Do I need an increase?: Hi, I've just had my TSH... - Thyroid UK

Thyroid UK

137,794 members161,613 posts

Do I need an increase?

Cmoor profile image
28 Replies

Hi,

I've just had my TSH reading from doctors had bloods done on Friday afternoon at the hospital as I was there for a Neurology appointment anyway,

TSH 0.29 (0.3 - 5.6) I will get a copy of other test and update you but was wondering if this is a accurate reading ad was done in the afternoon? I feel I could do with an increase im currently on 100mg and my Acne got worse and my weight is increasing more than 3 stone in a year I also have Hashimotos, would love some advice

Many thanks

Clare x

Written by
Cmoor profile image
Cmoor
To view profiles and participate in discussions please or .
Read more about...
28 Replies
SeasideSusie profile image
SeasideSusieRemembering

Cmoor

It would be accurate for that time of day. If you need a higher TSH so that you can avoid a reduction in dose or secure an increase, then as early as possible in the morning, after an overnight fast (delay breakfast until after the blood draw) and water only, is how to have blood drawn, no later than 9am. See graph of daily rhythm of thyroid hormones here, TSH is the top one

healthunlocked.com/thyroidu...

But it's your FT4 and especially your FT3 result that will tell you if you are on enough thyroid replacement hormone.

jimh111 profile image
jimh111 in reply to SeasideSusie

There is no reason whatsoever why one should fast before a thyroid blood test. I've no idea why this is suggested. The studies show it makes no difference. Common sense tells us TSH would not rise during hunger - why increase metabolic rate during food shortage? The subjects in the referenced study had a meal at 08:30, 12:30 and 18:00. The TSH graph from this study clearly shows there is no increase in TSH after these meals were consumed. So why keep repeating the myth? It undermines our credibility.

SeasideSusie profile image
SeasideSusieRemembering in reply to jimh111

Jim

This has been mentioned many times. You are the only one who says this. Why don't you have this discussion with diogenes who has said on the forum previously that eating can lower TSH.

jimh111 profile image
jimh111 in reply to SeasideSusie

It's unfair to refer to an offhand comment in a more general post as a considered statement. Do you know of any evidence that eating raises TSH? Please look at the TSH graph in the paper you referenced. We have a duty to check the veracity of claims before we pass them on as fact. If you have no evidence or are not sure simply don't mention fasting, leave it to someone who can provide evidence. Dr Skinner never mentioned fasting before a blood test to me, indeed he and his lovely wife would offer tea and crumpets before my appointment and taking blood!

Apart from damaging the credibility of patient voices there is a danger that a new patient will believe this, mention it to a doctor and be labelled as 'FON'. Thyroid patients have enough difficulty being taken seriously without losing all credibility by making silly statements.

SeasideSusie profile image
SeasideSusieRemembering in reply to jimh111

Jimh111

You know very well who Diogenes is. You know very well that if he had no evidence or was not sure he wouldn't make such a "silly statement". What a pity I didn't bookmark the thread where he made that post.

You argue this point from time to time with members of the forum, I suppose it's my turn now. As I said, you are the only one who argues against this, there are many members who mention it. Considering who Diogenes is and what he does then his word carries more weight than yours as far as I am concerned.

As I said before, why not discuss this with him?

humanbean profile image
humanbean in reply to SeasideSusie

What a pity I didn't bookmark the thread where he made that post.

You're in luck. I did. :)

healthunlocked.com/thyroidu...

One point I saw being made in the last couple of days about fasting is that we tell people to get an early morning test done while fasting. We tell people to leave a gap between last dose of levo and the blood draw then take the missing dose of Levo immediately after the blood draw. Since thyroid meds are supposed to be taken on an empty stomach this is another good reason for fasting before a blood test.

Another point regarding fasting...

If my doctor says to me "I want to test your thyroid and your cholesterol" the non-thyroid test needs to be done fasting, first thing in the morning. There are other tests which require fasting too. So I am reluctant to do some thyroid tests fasting and some not fasting because I don't know what variability it might introduce. It may be none, but I'm not willing to experiment.

Actually I agree with jimh111 that the paper used as evidence for fasting is truly diabolical, and should be retracted. The design of it confounds food intake and the time of the blood draw so there is no way of knowing whether the TSH changes that were noted were caused by food or the time of day the test was done :

ncbi.nlm.nih.gov/pmc/articl...

But despite this I'll still fast before thyroid function tests because I always aim to keep circumstances as similar as possible from one test to another.

SeasideSusie profile image
SeasideSusieRemembering in reply to humanbean

Thank you HB. Bookmarked now :)

I'm like you, because other blood tests are often done at the same time as thyroid ones, some need fasting and my surgery fails to tell you that anyway, I fast for all my blood tests and always book them all as early as possible. As you say, like you I prefer keeping the conditions the same every time.

in reply to SeasideSusie

I also fast for all my tests as we never know if the doctor will add tests after blood is drawn. This is more common than many patients are aware of. Does anyone ever wonder why, when going for one test, the lab tech usually draws several tubes of blood (often with different colored tops?) The tech knows doctors often add tests and no one wants you to make another trip. So I want to be prepared for whatever last minute decisions the doctor may make about my tests.

jimh111 profile image
jimh111 in reply to humanbean

i'm familar with his statement 'TSH falls after eating, but FT4 not affected' but feel it is unfair to drag him into the discussion regarding what was a brief statement which I think comes from the discredited study which states 'TSH values were lowered after food when compared to fasting in a statistically significant manner in all the three groups as shown in [Table 1]. Free T4 values did not significantly alter after food in all the three groups.'. It's so unfortunate that this study was published. Peer review which is an important process but so often it amounts to 'you scratch my back' or even political censorship rather than quality control. So many good doctors can't get research published for these reasons. None of the four authors or any of the reviewers or editor noticed a fundamental error. We need better quality research in order to make progress.

SeasideSusie profile image
SeasideSusieRemembering in reply to jimh111

but feel it is unfair to drag him into the discussion regarding what was a brief statement which I think comes from the discredited study which states 'TSH values were lowered after food when compared to fasting in a statistically significant manner in all the three groups as shown in [Table 1]. Free T4 values did not significantly alter after food in all the three groups.'.

You don't know where it comes from, only Diogenes can tell you that, which would be better than you making assumptions.

CSmithLadd profile image
CSmithLadd in reply to jimh111

If you will, let's look at it this way, Jim:

For those who are afraid of receiving a faulty thyroid test result that provokes their doctor to reduce their thyroid hormone; if fasting makes them feel better... so be it!

There is plenty of ongoing debate as to whether or not fasting is necessary before doing thyroid blood tests:

"Results:

TSH was suppressed in all subjects after food irrespective of the fasting levels. Free T4 values did not change significantly. This resulted in reclassification of 15 out of 20 (75%) subjects as subclinical hypothyroidism (SCH) based on fasting values whose TSH values were otherwise within range in the postprandial sample. This may have an impact on the diagnosis and management of hypothyroidism especially where even marginal changes in TSH may be clinically relevant as in SCH and in pregnancy."

ncbi.nlm.nih.gov/pmc/articl...

We know that TSH fluctuates throughout the day. Many researchers and scientists believe that food intake has an affect on lowering TSH levels which results in doctors freaking out over low TSH and reducing thyroid hormones just as they were feeling great!

"Getting the Most Accurate Results

There are two primary factors that cause significant fluctuations in your test results; food and medication.

Fluctuations from Food

Even though common medical guidelines suggest that fasting is not a necessary element of accurate thyroid testing, many studies have shown that fasting in the morning causes TSH levels to increase as much as 26 percent.

It is common for those administering thyroid tests to indicate whether the patient was fasting or not to account for the difference in TSH levels. However, because thyroid function is unique to the individual there is still a risk of false data and inaccurate diagnosis due to food consumption prior to lab work."

holtorfmed.com/what-is-the-...

You see, there are differing opinions.

So, I must say that SeasideSusie has done nothing wrong at all. Her advice and preference is not a myth... that is uncalled for, truly. SeasideSusie merely has a differing opinion than yours. But not of mine. I am in total agreement with her. Others will have their opinions as well. This is no different than the plethora of reserach and opinions on the subject by countless specialists in endocrinology -- that have gone on for some time. We all know that some have vested interests in making results for which they are paid to find. We may be hypo but we're not fools!

The only definitive answer would be that some have an issue with eating before thyroid hormone testing and others may not. But who is to know when it might occur if they don't have an issue with it today? If clinical dosing of thyroid hormone is based erroneously on TSH (which most all conventional doctors foolishly do), then the patient who knows that must help herself anyway she can. Meaning: if fasting before testing makes her feel empowered to get the best result possible so as to not have her hormones lowered -- then it's more than worth it!

None of us need more stresses of any kind. So why not do what works for us... as individuals? The argument is on both sides. I truly believe it comes down to the individual as far as whether or not one way is better than another. If it brings stress to do it one way, then don't do it that way! My point is that it is an individual choice.

When you think about it, how can anyone truly trust what the labs tell us ("you don't have to fast before the test") when they base results on ranges that are not healthy and keep people sick and searching for answers? It's like the Cash Cow turnstile is open and ready for business... keeping sufferers dumb about their care and steadily following the Sheeple that were there before them. Do you really think their results are accurate in the first place? Not if you take into account what they're compared to! If the reference ranges were on point, none of us would have to struggle to get proper treatment.

Therefore, some of us are highly cautious and we advise others as to what we have found has the highest degree of truth -- so as to be helpful to them.

You are entitled to your opinion, Jim. I respect that.

It's an open discussion here and that's what great about HealthUnlocked: We can always agree to disagree. Done.

in reply to CSmithLadd

Very well said, CSmithLadd. When what we say or write in any area of life shows lack of respect for the other person our words often drive people to be silent or leave the situation where they are not respected. We will never know who left this forum for this reason and missed out on sorely needed information. I wanted to write a response but could not have done it as gracefully as you did.

jimh111 profile image
jimh111 in reply to CSmithLadd

CSmith, I've no problem with patients expressing opinions. A statement such as 'some of us believe we can obtain a higher TSH by fasting ...' is fine but 'overnight fast (delay breakfast until after the blood draw) and water only' is coming across as strict medical advice. Whilst a heavy fatty meal might have a transient effect on TSH a cup of tea and some toast / cereal will not make any difference, as shown in the graph that was referred to.

It's wrong to cite studies without reading them yourself, a cut + paste of text form a faulty study is no substitute for reading the paper before your quote it. If you looked at this study you will have seen that the subjects had their blood taken early morning, they were then sent away to have breakfast and a couple of hours later the second blood sample was taken. Surprise surprise the blood samples taken later in the day had a lower TSH.

Having realised their cock up this team then ran a second study ncbi.nlm.nih.gov/pmc/articl... which showed fasting made no difference. It's difficult to read but the 'Delta 1' and 'Delta 2' figures are the relevant bits.

Holtorf's blogs are full of errors and not to be trusted. It would be great if you could get him to supply evidence for his claim 'many studies have shown that fasting in the morning causes TSH levels to increase (sic) as much as 26 percent'. Should we trust someone who claims to run a 'National Academy'? As far I can see there are no professors / lecturers / students or college premises and no indication it is a National institution approved by anyone other than himself.

I will raise a separate post on the issue of fasting for TFTs when I have time. In the meantime may I request that if you mention fasting for a blood test it is made clear that this is just an opinion. In particular referrring to 'water only' creates the impression that fasting is crucial and any other tests the patient may have had without fasting will be invalid. This causes unnecessary distress and confusion.

CSmithLadd profile image
CSmithLadd in reply to jimh111

Jim,

With all due respect, you're not seeing the forest for the trees.

References to those studies were only to illustrate that there's an ever-ongoing debate on this very issue by a plethora of physicians and researchers. Whether or not you feel there is validity to those particular studies has nothing to do with the point I'm making: That I don't trust any of them. How can I?

"Wrong to cite studies?" How sweet of you to notice! The cites were not there to prove a point one way or the other except to prove there is ongoing debate about the question at hand.

It should have been clear to you that I believe any study can be skewed as proof to support whatever the agenda is of those doing the study. There are far too many variables that come into question in such studies. As if we are all the same -- and we are not. What works for one may not work for all. But still, we have to find what works for most and start there. I get it. The problem is ascertaining what works for "most." As such, we can at least start with what makes the most sense.

When someone asks me about how best to ensure the most accurate thyroid test results; my answer would be to take them at the same time of day after doing the same things you did before previous testing. That is, unless what was done was too cumbersome to recall. That's usually all it takes for a person to feel so much better when they're told to get the test early in the morning and eat breakfast afterward. Most people don't eat after midnight anyway. Since it can be difficult to replicate habits exactly -- then it makes perfect sense to me to simply limit the habits: Don't eat after midnight. Go to the early morning appt.

Easy. Habits are now easily replicated! No worries!

For most, this is their habit anyway. So they eat ten or so hours later than they did the day before? The lab doesn't say "Don't fast." The lab says "It is not required to fast." Not that it's not a better way for some or not, either. Obviously, many do fast as they are there for other tests that do require such.

Labs can't connect all the dots for every person or for any particular situation. So they use a general statement. Plus, if the concern by the patient is about gaining as accurate a measurement as possible, then why not replicate conditions that are under their control. If that makes them feel better, then great! It certainly does for me and I don't mind sharing that either.

But you say that recommending "fasting" as being something only a doctor can suggest? I take issue with that on this particular thread. You're making a mountain out of a molehill on this one. There are many, many personal experiences repeated here that help others find their way. But SeasideSusie had an excellent resource for her advice -- I certainly knew of whom she was speaking.

How we each interpret data as we see it -- is that not an opinion? Are not conclusions of study not simply "opinions" of those doing the study? Do you clarify everything you state as being your opinion? I don't think so, yet you did exactly that by calling what was an opinion of another as being "a myth," though that is only your opinion.

I think it is understood around here that we all have experiences and thus opinions. We read and digest and by trial and error we learn when we put what we've read into practice. We then share. No need to preface every word with, "In my opinion."

There is nothing in the realm of how to treat thyroid issues that cannot be somehow debated. Because what will work in one scenario will not in another, necessarily. As far as whether or not fasting will cause some undue stress to someone as they think about fasting... well, hmm. Fasting is not unusual for blood tests or procedures. It's not a Gandhi-esque fast. An early morning appointment can be handled just fine. You seemed to be reaching on that point.

I believe being consistent with regard to testing is ideal in this particular thread. Whatever that "consistency" means to the individual should make little difference to the test because it's being administered under consistent circumstances.

From a commonsense standpoint (so you don't feel compelled to unnecessarily read another study), if someone is concerned about their thyroid hormones being reduced because of thyroid testing, then whatever edge that can be used to help them feel better about it is undeniably ideal. Surely you see that is my biggest concern here.

SeasideSusie answered the original question beautifully. Is that too supposed to be qualified with, "In my opinion?"

Yes, I jest. But you get my drift.

jimh111 profile image
jimh111

Clare,

Although your TSH is a little low there's no reason why your levothyroxine can't be increased to see if it helps. You have tried liothyroxine before and it hasn't helped. It's strange that your acne is getting worse, are you in the typical age group (teens, twenties) for acne?

TSH is lower during the middle part of the day. The blood test results you have had so far will be accurate, if the blood is taken in the afternoon your TSH will be lower than if the blood is taken early morning. You can sort of make mental adjustments for this but TSH is only a rough guide so you shouldn't focus on it too much.

it would really help if you could persuade your doctor to measure TSH, fT3 and fT4 at least once. It's important to know what fT3 is doing and whether the three hormones are in step.

Cmoor profile image
Cmoor in reply to jimh111

Thank you for your response. I'm 40 so no teen acne, when I had 2 weeks of B12 injections it not long started after then I was due my 3/12 injections but refused just in case it got any worse ( my B12 is over recommended level) my weight is still increasing so went to the doctor to discuss these issues and basically said I need to come off the forums and that I need an Increase in antidepressants! which I refused, I just what to start feeling myself again having the weight gain and acne is making me more depressed so wondering whether I should up the antidepressants?

CSmithLadd profile image
CSmithLadd in reply to Cmoor

Hi there Cmoor,

It is not uncommon for hormonal imbalances to cause adult acne. That includes thyroid hormones.

Antidepressants are more likely to mask symptoms of just how hypothyroid you still are, as taking them doesn't get down to the root of the cause as to why your mood is less than ideal. It is thyroid hormone that regulates mood. Therefore it makes sense that a less-than-optimal mood can often be attributed to a lack of that which regulates mood.

Antidepressants are overused by doctors who don't understand the function of the thyroid and that inadequate blood testing doesn't reflect all that's happening in the body. If they knew, then they'd know something is off and that you're probably not getting enough thyroid hormone. They should, at the very least, do full thyroid testing to find out -- which few do. Instead, they believe limited bloodwork tells the tale. Yet the patient is suffering. It's ignorance on their part.

If you're gaining weight, antidepressants will do that as it is a very common side-effect. But not having adequate thyroid hormone will also cause weight gain as well. And definitely being ignored by your doctor will have the same effect. The mind is a terrible thing to mess about with, as our melancholy due to helplessness can attest. Our life is in their hands and there are those who routinely play with that power. Why wouldn't the patient be somewhat depressed about that alone?!

Please note that if you have been on antidepressants for any length of time, know that they must be weaned off of and not abruptly stopped. The article below may be helpful to you in that regard:

health.harvard.edu/diseases...

When you get enough of the right type of thyroid hormone for you -- as an individual -- then your body will respond in a positive manner. Meaning your most overt hypothyroid symptoms will being to wane and continue to do so as long as thyroid hormone replacement is ideal in type and quantity.

Here's another excellent resource for you to peruse. The more you educate yourself on how your body can function at its best, the more proactive you can be in your care. You are at the right place! There are many, many here who want to help you find your way to optimal health.

restartmed.com/hypothyroidi...

Healing Hugs!

Cmoor profile image
Cmoor in reply to CSmithLadd

Many thanks for your post it was very positive and what I need to hear at the moment 🙂

in reply to Cmoor

Hi Cmoor. I went through unhelpful antidepressants for years while being incorrectly treated for hypothyroidism. The problems started when I was about 39. I'm now 74 and have been on a competent helpful thyroid treatment path about 4 months. It's a slow process and I have a ways to go but am beginning to feel noticeable improvements. Though I am a retired nurse there was a lot I didn't know about effective thyroid treatment because many of my doctors over the years weren't interested enough to keep up with the information that has been available for years. There is some good advice on this forum. I'm sure you can see where many forum members have posted 'likes'. The administrators and others will help you out of the black thyroid hole many of us are climbing out of. Stay with us. There is a lot of good knowledge here. For myself, I stick with the helpful knowledge offered and avoid the critical, negative naysayers. Take care. irina

in reply to

IHi Cmoor-just wanted to add if it were me I wouldn't stop my B12 without discussing it with your doctor. No one likes acne but there are more serious problems connected with B12 deficiency. There are too many variables for you to just stop taking the B12 arbitrarily 'for several months'.. One of the most common is neurological symptoms. And though your level may be good at the moment by stopping your levels may drop too rapidly if you have an absorption problems. What other symptoms do you have? Please be careful about distinguishing advice and suggestions with medical advice. Take care.😊 irina

Cmoor profile image
Cmoor in reply to

Thank you xx

in reply to Cmoor

You're welcome.😊

Cmoor profile image
Cmoor in reply to CSmithLadd

Hi, I've just read all of the article and it's really helped -it was a great read.

What's your thought on having a little iodine? Apparently used along side selenium in small doses may be effective ( 325mcg iodine)

Many thanks

Clare

CSmithLadd profile image
CSmithLadd in reply to Cmoor

So glad to be of help to you, Clare.

Yes, I wholeheartedly believe that daily intake of iodine along with selenium is excellent for your overall health as iodine is essential for T4 production. Always take selenium along with iodine as selenium protects the body from iodine excess and facilitates thyroid hormone conversion.

You mentioned perhaps taking 325 mcg. iodine per day. I believe starting a bit lower is prudent: 225 mcg. Sea Kelp from a highly reputable nutritional manufacturer would be great as an iodine supplement. With that, take 200 mcg. selenium at the same time -- every time. I've taken that combination for nearly three years and it has worked wonders for me. It's not just the thyroid that needs iodine! The body needs it in many ways.

dailysabah.com/health/2017/...

Many doctors will still tell you that we don't have an iodine deficiency problem, yet others are discovering we do as the plethora of thyroid dysfunction issues in western civilization since the early 70s attests. Doctors are taught something forty years ago and believe everything else in life changes but the needs of their patients.

kresserinstitute.com/iodine...

Of course not all doctors think that way, but ask about a supplement or a nutrient and most of them turn whiter than the coats they wear! And they do it all the time over and over again... like they only listen when we say something that takes their breath away... like "What about Supplements? Vitamins? Nutrients?"

They are, for the most part, stuck in their old ways that were deemed protocol 70 years ago. Well, we're not the same people under the same environmental conditions as our family seven decades ago! The stresses on our bodies are endless and unrelenting. It takes it's toll -- along with dangerously low nutrient levels.

They say the same things today they said decades and decades ago even though science and our health issues have proven our needs are otherwise. Iodine is not and has never been the enemy. Take it with selenium and all will be fine. Go slowly with dosing and see how the combination works for you. I wouldn't recommend going over 225 mcg. Kelp without testing iodine levels first.

Iodine is essential to thyroid function. There were those who thought iodine was toxic to the thyroid. Learning about what is needed for optimal thyroid function will tell you that we all need iodine for good health -- and considerably more than we've been led to think.

naturalendocrinesolutions.c...

In today's world, the body is open to all sorts of heavy metals that negatively affect thyroid function. Thus we need more iodine and selenium than ever before to keep up with the fight against the abundance of environmental toxins we face each day -- in foods, soaps, cosmetics, toothpaste, carpets, clothes, hair products, etc. etc. etc.

healthandscience.eu/index.p...

Learning to steer clear of foods that hurt thyroid function (like non-fermented soy products, goitrogens that aren't fully cooked, breads and other foods that contain bromine, and gluten is not a good idea for the ideal gut health needed to restore one's overall health).

You're learning, Clare. Good for you! Keep reading about things and you'll soon fine that some things make sense and others do not. Soon you'll see the whole picture as to what you need to do to restore your health. This is just a possible start in the right direction. Everyone is a bit different, as we know. You have to find out what works for you.

Hope this is helpful to you!

Healing Hugs!!

jimh111 profile image
jimh111 in reply to Cmoor

Claire,

It looks like your B12 injections may be causing the acne as it is a reported side effect. I don't know anything about this other than what I see on a Google search and the sites that report it are vague. It's a possibility and since you have good B12 levels at the moment you can certainly go a few months without further injections to see if the acne resolves. If so, and you feel brave, you could have another injection to see if the acne returns. If you need B12 you could always switch to methylcobalamin tablets. These are as effective as injections and there's a chance they might not trigger the acne. No science behind this just a possible alternative option.

Antidepressants is a difficult topic, if you really need them you should take them. Ideally we would know the root cause of depression and address it. From a thyroid point of view depression can cause hypothyroidism (by reducing the quantity and quality of TSH) and hypothyroidism can cause depression in some patients. A difficult conumdrum. Also hypothyroidism can make antidepressant therapy 'refractive', the antidepressants stop working. In view of the above it would be really useful to know your TSH, fT3 and fT4. We could then see if the numbers are in step. Is the TSH reasonable for the corresponding fT3, fT4? Is your fT3 at a typical level for your fT4? This will give an overall view of your thyroid status, if only from a blood test point of view. I think it's essential you have these numbers, if your doctor can't or won't do it then you can run a private test for under £100 if you can afford it. Maybe your private endocrinologist has run these tests and you could ask for the results.

You have tried liothyronine before and found it didn't help. You were on a low dose of 12.5 mcg daily? It's very possible the dose was too little to be of much help so I would leave this option open for the future, after you have tried a levothyroxine dose increase. Liothyronine has been successful in resolving depression which has not responded well to antidepressants, usually in much higher doses of around 40 mcg or more. This is something to consider if simple options mentioned earlier do not work.

Do you have any signs or symptoms other than depression, weight gain and acne? (as if that's not enough!)

in reply to jimh111

Depression doesn't cause hypothyroidism; it's the other way around. Are you a physician?

jimh111 profile image
jimh111 in reply to

Irina,

It’s not good to make such a categoric statement without at least doing some rudimentary checking. As I noted hypothyroidism can cause depression and depression can cause hypothyroidism. (And there is the potential for a vicious circle).

The hypothalamus is a part of the brain that links the nervous system to the endocrine system. It secretes Thyrotropin Releasing Hormone (TRH) which stimulates the thyrotrope in the anterior pituitary to secrete TSH. The hypothalamus also secretes other hormones that regulate the pituitary. In this way the brain can influence our hormonal system in response to internal or external stimuli. For example, our hormonal responses to the sight, sound or smell of food, danger or sexual partner. The brain has considerable control over the endocrine system.

In depression or even severe stress the hypothalamus produces less TRH. This will lead to lower TSH which not only reduces thyroidal secretion of T3 and T4 but also reduces deiodinase (T4 to T3 conversion). This is called ‘low T3 syndrome’ and it is also associated with increased levels of reverse T3. This mechanism is poorly understood. A further complication is that reduced TRH also leads to the production of TSH isomers with reduced bioactivity, these isomers have the same immune response to the assay but reduced bioactivity, which can be as low as 25% of normal activity levels. This is one reason why we should not attach too much precision to a TSH result, we are measuring the presence of TSH not its activity.

Hence depression can cause hypothyroidism and in particular brain hypothyroidism which cannot be confirmed by measuring serum thyroid hormones although they might give a clue.

in reply to jimh111

Thank you for the Anatomy and Physiology tutorial. irina1975

You may also like...

Do I need an increase in Thyroxine

be asking for an increase in Thyroxine current dose 125 microgram daily My weight is approx 86kg....

Increase needed but do I increase T4 or T3?

levothyroxine. My latest results indicate that an increase in one or the other is needed....

Do I need an increased dose?

need to speak to my doc/consultant and get an increase in the daily amount of levo i take? Would...

Do I need a dose increase?

Hi, I had a blood test done on Friday as I have not been feeling too good: I’ve been gaining a bit...

Do I need to increase my NDT?

NDT about 1.5years for hashi's) I just had bloods checked and TSH 0.38 (0.2-4.5) and FT4 12...