The Focus on Thyroid Lab Test Results is Failing Patients

The focus on thyroid lab tests results is failing patients

Feeling sick and tired but your thyroid lab test results are normal?

Written by Paul Robinson

The Way Thyroid Used to Work – 1960s & Earlier

I am sixty years of age now. When I was very young, if I ever got ill, my mother would take me to our family doctor.  We sometimes had to wait a while to see him because some patients would be in his consultation room much longer than others. He would listen to what my symptoms were and then examine me. During the whole time his attention was on what my mother was saying to him and on me, the young patient in front of him. It always felt like we had his undivided attention. It felt reassuring. I still remember this very clearly.

Our family doctor very occasionally ran some lab tests, but this was a very rare occurrence. Lab tests were less frequently used then and they took far longer to return from a laboratory.  The reader may think that this was a big negative but I actually do not. The focus back then was on symptoms of the patient; it was on clinical assessment of the possible conditions or illnesses that the patient might have. This is how doctors worked. Simply because laboratory tests were not so easy to do, the doctors worked hard on understanding the clinical presentation of the patient. The skills of doctors were honed through diagnostic work – because that was the only practical way to do it.

It is in quite stark contrast to what happens these days, when you often only have five or ten minute consultations and sometimes the doctor is spending at least half of this time looking at a computer screen and typing notes or looking things up. Rarely do you get asked a lot of other questions about your health and how you are feeling.

Thyroid diagnosis and treatment was significantly different back in the 1950s and earlier. Doctors had to look at the symptoms of the patient. They had to listen hard to what the patient was saying and they had to ask enough questions to see if the patient had other symptoms that they may not have realized that they actually had.

Doctors also had to examine the patient and look for indications of low thyroid levels:

  • The presence of myxedema (thickening of the skin).
  • Dry skin.
  • Cool or clammy hands and feet.
  • Nails that were yellowed or had ridges.
  • Dry hair.
  • Thinning of eyebrows or loss of outer eyebrow hair.
  • Delayed ankle reflexes.
  • Tender points on muscles.
  • Lower than normal body temperature.
  • Other common symptoms were also looked for.

It took time to do this properly, but diagnosis was usually very effective. It was not reliant on having some laboratory tests that fell inside or outside of a reference range.

Synthetic T4 (Synthroid, Levothyroxine) was not introduced until the 1950s. Current thyroid lab tests (TSH, and the other thyroid labs) were invented in the 1970s. Before these events, all doctors had available was good clinical judgement, based on the symptoms and signs (body temperature etc. and possibly basal metabolic rate) of the patient, and the option to use natural desiccated thyroid (NDT).

If low thyroid hormone was suspected, the patient was given a trial of the only treatment available – natural desiccated thyroid (NDT). If there were improvements in symptoms and signs, this confirmed the original diagnosis of the doctor. The NDT would be adjusted (titrated) to a higher or lower dose if needed. This titration process would continue based on the presenting symptoms and signs of the patient. This meant that the doctor would have to work with the patient and listen to what they were saying about how they were feeling in response to treatment. Some signs were also assessed like body temperature, ankle reflexes, the presence of myxedema etc.

This approach worked pretty well a lot of the time. It ought to have moved forward from there, taking advantage of modern lab testing (but not being a slave to it), and having all the other thyroid medications available.

A Bit of Background on Thyroid Hormones

In a healthy person, the thyroid gland produces thyroxine (T4) and some triiodothyronine (T3). T3 is the active thyroid hormone that does the majority of the work in the body, in order to keep our metabolism running at the right rate. T4 is relatively inactive, but is produced in far greater amounts by the thyroid gland. Researchers believe that the thyroid production of T4 and T3 is in about an 8:1 ratio. However, some of the T4 produced is also converted to T3. Incidentally, the thyroid gland is the most important organ of T4 to T3 conversion (making around 25% of the T3 we require, mostly through conversion).

All is well if the person converts T4 to T3 very effectively. This of course happens in healthy people. Unfortunately, in people with thyroid problems, the thyroid gland might not make enough T4 and T3, and conversion might also not be as good as it should be. There are other reasons for poor conversion too – certain low nutrients, genetic defects that affect the enzymes that are used in the conversion process, etc.

One of the big takeaways is that T3 thyroid hormone has to be present in a high enough level for an individual in order for them to feel well. T4 alone is not ever going to be sufficient to make someone feel well, regardless of how high it is. T4 is fundamentally a storage hormone that has only weak effects in the body compared to T3. T3 is thought to be at least 10 times as powerful as T4, and is the biologically active thyroid hormone within our cells.

It is very important to know that NDT was the only treatment available once upon a time and that this medication contains a mixture of both T4 and T3 thyroid hormones. The relative mixture might vary between brands of NDT very slightly, but is typically around about a 4:1 ratio of T4 to T3.

The Way Thyroid Changed – 1970s & Beyond

During the 1970s the shift to a lab-test-centric model began, as the TSH laboratory test became available. The TSH test simply measures the Thyroid Stimulating Hormone (TSH) produced by the pituitary gland. TSH goes higher if there isn’t enough thyroid hormone. It goes lower if there is enough. Well, that’s the theory anyway.

Other tests also became available. Free T4 (FT4) measures the level of biologically free/available T4 thyroid hormone. Free T3 (FT3) measures the free T3 thyroid hormone.

During this time synthetic T4 medication also became widely available and it became the de-facto standard thyroid hormone replacement, superseding NDT. This synthetic T4 medication had no T3 hormone in it at all. It was not a direct replacement for NDT. It did not mimic what the thyroid gland produced, and it relied on good conversion from T4 to T3.

One of the arguments against NDT at that time was that the variation in T4 and T3 content was a problem for patients and maintaining a consistent dosage. This latter argument no longer applies as modern technology now ensures a very consistent content of both T4 and T3 within each NDT brand, e.g. Armour thyroid.

Doctors were trained during this time to use the laboratory tests as a primary tool in diagnosing thyroid problems. They also began to use the tests to assess whether someone was on enough synthetic T4 medication. In this significant transition period the endocrinologists and doctors had also been convinced that synthetic T4 medication was the only type of thyroid medication that was necessary. They were told it always converted to enough T3 (a bad assumption that I will come back to).

It became obvious that it was much easier and far faster for the doctors treating thyroid patients. Synthetic T4 was a cheap drug, which only needed to be taken once a day. They could also just look at the lab test results and decide if the person appeared to be treated properly.  If the numbers were ‘in range’, the person was assumed to be on the correct dosage for them. Lab-test-centric treatment with synthetic T4 became ‘an easy sell’ to doctors, as it was all just so much easier and quicker to manage.

So began the days of fast, conveyor belt, thyroid treatment. The patients were in and out of the doctors’ offices within 10 minutes or so. They no longer had to have their main focus on the patients’ symptoms and on making them actually feel totally well again. However, we know that this approach leaves many patients under-medicated or improperly treated.

So, Where Are We Now?

Both doctors and patients are now highly focused on lab test results. In many cases, both groups (patients and doctors) are operating under the mistaken belief that by focusing mostly on trying to achieve some ‘ideal’ lab test results, that the patients will fully recover. 

Note: Lab test results are extremely valuable during the diagnosis stage, prior to a patient being given any thyroid hormone – there is no question of this. My big issue is the way in which labs are being used during thyroid hormone treatment. My concern is for the vast numbers of thyroid patients who are being left with symptoms (sometimes many severe symptoms), because they are either not on enough thyroid medication or they are on the wrong type of thyroid medication. Many of these people end up with other health issues as a result, e.g. high cholesterol, cardio-vascular issues, diabetes, etc. Some are given anti-depressants even though they may not have depression as the central issue.

What Usually Happens During Thyroid Treatment?

Most doctors use the TSH test to assess their patient’s thyroid medication dosage. The standard thyroid medication is synthetic T4. Some doctors also test Free T4 (FT4) and a few also test Free T3 (FT3). 

Most of these doctors believe that their patient is well treated on T4 medication if the patient’s TSH is in the reference range. Some prefer to see TSH low in the reference range. Most doctors get concerned if TSH is near zero.

TSH has become the de facto way of assessing the T4 medication dosage. Synthetic T4 has become the de facto treatment. 

As for patients, they too are interested in their thyroid lab test results. Many believe that once the ‘right’ levels are reached that they will be well again.

The use of synthetic T4 instead of natural desiccated thyroid and the use of the TSH test and other thyroid lab tests have radically changed thyroid treatment and how its effectiveness is assessed. These changes vastly reduced the work of the doctors and endocrinologists. The reliance on the TSH test and the use of T4 medication also virtually guaranteed that no patient would ever be over-medicated. However, it was much more likely to result in the under-medication of the patient!

Why Current Thyroid Treatment is a Broken Paradigm

  1. TSH can be totally suppressed when on thyroid treatment, i.e. near zero. This is fine and it does not mean the patient is hyperthyroid. So, keeping a patient to an in-range TSH may leave them under-medicated.
  2. TSH does not track symptom improvement. So, a doctor cannot see a change in T4 medication and a lowering of TSH and assume that the patient is doing better.
  3. FT4 does not track symptom improvement either. A higher level of FT4 does not mean that the patient will be feeling better.
  4. FT3 does track symptom improvement – but this is not the main measure that most doctors focus on.
  5. The reference ranges for FT4 and FT3 are population ranges – they are far too wide to conclude anything about whether a patient is treated properly or not. They are the size of a ‘barn door’ and of no use in assessing the correct level of treatment/dosage.
  6. RT3 may or may not be an issue, and for sure there is no ideal FT3/rT3 ratio for all patients. Just as the lab ranges are wide population ranges, people all have their own individual requirements for their labs. No ratio or reference range can be applied to all people. Very high rT3 is usually an issue but that’s about all you can say about it in isolation – symptoms and signs of the patient say more.
  7. Synthetic T4 does not work for all patients. Some patients cannot get well using T4 medication alone.
  8. Research has shown that the loss of conversion capability, and of the thyroid gland in thyroidectomy patients, causes the loss of the ability to achieve a balance of thyroid hormones and good conversion rate (homeostatic balance).
  9. We also know that the thyroid gland itself is responsible for around 25% of our T3, mostly through conversion, so tissue damage through Hashimoto’s, or through removal of the thyroid, loses a huge amount of ability to convert from T4 to T3. This can often not be compensated for with T4 alone.
  10. We also know from research that some people have genetic defects that reduce the capability to convert from T4 to T3 (DIO1 and DIO2 gene defects).
  11. We also know from an immense body of thyroid patients that many of them need different medications to get well: T4, NDT, T4/T3, or in some cases T3-Only.

So, the current paradigm of thyroid treatment is utterly broken.

The Consequences

This is the really sad aspect of all of this. Thyroid patients are being left improperly treated in many cases. They are either on the wrong medication for them or they are being left under-medicated.

Both doctors and thyroid patients are now incredibly focused on lab test results. This alone is liable to waste vast amounts of time, and not lead to a good treatment and outcome. Both thyroid patients and doctors are chasing some ‘ideal’ laboratory test results. We know from the research that it is virtually impossible to use just the lab test results to determine if someone is either on the right medication or the correct dosage of it.

The shift to this broken paradigm of lab-test-focused treatment and T4 medication has caused generations of doctors and patients to become fixated with lab test results. It has caused both doctors and patients to believe that these test results will reveal something amazing. It is sad, because the lab test-focused approach often fails.

What Ought To Happen?

The medical history of the patient and their history on thyroid treatment so far are critical. How the hypothyroidism symptoms and signs of the patient change during treatment should be the primary focus.

All the thyroid medication types need to be available as options. Synthetic T4, NDT, T4/T3 and T3-Only should all be available and if one does not help the patient get well, another should be tried.

Lab test results should only be used in a supporting role during treatment. You do need to have the lab test results. However, it is how TSH, FT3, FT4 and rT3 change in relation to each other, as symptoms change with different changes in thyroid medication that is the most important thing. Doctors should be prepared to offer a different type of thyroid medication if the patient is not improving or FT3 is not rising as TSH and FT4 adjust.

The focus should be improving how well the patient feels. Labs can only give some insight into how the choice of thyroid medication and dosing is adjusting thyroid hormone levels.

We need thyroid treatment to be patient-centric not lab-test-centric once again – like it used to be, but with all the available thyroid medications and the available lab tests to make things better. I am not suggesting we ‘throw the baby out with the bath water’.

I think we do need the best things of both periods of time:

  • We have better lab testing now.
  • We have more thyroid medications available.
  • We have research findings that are informing how to do a better job of thyroid treatment.
  • We ought to have a much better and more successful paradigm for thyroid treatment. But we do not!

Wrapping Up

Doctors and thyroid patients are too focused on chasing some ideal idea of thyroid lab test results. This has been the road to nowhere for some time and it continues to lead there.

Just focusing on lab test results, and with only synthetic T4 on offer is not what doctors or patients should be doing. Just because thyroid lab results are in range does not imply that treatment has been successful.

The advent of thyroid lab tests for TSH, FT4 and FT3 ought to have made thyroid treatment far better and easier. However, in the process of using them, they have become the main focus. Synthetic T4 medication has become the main treatment. This is where it has all gone wrong. 

The current approach has abandoned the good practices of the past and has replaced these with practices that leave many patients feeling unwell. The change in the way thyroid treatment is managed that occurred in the 1970s has been the biggest step backwards that we have ever seen with the treatment of this disease. Doctors and patients alike have been convinced that by repeating laboratory tests and changing T4 medication doses that good health will be regained. This approach is failing far too many thyroid patients.

However, we have all the necessary medication, testing and research to have far more successful thyroid treatment than we do today. I hope that there will be a change for the better at some point in the future. I hope that we can take the best of the past, the best of the present, together with recent research findings and have thyroid treatment practices that actually work for thyroid patients. It is really not that hard to achieve!

About Paul Robinson

Paul Robinson is a thyroid patient and advocate at Paul Robinson Thyroid who became ill with hypothyroidism in his late twenties. He was eventually able to recover using T3 replacement therapy. He is now sixty and has written 3 books – Recovering with T3The CT3M Handbook, and The Thyroid Patient’s Manual.

READ NEXT: Chronic Fatigue Syndrome, Hypothyroidism & T3: My Personal Battle

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About Dana Trentini

Dana Trentini founded Hypothyroid Mom October 2012 in memory of the unborn baby she lost to hypothyroidism. This is for informational purposes only and should not be considered a substitute for consulting your physician regarding medical advice pertaining to your health. Hypothyroid Mom includes affiliate links including the Amazon Services LLC Associates Program.


  1. The TSH test alone doesn’t tell you much. My daughter (an RN) had graves and her TSH test came back, just fine. She insisted on the FT 3 and FT 4 and sure enough, graves!! Now she just gets tested whenever she feels like it because we know how we feel.

    I really got tired of the doctor’s claiming I’m okay on not enough Synthroid. I finally stopped going( 2008) because I found a OTC supplement that works for me.

  2. So how do I KNOW if I am hypothyroid? If my labs are normal, how do I KNOW that the symptoms aren’t from some other disease, like a vitamin deficiency or poor sleep? To just assume and start taking different thyroid medications seems a bit nuts. I’m sure speed would make me feel better too, but that doesn’t mean I should do it. It’s all so confusing!

    • The idea is to use the blood TSH level, as well as visible clinical signs, and the patient’s report of their symptoms, as sources of evidence for diagnosis. Your TSH level won’t be high if everything’s working as it should.

      Once treatment begins, though, low TSH isn’t to be relied on as evidence that you’re well.
      Medication with Levothyroxine, synthetic T4, suits most people. However, those users who can’t break down T4 to its useable form, T3, or can’t get T3 into the cells, won’t trigger high levels of TSH, because TSH responds to what’s in the blood. It doesn’t tell us what’s going on in our brain or liver or other essential parts.

      You can have low TSH, plenty of blood T4, and still be starving.

  3. Lauren Smith says

    My thyroid was tested 3 times when I was younger. It was normal but I very much had hypothyroidism. The fact that my hypothyroidism went untreated for so many years because of unreliable test results has had major psychological effects. I will never be able to trust any tests. Also I lost 60 pounds over the past few years. My synthroid has not been lowered but my thyroid is still normal. Further proof of how unreliable the test is.

  4. Margret Stahl says

    Thank you for helping educate and inform. After reading your information I asked my Dr to retest everything. He hasn’t had my levels checked for over a year and I struggle with numerous symptoms. I feel terrible. I have never had any test except TSH and I have been taking the same T4 medication and dosage for 12 years.
    I left and took my labs to another Dr. I got the same thing. “Your numbers are normal”. I can’t get in to see the endocrinologist for 6 months. I won’t have any more hair if I have to wait that long. Why is it so hard to get help?

  5. I live in Puerto Rico and was diagnosed with thyroid cancer in 2014. Had a thyroihitemic in September 2014. Had been taking Synthroid since then upping a lowering my dosage. I feel worse everyday. Have headaches, dizziness, weakness. Endocrinologists here in PR are so busy with so many patients with thyroid problems and it is very hard to find doctors available to seek different opinions. I’ve read before about different treatments for thyroid problems but haven’t been able to find a doctor here to discuss my options for different treatment.

    • My only advice would be to call Mind Body Spirit Care in Tampa Fl. Ask them for T150. Take it like other thyroid meds (30 minutes before eating or drinking anything in the morning). I saw vast improvements with Xymogen T150 (desiccated thyroid, spleen, pancreas, etc…). My depression went away and I now have so much energy in spite of the fact I don’t work out like I should.

  6. This is so shocking! I’m italian and endocrinologists here prescribe only T4
    Thanks to this and others blogs I’ve been able to understand that I wasn’t crazy and my symptoms were real
    I fortunately live in Rome and some pharmacies supply NDT from Vatican State
    Is like going abroad for a simple medicine not available in my country
    And most shocking is that 3/4 endocrinologists in all the entire country are open minded about a different approach to hipothyroidism

  7. Claire Zippilli says

    Just had my thyroid removed after 5+ years of being tested and medicated , gained weight every year . After an accident a nodule was discovered . After a failed biopsy , could not be aspirated we opted for surgery . Upon going in there they discovered it was cancerous. No surrounding lymph nodes were cancerous . I already have dropped 7 lbs. I am now on 100 mg of synthetic thyroid meds, Os Cal with vitamin D and trying yo keep levels high to have strength . Persist in asking what is wrong , 3 drs, all told me we will continue to monitor it every 3-6 months . No way was I leaving a nodule that was over half an inch long and wreaking havoc on my chokestral , edema , weight gain, foot pain,etc. Find someone to do what you want to solve this .

  8. Sigrid Saradunn says

    I had Grave’s Disease in 1980 which was treated with radioactive iodine. I then became
    hypothyroid and have been on synthroid ever since.
    My question, as a patient, and health care professional, (RN), I am curious if the treatment doses … determined by blood work, not on how I feel (when I feel like I can get my life together, my weight is responding to my food plan appropriately, the medication is usually increased to bring the level down and then I gain wt even after adjusting the food plan to less carbs and calories. My exercise regimen is nil due to exhaustion even with plenty of sleep.
    Needed to vent… thanks for the place to do so.

  9. In 2013, there was a study at the Walter Reed Military Medical Centere by Dr. Thanh Hoang, D.O. that proved dessicated thyroid (NDT) is an effective treatment for hypothyroid. Most doctors don’t know about this study.

  10. I am extremely frustrated with my doctor. I had my TSH tested in April and it was slightly elevated, as well as my cholesterol. My doctor proscribed Synthroid, but it gave me unbearable side effects… so he took me off. Then he sent me for another blood work T4 and T4 , which came back within a normal range.
    Having said all of this, I have a lot of symptoms of hypothyroidism….. now I am left hanging.
    I don’t know what to do, as I also suffer from PTSD, Anxiety, Chronic Pain since the two MVA in 2013. Besides all of this my heart rate has been elevated for the past 6 months.
    I am going crazy now…..
    Not sure what to do.

    • Go get a second opion i also suffer from thyroid issues and sure know how u feel never feel 100 percent even with meds but they do help

  11. Angela Navarro says

    I am new to support groups… are we allowed to speak our mind about what we are going through, what we went through and how we feel about this dreadful disease?

  12. Excellent article. Glad that the author said all treatment options
    should be available, because you never know what might work
    for someone. I’ve had years of bad health because in 1982-83, they
    quit making the version of Synthroid that really helped me. The company
    wanted to be “cost-effective,” as one University thyroid professor told me–and the new version was not required to be tested for safety & effectiveness
    on anyone before being released in the marketplace. I had over
    six good years on the old version when I was a teen, but lots of trouble
    ever since despite being tried on all sorts of different thyroid drugs & doses.
    Having a little more success with NP thyroid right now, but
    it’s still a struggle. I wish drug companies couldn’t just discontinue
    making a version of a thyroid drug that was helping people. I wasn’t
    the only one affected by Synthroid’s changes ‘way back, and I still
    feel if they ever could duplicate the old version, maybe some people
    would have a better outcome with their thyroid treatment. Other
    thyroid drugs have made changes and affected some patients badly,
    too, over the years–Armours and a couple in Europe, I think. This
    kind of thing needs to stop, and if I ever get in a position to do
    something about it, I will. The author is right in that sometimes
    an older way of doing something has some real merit, whether it be
    an older version of a drug, or an older approach to treating a thyroid
    patient, which would include really looking at one’s symptoms.

  13. I can gain weight nut i have all the symptoms. My blood work is normal so what should i do

    • Elizabeth says

      Check out
      It will tell you the right way to look at labs and what labs are needed. This site has 17 years of patients experiences and wisdom.

  14. Den Demron says

    I was having horrible symptoms for over 4 years. Endo’s were the worst. NOT ONE ever asked how I was feeling. They would just read the freaking lab report and say take more or take less. I hated, absolutely HATED going to see one. The idea of having to live this way for the rest of my life was depressing as hell. Where does one gone where they don’t don’t know where to go? One day I was in a Sam’s club and I had the idea of asking one of the pharmacists behind the counter for help. As I approached the desk I thought who would have the names of doctors who prescribe NDT and or T3 more that a pharmacist? So I asked one of them for a name of a doctor that prescribes T3 or NDT? She went to the back and came out with a name of a DO GP that worked with her patients using NDT. I immediately made an appointment and saw her the next week. I was in bad shape, hopelessly tired and I could feel myself cratering. I saw her and gave her my latest labs. She looked at me and said “I don’t treat numbers, I treat people.” “How are you feeling?” She got me back on my feet and living life again. Don’t get me wrong – it’s not perfect but I am soooo much better than I was when I was seeing those Endo’s who thought they hung the moon. They couldn’t give two cares about how I was feeling – just “Take two of these a day and come back in 2 months.” Screw that. Don;t give up – go talk to a pharmacist.

  15. Melissa Fields says

    I don’t mean to be judgmental but no where on Here do I see you mention the factor of taking your medication on an empty stomach. My NP and a bottle of water is on my night stand. I take my medication every morning when my eyes open. And I wait 2 hours before consuming ANYTHING. I have suffered with thyroid since I was 15, I’m 55 now. I had a lobedeitomy.
    When I am diligent with this practice my body thanks me. I was informed by my GP (back in the 1970) to always follow this practice. Don’t get me wrong, I have systems of my Thyroid not functioning properly but for the most part those are mild.
    I’m one of the blessed ones, my Nurse Practitioner listens to my body.

  16. So are there any doctors who will treat according to symptoms? I am being treated but my endocrinologist treats me strictly by my lab results. Yet I still have many symptoms. It’s so frustrating.

    • Have had that exact same issue EXCEPT when I was treated in Portland, Oregon. Seeing another new endo soon. I hope he listens to me first, and labs second!

    • I don’t know where you’re located, but the McMinn Clinic in Birmingham, Al will greatly consider symptoms in addition to labs.

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