.
This is a very technical study but I've posted it as an example of how there can be localised impaired T4 to T3 which doesn't show up in blood tests and can cause brain fog. I've found taking a little simeticone ("WindEze") can eliminate the symptoms of brain fog. This is because it is a non-absorbable lipid and these substances are lipophillic and subject to recirculation in the gut. I've also found Enterosgel effective, a lot lower dose than recommended on the packet - less than one teaspoon daily. Both require a few months to gradually eliminate the toxins. Note that thyroid hormone is also lipophillic so you should not take simeticone within a few hours of your thyroid hormone tablets.
My guess / hypothesis is that disorders that reduce the rate of D2 (T4 to T3 conversion) lead to a situation where the brain sometimes doesn't have enough T3, it can't convert T4 to T3 quick enough. I say this because I find I have no brain fog when out walking or playing sports but when I try to concentrate for some time, perhaps reading I gradually struggle more and more. The longer I fight it the longer it takes to recover. This suggests my brain is running out of some resource. I believe this to be T3 because when I experimented a few times with a little more liothyronine the effect was substantially reduced. However, I don't want to take what might be too much hormone so I put up with it. This is important because studies so far have not been designed to test the ability to sustain concentration and so miss the effects of a reduced D2 rate.
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jimh111
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Hi Jim, I read your website some months ago looking for the specifics of taking simethicone, so thanks for stating them here. I've been thinking about trying it for sometime.
Thankyou for this Jim- very interesting. Another sad example of how the endocrine disrupting, immunotoxic chemical soup we are all now living in is having profound effects on our health.
Thank you jimh111. Very interesting. I would just like please more clarification on Simeticone. What does it do more than the Liothronine that many of us dose with? Thank you .
Nothing! There are environmental toxins that disrupt thyroid hormone action. They mimic T3 and so block the binding of T3 to some receptors. These toxins are eliminated by the liver into the gut but unfortunately the gut reabsorbs them. They bind to fats and since simeticone is a fat it binds these toxins. Simiticone is not absorbed by the gut so the toxins are slowly eliminated down the toilet.
I have the same problem with reading I used to be able to read even technical things quite easily and I would read voraciously. Now I find it such hard going it sends me to sleep. I can manage an article, but that’s about my limit. I also find my short term memory is very poor and I cannot hold things in my head. It has all sorts of ramifications everything is so disjointed, things have to be written down, I can’t even remember what I did yesterday, past days become an amorphous mass of sameness. I hope it doesn’t get any worse but I fear it is going downhill as I speak.
I did get some simiticone some time back when you suggested it, think I had better restock.
I now take a little under one teaspoonful of Enterosgel as it works out cheaper but WindEze is easier to take on holiday. WindEze contains simeticone which is a form of poly dimethylsiloxane which captures PBDEs link.springer.com/article/1... . Enterosgel contains 'polymethylsiloxane' - I'm not sure if this is the same as the di-methyl but it works.
I used to take three WindEze capsules daily. If I forgot my brain would get fuzzy after a day or two. I think I am an extreme example as I was severely hypothyroid with normal hormone levels as can be seen in the photographs in this page ibshypo.com/index.php/hypot... .
I suspect many more people have brain fog caused by subnormal TSH secretion resulting in reduced D2 activity, a slower rate of T4 to T3 conversion. This presents as tiredness and difficulty concentrating after reading or studying for a relatively short time e.g. 20 minutes. The brain fog from PBDEs gives a sort of mental irritation making it difficult to think from the start, I feel 'fuzzy' and can't think clearly but I'm fine if I'm out walking etc. Both are helped by a higher dose of T3 but it's not good to take too much hormone.
Also read your website and so impressed with your rationale - it all makes sense although I fear, if I ever had to defend to my Dr it would be very hard to convince them, but no news there!
Also your concerns about high T4 and links to cancer really got me thinking some time ago and I had been considering introducing some T3 into my meds for a while, having had reduced conversion for sometime. Then I had problems with gallstones following a small reduction in my Levo by my Dr (which I had protested about and long resisted, but agreed to in a moment of weakness) despite having amended my vitamin supplements, as per the advice from the admins in this fabulous forum. Fortunately my TSH also popped up to 14, so the Dr had no choice but to restore my previous higher dose of T4.
I reduced my Levo and added in some self sourced Liothyronine about 5 months ago and I'm feeling great. Not massively different from my T4 days, as I think I'm lucky to have done pretty well on 125/150mcg T4 for 24 yrs, but I noticed a significant reduction in the mucin I was carrying in my my arms; not something my Dr has ever even contemplated, let alone T3 therapy. I hadn't seen an Endo for over 23 years and given my wellness, I assumed that even a referral would be pointless. My digestion has also improved and I'm now not having any issues with gallstones.
I don't feel the need to try this PBDE at the moment, but will, if my brain fog becomes problematic.
Thank you for informing us all here, it is much appreciated.
I had gallstones, I wasn't a classic case but it was brought on by high cholesterol and stasis caused by undiagnosed hypothyroidism. I needed to have my gallbladder removed, this is a highly successful operation. Most people eventually have gallstones but they don't cause problems. It's a diseased gallbladder that is usually the problem.Gallstones are often blamed when someone has IBS. It may be you had IBS which is resolved with a little T3. If it were gallstone pain you would either get sharp acute pain as a stone passes or be rolling around on the floor in severe pain. If this is the case I would suggest having the gallbladder removed.
Your photos could be of entirely different people!
Zulewski found dry skin to be 63.8% specific to hypothyroidism. Moreover, thyroid hormone cured my dry skin.
Thick build-up of skin on my feet. A small area on both elbows hard and painful. Almost OCD-level use of hand and foot creams. A tendency to form fists with my hands to avoid feeling of dryness in my palms.
Almost entirely resolved by thyroid hormone - in my case, just levothyroxine.
And I'd had dry skin issues from childhood - though they had progressively worsened over the years.
I’ve never read the instructions! I just swallow as I didn’t see any need to chew (they are small). PBDEs are subject to intrahepatic recirculation, they are eliminated by the liver into the duodenum via the biliary tract and reabsorbed by the gut. I assume the capsule will be dissolved by the stomach so it shouldn’t matter whether they are chewed or swallowed.
Some capsules are designed to be chewed and this is why I jumped to the wrong conclusion, I didn’t pay attention.
I read everything. I have to make sure there’s no issues with OH’s meds, my mum’s too. And because both mum and I react badly to things I’m always alert to anything new. It’s just habit with me and I thought arTistapple wanted to know I thought I’d reply.
If I got them and they tasted iffy I would swallow them too.
Not sure. The study found PBDEs reduced D2 activity in brain cells so this might apply to D2 activity in other cells.There is a special issue with the brain in that PBDEs bind to TTR which is the main T4 transport protein in the CSF. My guess is this reduces the supply of thyroid hormone to the brain.
A consequence of endocrine disruption is that high hormone levels are needed to overcome the resistance. This reduces TSH which will cause reduced D2 and so tissues reliant on D2 such as the brain and skeletal muscles will be affected.
PBDEs specifically affect TRBeta2 thyroid hormone receptors (more than TRAlpha1). These are expressed in the hippocampus and so certain cognitive functions such as working memory will be affected to a greater extent. The heart has TRAlpha1 receptors and so would be less affected.
I think I've gone into too much detail. The short answer is using WindEze or Enterosgel to remove endocrine disruptors will probably have minor effects on the heart. Hypothyroidism caused by endocrine disruptors tends to a slightly different profile of symptoms compared to primary hypothyroidism.
Well skeletal muscles would also be a boon for me. Whilst heart muscles are, in anatomical terms, considered to be different from skeletal, it’s funny for me they work remarkably similarly symptom wise. And yes get the difference from primary hypothyroidism probably does effect the profile; however can any one of us be sure of our cause or causes of our thyroid picture, as that depth of investigation just never takes place? Love your brain and thank you so much for posting this mind bending info. And you say you have brain fog?
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