When the inactive T4 thyroxine reaches the liver, it must be converted to the active form T3. To achieve this the mineral Selenium is needed. Selenium is not very common in European soils and food-deficiencies are not unusual. If there is a selenium deficiency the liver converts the T4 to REVERSE T3. This is another inactive form of thyroxine. Therefore there may be plenty of thyroxine in the bloodstream but much of it may be functionally worthless.
When active T3 is released into the bloodstream it must bind to the nuclear walls of the cells to signal to go faster. To properly bind and send the signal it needs Vitamins A and D. Deficiency in Vitamin A is rare, but deficiency of Vitamin D is not. Reckless and poorly informed advice from dermatologists has caused concern among many people about the effect of Ultraviolet light on skin. Vitamin D is made from cholesterol in the skin by the action of Ultraviolet light. High factor sun-blocks and avoidance of sunshine can and will cause Vitamin D deficiency. As with many other issues moderation is the key. The takeaway message from this section is to eat a decent non-processed-food diet and experience moderate sunshine on bare skin. (Do NOT burn). Selenium can be obtained by circa 6 Brazil nuts per day.
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Johnathan
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I am sorry that you found the format unhelpful. It was my attempt to break it up into a logical sequence that can be digested one chunk at a time - pituitary - thyroid - liver - cells. It works in that order so I thought that posts in that order were logical. It is quite a story and I felt that to drop it all into one large post might make it totally indigestible for the bulk of readers.
When I first joined this site in 2012, I was admonished by a knowledgeable member for even mentioning the thyroid connection with PA/B12 def. as many people were not aware of Hashimoto's as an autoimmune disease (not surprising, as GPs don't tell you and don't treat the root cause). It's now well known that there is a huge connection between autoimmune conditions, gastric atrophy, B12 deficiency, and other essential nutrients.
HU Thyroid UK have always been open to posts and replies on B12 def. in the interest of the health of their members and exploring/spreading information. In view of common and interlinked symptoms, their admin at one point even suggested that combining the information on their site in some way would be helpful to their members.
It's not surprising then that members on this site are making these connections, as both conditions are frequently interlinked with latest research on the importance of a healthy biome.
If B12 deficiency can be causal to Hypothyroidism (which it can) I do not think that it was fair to admonish you. There IS a connection and that is just a physiological fact. There is a tendency for people to want to put medical conditions in separate boxes so that they can deal with the complexities better. Unfortunately this is not how biochemistry works. It is an intricate and quite beautiful dance of interlocking systems. There is close interrelationship between B12 deficiency and hypothyroidism.
I have recently had a very challenging conversation with a GP. I asked him how his biochemistry is. He replied "rusty". That was an understatement. I do not think that he had used it since he left medical school and had no useful grasp of what was going on. I am afraid that many of them are operating on a fixed set of dosage rules, constrained by NICE the BMA and the NHS. They have less clinical freedom than you might suppose - even if they remember their biochemistry.
I have read it all and found it very very helpful - lightbulb moment - thank you ! I agree it would have been easier to read as an article altogether - maybe someone in admin can help with this ?
Hi Jonathan, I gave Part1 the thumbs up because I could follow (just) what you were saying, & I thought if like Theseus, I kept on following the thread Id sort of find my way to a better understanding of what my B12def was doing to me or rather 'why' & what more I could do to help myself.
I'm sure in terms of P&A it was 100% accurate, that you do know what you are talking about, but somehow you seemed to lose the detail in the greater picture? I felt in the end I was just wandering around with you & going nowhere! I'm not being rude/personal, just trying to say, that although we are all desperate to help ourselves & each other (that includes you I'm sure), for the most part information has to be at a lay persons level.
Some people out there have a really good grip of science, chemistry, biology..but I would guess most of us don't (that means me)..so ,a condensed, simpler version please as I'm sure you have something important to tell us?
I assume that this site is not just for lay persons. It is all inclusive. I am aware that some readers will not want to follow all of the biochemistry. Believe me - this is a simplified version. I could go into the function of B12 in the Krebbs cycle but this would have made matters worse. You will note that I provided a takeaway summary of what is needed at each stage. If a person were to follow this without necessarily grinding through every stage it would help them without doubt.
Although biochemistry is NOT a sequential process (it has an awful tendency to branch in multiple directions) I presented the facts as a sequence of events so as to try to make it more digestible without losing content. That is also why I broke it up into 4 posts. If you can digest one post at a time it might help (that was the intent).
It gripes my guts to see so many people in trouble because the medical profession is not doing its job properly. At times they are actively standing in the way of a resolution to some serious problems that people have. B12 is not just necessary for production of TSH it is used in multiple places in the body. I could not cover these and I am aware that there are other stories to tell. This is a massively important molecule and it is a quirk of evolution that we cannot synthesize such a critical substance. But that is the way it is.
If the posts helps just one person get a grip of their condition or resolves just one puzzle as to why hypothyroidism and B12 deficiency are linked it was worth the time that I spent keying it. Meanwhile - if you have any queries about the posts please feel free to PM me and I will do my best to sort it.
A piece on Medscape re Dr Centanni's research, published 2016, reports that of those with autoimmune thyroiditis, 16 per cent have another autoimmune disease, and atrophic gastritis, the forerunner to PA, is the most common, 35 per cent of this 16 per cent group have it.
Of course those of us with AIT tend to start supplementing b12 as soon as we learn we have it, so our blood tests don't show low b12 as a problem. It must be massively underdiagnosed.
I have not a flicker of doubt that you are anything but right. If the immune system attacks the thyroid it will not work properly. Also - if it is attacking the thyroid it is liable to attack other tissues too (like the parietal cells in the stomach leading to B12 deficiency). The big question that we all want to know is why it is so badly targeting. I have opinions on this but it is beyond the remit of this site. The under-diagnosis of B12 deficiency is a public-health scandal.
I have read that the soil is now depleted of Selenium - so relying on Brazil nuts could be a little hit and miss. Also remember that both B12D sufferers and Hypo folk have very poor absorption - so nuts could be an irritant to the gut. I go for the 200 mcg of Selenium in a tablet
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