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Hypothyroidism: The facts, the controversies, and the pseudoscience

As glands go, we don’t give the butterfly-shaped thyroid that straddles our trachea too much  thought — until it stops working properly. The thyroid is a bit like your home’s thermostat: turn it high, and you’re hyperthyroid: heat intolerant, a high heart rate, and maybe some diarrhea. Turn it down, and you’re hypothyroid: cold, tired, constipated, and possibly even depressed. Both conditions are associated with a long list of more serious health consequences. Between the two however, hypothyroidism is far more prevalent. The mainstay drug that treats it, levothyroxine (Synthroid), is one of the most prescribed in the world.

One of my more memorable pharmacy experiences involved levothyroxine. The store had recently changed its prescription labelling standards: It switched from listing the brand name, to only including the generic name (with the manufacturer in parentheses). Few patients noticed. But one elderly patient, taking Synthroid, was furious, and accused me of making a dispensing error. I assured her that levothyroxine was the active ingredient in Synthroid, and she was getting the exact same product as her last visit — but she would have none of it. Her symptoms had worsened, she said, because the medication wasn’t the same. “I want Synthroid — this levothyroxine stuff does not work,” she screamed at me across the counter. No amount of reassurance would satisfy her — I think we eventually resorted to custom, typewritten labels.

I mention this anecdote not to dismiss the symptoms of hypothyroidism as sensitive to placebo effects — hypothyroidism is a real condition with objective monitoring criteria. But this episode was one of my earliest lessons in understanding how perceptions  can shape expectations of effectiveness — something that I’ll come back to, when we look at the controversies of this common condition. Any the treatment of hypothyroidism is not without its controversies – most of which occur outside the realm of medicine, and can more accurately be labelled pseudoscience.

Hypothyroidism is the consequence of the thyroid gland failing to produce enough thyroid hormone. The body produces two thyroid hormones: thyroxine (T4) and liothyronine (T3). Primary hypothyroidism is the result of insufficient production of T4 by the thyroid gland. (Secondary hypothyroidism is a consequence of pituitary or hypothylamic disorder.) The overwhelming majority of cases of hypothyroidism are primary, and the major cause of primary hypothyroidism is autoimmune thyroid disease (Hashimoto thyroiditis). Iodine deficiency can cause primary hypothyroidism too, but it’s rare in developed countries. There are other causes of hypothyroidism, including drug therapies. But to keep this post to a reasonable length, I’ll restrict my focus to primary hypothyroidism, which seems to attract the most treatment controversy.

The prevalence of hypothyroidism varies with gender, age, the population surveyed, and the definition of hypothyroidism used. A recently completed large survey suggested an overall prevalence in America at 3.7% — presumably this will be similar in other countries where iodine deficiency is equally rare. Hypothyroidism is much more common in women compared to men., and increased in prevalence with age.

The presentation of hypothyroidism varies based on severity, from no symptoms at all, to severe cases with coma and organ failure. Patients with untreated primary hypothyroidism may describe weight gain, cold intolerance, dry skin/hair, constipation and hair loss.  While the assessment and treatment of hypothyroidism is based around patient-relevant symptoms, the diagnosis of hypothyroidism must be based on lab tests, owing to the non-specific nature of the symptoms. Three laboratory measurements evaluate thyroid function and are used to diagnose hypothyroidism:

  • Thyroid Stimulating Hormone (TSH), secreted by the pituitary, is the primary screening measure in most situations. The normal range is usually reported to be 0.3-5.5 mIU/L, and a diagnosis of hypothyroidism is likely when the TSH is elevated above 10. The less functional the thyroid, the higher the TSH. (Values will vary for what is a “normal” TSH depending on the lab.)
  • Free T4 (FT4) is evaluated when the TSH is abnormal. The usual range is 9-19 pmol/L and will be reduced in hypothroidism.
  • Free T3 (FT3) has a usual range of 2.6-5.7 pmol/L. It may be reduced in hypothyroidism, but its value is not useful for diagnosis.

The Treatments

The standard therapy for hypothyroidism is synthetic levothyroxine (LT4) alone, which supplies FT4 to the body. The body converts FT4 to FT3 as required. LT4 is effective for the vast majority of patients and is the mainstay of treatment guidelines. Many patients need to take nothing else; once their dose is determined, they take one dose a day, forever. LT4 is lifetime therapy.  Benefits of LT4 include very accurate tablet standards, stable absorbtion and steady blood levels, and good tolerability.

Liothyronine (LT3) (Cytomel) is uncommonly used for thyroid dysfunction. The active form of thyroid, administration can cause wide fluctuations in FT3 levels, increasing the risk of cardiovascular harms compared with LT4.  If LT4 is like gradually turning up your home’s thermostat, LT3 is akin to big fire in the fireplace – it can work quickly, but it’s difficult to maintain a consistent effect.  With a less desirable risk/benefit profile, LT3 is generally used only in patients intolerant to LT4, or in those who are unable to successfully achieve treatment success and symptom resolution on LT4 alone.

Combination therapy (LT4 + LT3) occurs, but isn’t supported by good evidence, despite what you might expect from the testimonials. Trials comparing LT4 to LT4 + LT3 have shown no benefit over LT4 alone — and sometimes LT4 alone comes out on top.

Some physicians, patients and particularly alternative medicine purveyors advocate that dessicated thyroid (ground up pork thyroid) has advantages over LT4. This may be based in part on the naturalistic fallacy: the idea that using a “natural” thyroid source is better than “synthetic” levothyroxine. The evidence doesn’t support such a conclusion.  In fact, judging by the evidence with LT4 + LT3, the evidence points the other direction. Dessicated thyroid contains a mix of T4 and T3. The lack of any randomized head-to-head comparisons make any comparison difficult, and renders claims of superiority unproven. While some patients seem to prefer it to T4 alone, the unpredictable stability, and potential for batch-to-batch variation make it less attractive from a patient perspective, and consequently treatment guidelines generally advise against its use.  If combination therapy is felt to be necessary, using synthetic LT4 and LT3 together allows more precise and consistent dosing. Yet there exists a vast network of websites dedicated to locating sources of dessicated thyroid and shipping it to countries where it’s not available.

Treatment Goals and Monitoring
The assessment and treatment of hypothyroidism is based on symptoms, and is guided by laboratory monitoring.  Monitoring includes measurements of TSH and more rarely FT4, with the goal of putting both into the “normal” range. And improvement can be rapid, usually starting within a few weeks, with significant improvement as levels normalize.

The Controversies

Normal Ranges
Laboratory monitoring is a critical component of evaluating thyroid function. Redefine what’s considered “normal” and you redefine what it means to by hypothyroid. While the upper limit of “normal” TSH is generally accepted to be around 5.5 mIU/L (it will depend in part on the lab standard), lowering the upper limit will move millions from “normal’ to “subclinical hypothyroidism”. There’s a debate as to whether the upper limit of a “normal” TSH should be dropped to 2.5 mIU/L. Confounding its critics, the medical “establishment” that is criticized online doesn’t yet seem convinced that revising the definition is necessary – which would create (on paper) millions of new patients. . Perhaps it’s because there’s no clear evidence of adverse consequences for not treating TSH values in the 2.5-5mIU/L range. So narrowing the range may do little for patient outcomes. Still, this is an area of continued controversy.

Subclinical Hypothyroidism
Subclinical hypothyroidism is generally defined as a “normal” T4 and a slightly elevated TSH: That is, some laboratory signs of a thyroid dysfunction, but not sufficient enough to warrant a diagnosis. Symptoms are not always present, and can be vague and nonspecific: dry skin, constipation, depression, poor memory, etc. Subclinical hypothyroidism can only be diagnosed based on test results. The clinical significance of the condition is unclear. A recent Cochrane Review suggested that treating subclinical hypothyroidism doesn’t seem to result in meaningful differences in symptoms or quality of life, nor does it decrease cardiovascular morbidity. Given the risk/benefit perspective seems unclear, treatment decisions need to be individualized, and based on the severity of individual symptoms.

Screening
Routinely screening thyroid function in adults is controversial.  Screening may be more reasonable in higher-risk patients (advanced age, family history, those with signs/symptoms, etc.). Screening would be expected to increase the likelihood of treatment and over treatment, and consequently exposure to the potential risks (not well understood) of long-term thyroid treatment. Given the uncertainty about the benefits of treatment of subclinical hypothyroidism, screening may not be necessary in those at low risk and free of typical symptoms.

Is Measuring FT4 Enough?
Guidelines recommend routine monitoring of TSH and FT4, but not  FT3, as T3 is felt to vary too significantly to normally guide treatment (though it may be useful when LT4 therapy is initiated). The alternative approach discounts the evidence and guidelines and advocates treatment with LT3 alone, or a combination of LT4 and LT3. At the extreme, some groups advise against laboratory monitoring and suggest relying on symptoms alone. It’s the alternative approach that may have driven the continued interest in dessicated thyroid, which persists on the market despite quality control and dosing challenges.

Switching Brands and Using Generics
Some countries carry multiple brands of levothyroxine, and regulators may allow brand substitution – that is, they are deemed to be interchangeable. But even in settings where switching is permitted, health professionals generally try to keep patients on the same brand, to minimize the remote chance of any variation in effects due to formulation. (So the protestations of my customer, if not based in science, were consistent with usual pharmacy standards.) Looking at the data, however, there’s probably more variation in absorption based on food effects than any potential variation between brands. And the FDA recently tightened the quality standards for all brands, reducing the likelihood of variation between tablets or between brands. Still, taking the daily dose at the same time each day is probably equally  important to maintaining stable blood values.

The Pseudoscience

Are Lab Measures Enough? Or Even Necessary?
A popular alternative approach to thyroid treatment is body temperature measurements, which are felt to be a proxy for thyroid function. While it sound plausible and could give you the impression of “taking control” of your hypothyroidism, there’s no persuasive data to link the two. Body temperature does not accurately measure thyroid function and should not be used to guide treatment.

Over-the-Counter Supplements
There are several over-the-counter thyroid supplements on the market, some of which contain animal-sourced thyroid gland. A recent study tested these supplements: 9 of the 10 had animal hormones present, some with amounts comparable to prescription drugs. Given the questionable quality control and potential for batch-to-batch variation, OTC supplements are a potentially dangerous choice for treatment.

Beyond the glandular products, there are a host of nutritional products targeted at consumers with hypothyroidism. Some of the common ingredients include:

  • Kelp and other products that are sources of iodine; however, iodine deficiency isn’t an issue for most.
  • Dong Quai, tyrosine, pantothenic  acid (vitamin B5), ashwagandha, bladderwrack, schisandra, ginseng (Siberian and American), astragalus, rhodiola, selenium, zinc, copper and dozens of other ingredients that haven’t been demonstrated to have any meaningful effects — or to actually address the root cause of the condition.

Regulators like Health Canada don’t make it any easier: they approve multivitamins and iodine-containing supplements with “thyroid” in the name, or with recommended uses like, “Helps in the function of the thyroid gland” which, while not entirely incorrect, are misleading, given iodine or vitamin deficiency  isn’t a relevant contributor to most cases of hypothyroidism. I could label the same supplements, “Helps in the function of the index finger” and be equally accurate.

You brought this on yourself
Well, that’s what Christine Northrup suggests:

It’s no coincidence that so many more women than men have thyroid problems. Thyroid disease is related to expressing your feelings, something that until relatively recently had been societally blocked for women for thousands of years. In order to have your say—and maintain your thyroid energy—you must take a fearless inventory of every relationship in which you feel you don’t have a say. Ask yourself why you don’t. Are you a silent partner in a relationship? Does your partner make all the major decisions? Is it worth it? Did your mother have her say? In what ways are you like her?

Depending on your answers, I would urge you to skillfully and empathetically begin to say what is on your mind regarding the decisions that affect your life. Make sure that when you say what’s on your mind, you do so at the right time and remain detached from the effects. In other words, try not to force your will on others. For example, it’s okay to tell your best friend that you are worried about the character of her new boyfriend, but be aware that she may not necessarily be ready to hear your remarks. It’s not appropriate to “turn up the volume” as she’s rushing out the door to meet this new man.

OK, Dr. Northrup, I’ll try saying what’s on my mind. This advice is unadulterated magical thinking. Stop blaming women for autoimmune disorders.

It’s the Adrenals

No, hypothyroidism is not adrenal fatigue – a made-up condition without any demonstrable evidence that it actually exists. Given the “symptoms” of adrenal fatigue overlap with those of hypothyroidism, screening for hypothyroidism is an appropriate element of any workup for unexplained fatigue. The same applies to taking hydrocortisone for hypothyroidism – while there are recommendations online, there’s no good evidence to show this is either safe or effective.

A Little boost to help me lose weight
The thyroid is a convenient villain when confronting weight loss. If I can toss in a final anecdote, I had my Labrador Retriever’s thyroid function evaluated when she became sluggish and gained 20lbs over 12 months. It turns out, she actually was quite hypothyroid, and her activity level and weight responded well to levothyroxine, calorie restriction, and more exercise. In the obese, hypothyroidism is rare in the absence of other symptoms. And if there’s no hypothyroidism, manipulating thyroid hormones is inadvisable.

Making Sense of It All
While there’s a lot of dissatisfaction with thyroid treatments online, the vast majority of patients find levothyroxine to be a simple and highly effective daily therapy. There are some true controversies in the treatment of hypothyroidism, but they’re buried in vast amounts of pseudoscience and bad treatment advice. So I advise my newly diagnosed patients against complicating treatment unless it’s necessary, and to start treatment with positive expectations: Synthroid is a top dispensed drug for a reason: It works. And despite the controversies, and the outlier opinions, the medical consensus on the treatment of hypothyroidism is quite strong. That means ignoring the noise, focusing on the relevant outcomes, and taking a stepwise, science-based approach to treatment.

Other References
Desiccated thyroid vs. synthetic thyroid supplementation. Pharmacist’s Letter/Prescriber’s Letter 2008;24(10):241013.

Towards Optimal Practice. Clinical Practice Guideline Working Group. Thyroid Dysfunction.

AACE Medical Guidelines for Clinical Practice for Evaluation and Treatment of Hyperthyroidism and Hypothyroidism. 2002

 

Disclosure: Scott treats his Labrador Retriever with levothyroxine.

Posted in: Nutrition, Pharmaceuticals, Science and Medicine

Leave a Comment (49) ↓

49 thoughts on “Hypothyroidism: The facts, the controversies, and the pseudoscience

  1. inconscious says:

    I’m so glad to see someone put up a post about thyroid-related matters and related woo.

    I’m currently with a preceptor for a third-year med school rotation who CONSTANTLY harps on the thyroid. His reasoning for doing so is as follows: the way food is processed these days leads to a lot of Bromine being placed in the production process – particularly with bread products; the bromination of food leads to a sort of “competitive inhibition” of the iodonation of tyrosine as they are both halogens; in specific patients this manifests as hypothyroid symptoms; this also results in the greatest vitamin deficiency in the country – specifically to iodine. Therefore he has patients buying up iodine supplements and taking armour thyroid (the dessicated thyroid discussed above).

    Yeah – he also does acupuncture, has an allergist that does “homeopathic” allergy testing, and believe in leaky gut theory.

    Anyway, I wish someone could comment on the above bromine/iodine thing. I e-mailed the doc that taught us endocrinology during 2nd year and she gave me some wishy washy answer on things being complicated and sent me a link to some medical book. She also admonished me for suggesting a medical colleague was practicing quack medicine.

    Also, I’ve heard through upper level med student friends that levothyroxine actually is notorious for not being as consistent in terms of efficacy for reasons similar to supplements – it has inconsistent concentrations of hormone/pill – compared to name brand synthroid. Not sure about the truthitude of this though.

  2. idoubtit says:

    Thanks for this, Scott. I was diagnosed with hypothyroidism in my early 20s and have been on synthroid since. When I feel a bit “off” or fatigued, I do tend to wonder about my dosage. Hoping over to the doctor for a check is not that difficult and for a while I had blood checks for TSH levels done at least once a year. I’ve settled into a steady dose now. Since the script works so well, I never considered any other recourse. I’m glad you put up this post so I have something to point to when people I know are having these problems as well.

  3. DrRobert says:

    I love that, according to alternative medicine practitioners, ground up pork thyroid is natural, but hormones from horse urine aren’t.

  4. I want to think on the details before possibly commenting indepth, but a quick comment and question.

    The comment, a while ago I suggested that desiccated animal thyroid thyroid hormone was alternative medicine and a doctor commenting here (weing, I think) said it was not alternative, but not readily available. Not sure why the difference in takes on that issue.

    The question, how sensitive to weight changes is the levothyroxine dosage? If one gains or losses weight should they visit their doctor for TSH testing and medication adjustment, or not?

  5. Inconscious “Also, I’ve heard through upper level med student friends that levothyroxine actually is notorious for not being as consistent in terms of efficacy for reasons similar to supplements – it has inconsistent concentrations of hormone/pill – compared to name brand synthroid. Not sure about the truthitude of this though.”

    Yes, my endocrinologist told me the same thing, that I should not accept generic levothyroxine replacement for sythyroid. That they often have to test more to get levels adjusted with the generic. That was several years ago though.

    1. Scott Gavura says:

      @micheleinmichigan:
      I can understand the concern about brand switches. We’re talking about doses in micrograms, so quality and consistent manufacturing is essential. However, all levothyroxine products must meet the same manufacturing standards. So while many advise against switching between brands, if two products are evaluated to be bioequivalent, then there should be no clinically relevant differences between them. Still, few want to chance it. Keep in mind that brand name levothyroxine is already reasonably inexpensive – it’s about $80 for a year of Synthroid treatment here in Canada.

      Is dessicated thyroid “alternative medicine”? That depends in part on how you’re using the term. It’s an approved drug in some countries. However, its characteristics make it less attractive as a treatment option. And there is a lack of good evidence to support its use for the routine treatment of hypothyroidism.

  6. Janet Camp says:

    Northrup’s babble is truly astonishing. This woman is quoted constantly by the woo crowd and I’ve even seen her book in gynecologists’ offices. If I had a dollar for every time I’ve heard my woo friends go on about “adrenal exhaustion”, or “estrogen dominance”…..or for every woman I know who sends off her saliva sample to some quack lab (these are usually promoted by “alternative” pharmacies who specialize in “compounding” of “natural” hormones and other dubious concoctions. What do you think, as a pharmacist, about this kind of woo in your own profession? Is there any ethics violation in doing these unvalidated saliva tests, for example?

    The women I know who do all this stuff, think that thyroid treatment is the easy way to weight loss. They simply refuse to admit that they take in too many calories, or that their “fatigue” is the result of overweight and lack of exercise.

  7. lilady says:

    This is a great article about pseudoscience and bogus treatment for non-existent hypothyroidism.

    Approximately 4-5 years ago after my yearly complete physical and blood tests, I was told that I had a mildly elevated TSH level that didn’t warrant treatment…I had no symptoms associated with hypothyroidism and the rest of the thyroid blood panel was normal…and has remained normal with subsequent yearly blood tests. I am at “that age”…a newbie Medicare recipient…and I expect to die at a ripe old age without taking Synthroid.

    I also checked out the price of a year’s supply of Synthroid that my drug plan (Medco) pays for the drug and it is $200/per year. Medco is a huge drug plan, providing drug coverage for NYS public employees and retirees and many other State and municipal health plans, so they have big time negotiating power with drug manufacturers. Scott Gavura might want to do an article in the future about the high cost of prescribed drugs in the United States versus the cost of prescribed drugs in Canada and other countries that have national health care plans.

  8. BKsea says:

    This was really interesting as thyroid issues run in my family. One thing that bothered me in the discussion of subclinical cases is the statement:

    “A recent Cochrane Review suggested that treating subclinical hypothyroidism doesn’t seem to result in meaningful differences in symptoms or quality of life, nor does it decrease cardiovascular morbidity. Given the risk/benefit perspective seems unclear, treatment decisions need to be individualized, and based on the severity of individual symptoms.”

    This really smacks of the special pleading that you hear from alternative medicine. Yes, you can’t prove an effect, but that is because treatment decisions need to be individualized and you can’t run a trial on individualized treatments. Isn’t it likely that any individualized response is just a placebo effect? Is it better if the placebo has a physical effect on some people? Or maybe it’s worse? I really struggle with this.

  9. Harriet Hall says:

    What is your understanding of the definition of subclinical? I always thought it meant no symptoms or signs that could be detected by a history and physical, but only changes that could be detected by tests.

    1. Scott Gavura says:

      @Harriet: My understanding is patients with subclinical hypothyroidism may have non-specific symptoms that are suggestive of hypothyroidism, but the diagnosis itself is based solely on biochemical findings – a normal FT4 and an elevated TSH.

      @BKsea: Reasons for treating subclinical hypothyroidism might include:

      – Many patients with subclinical hypothyroidism will eventually meet the criteria for hypothyroidism
      – There may or may not be symptoms, and those symptoms may respond to treatment
      - Treatment may improve surrogate cardiovascular endpoints

      Reasons for not treating include:

      – Cost
      – Some patients may eventually normalize their levels without any intervention
      – Initiating treatment is a commitment to daily therapy, for life
      – No demonstrated effect on cardiovascular outcomes

      Other factors considered may include age and pregnancy status. Where the net benefits are equivocal, or unclear, it’s more challenging to rule treatment in or out, so we need to apply the evidence at hand in the context of patient-specific considerations and preferences.

  10. hyperlalia says:

    When I took endocrinology we referred to hypothalamic hypothyroidism as tertiary and pituitary as secondary. (excuse the pedanticism… depending on the scope of the term “secondary” both ways could be judged correct and your way probably makes more sense to the layman)

    Regarding Bioequivalence between different formulations of drugs (generic vs. brand name) I saw on a bus next to a second year once who told me that the quality/consistency standards were higher for brand name drugs and that there had to be 95% consistency between doses whereas between a generic and a brand name there only had to be 90%. He cited a drug rep friend of his as the source. It seems possible but I reserve my skepticism. Anybody know if there is any truth to it?

  11. Esteleth says:

    Oh, goody, the thyroid!
    I got an earful of thyroid-related quackery 5 years or so ago. This is what happened, in useful list format:
    1. At ordinary checkup, the doctor notes a nodule on my thyroid, recommends I see an endocrinologist for follow-up.
    2. Endocrinologist confirms nodule existence, does biopsy.
    3. Biopsy says cancer. Endocrinologist refers to surgeon.
    4. Surgeon performs thyroidectomy.
    5. Endocrinologist provides prescription for Synthroid, which I fill and take regularly.

    Conclusion, 5 years later: I am cancer-free and healthy. Hooray for medicine and science!

    …but to hear some people (including some family members!) say it, the fact that my T3/T4 levels were within normal ranges means that I “didn’t actually have a problem” and should have tried a special diet or herbs or some shit like that. Because, apparently, when the biopsy report said, “Stage 1, but growing fast” I should have WAITED and had to endure far more than a relative simple surgery with rapid healing followed by a single round of radioiodine therapy. In fact, after the surgery (2 months post-biopsy), the pathology report post-op said that a lymph node had to be taken, as it was being invaded. I don’t want to know what it would have said if I’d waited longer than that.

    Oh, and I had an acquaintance flip out the other day when I happily reported the result of my latest lab report: undetectable TSH. This is a GOOD thing, as of course my doctors and I don’t want my thyroid to GROW BACK, which is what would happen if I had TSH floating around.

    But OMG you need TSH to maintain a healthy thyroid! Which is true, if you HAVE a thyroid, which I DON’T.

    Sorry for the rant. I’m still steaming about that stupid.

  12. Scott says:

    Oh, and I had an acquaintance flip out the other day when I happily reported the result of my latest lab report: undetectable TSH. This is a GOOD thing, as of course my doctors and I don’t want my thyroid to GROW BACK, which is what would happen if I had TSH floating around.

    My understanding was that TSH was produced by the pituitary in response to T3/T4 levels, and undetectable TSH would therefore imply abnormally high T3/T4 and hyperthyroidism. I know that for me (hypothyroid after hyperthyroid+radioiodine) normal TSH is the goal because it corresponds with normal T3/T4. It’s never been suggested that this will produce thyroid regrowth (which on the face of it would suggest that levothyroxine treatment would not be lifelong).

    Apparently there’s something different going on between the cases, or some misunderstanding somewhere, which I would be interested to understand.

  13. DKlein says:

    http://thewholepictureofhealth.blogspot.com/2010/07/integrative-overview-of-endocrines-part_27.html

    In this evidence-based program of whole health, the science of thyroid health was demystified.

    “The Thyroid is the personal power and self expression component of Maslow’s Hierarchy. This is easily understood when we think about how our throat is “our voice” and when we speak our truth and express ourselves in the world, we own our personal power and experience self-expression. Under functioning Thyroid problems are believed in many healing circles to be caused by “not having a voice” and not expressing ourselves in the world. Physically the Thyroid is intimately connected to our Brain Cortex – and our interpretation of Self.”

    Further, “The “throat chakras” – which relates to our voice in the world and how we express our WILL in the world, is what the Thyroid represents. People who have Graves disease, where their eyes are bulging from their sockets, is the result of a hyperactive thyroid gland and appears very clearly as a forceful expression of WILL or anger. If you have ever witnessed anyone becoming intensely angry about not getting their way, you can see this eye bulging occur. ”

    Imagine having the power to cure thyroid problems by speaking up more often.

  14. Saffron says:

    I realize you lacked the space to expand on this, Scott, but surely one of the most unfortunate and damaging misconceptions in the woo sphere today is the naturopathic doctrine that throwing supplemental iodine at any thyroid problem results in optimal gland function.

    In iodine-replete North America (where it is no coincidence that Hashimoto Disease is by far the most common thyroid disorder), more iodine is exactly what patients with autoimmune hypothyroidism *don’t* need.

  15. Esteleth says:

    Scott,
    My understanding was that TSH was produced by the pituitary in response to T3/T4 levels, and undetectable TSH would therefore imply abnormally high T3/T4 and hyperthyroidism. I know that for me (hypothyroid after hyperthyroid+radioiodine) normal TSH is the goal because it corresponds with normal T3/T4. It’s never been suggested that this will produce thyroid regrowth (which on the face of it would suggest that levothyroxine treatment would not be lifelong).
    Apparently there’s something different going on between the cases, or some misunderstanding somewhere, which I would be interested to understand.
    You’ve got the science right. What you’re missing is a few facts that I elided.
    I have medically-induced slight hyperthyroidism. Like, I’m just barely over the line with regards to my T3/T4 levels. This is because my doctor wants my TSH to be wiped out so that my (cancerous, removed because it was cancerous) thyroid doesn’t grow back. TSH production is in a feedback loop with T3/T4 levels. If T3/T4 levels drop, TSH rises, which leads to thyroid growth. High T3/T4 inhibits TSH production. If my T3/T4 levels were to be at normal levels, my TSH would produce at some low basal level, which would induce some thyroid growth (probably not much – it’s unlikely to produce a full-sized and functional thyroid). Since all that’s left of my thyroid is a mass of scar tissue, inducing thyroid growth would be bad inherently (scar tissue regrows healthy tissue how?) and because my thyroid was removed for a good reason (cancer). My doctor, mindful that my cancer – though thankfully found very early – was growing rapidly, wants to keep we with zero thyroid, which requires undetectable TSH.

  16. Esteleth says:

    Bah, borked the quote tag. My reply to Scott begins with You’ve got the science right.

  17. DrRobert says:

    DKlein, as soon as I read “throat chakras” I knew that you had nothing interesting to say. Really?

  18. DKlein says:

    Dr. Robert,

    That was a quote from the director of a school that teaches (supposedly) evidence-based medicine to health care providers.

  19. ZenMonkey says:

    DKlein — ha! I misread your comment at first as well. This idea that holding in our emotions causes thyroid issues is both unbelievably insulting and hilariously funny. I guess also sad in that a healthcare practitioner can’t tell the difference between thyroid-related proptosis and an angry person. Anyone who really buys this idea needs to learn that Marty Feldman, that most sullen and repressed of actors, had Graves’ disease (autoimmune hyPERthyroidism, the opposite of Hashimoto’s).

    I was diagnosed with Graves’ disease in 2004, and I got lucky in that the online forum I chose to help educate myself was very science-based, and no one suggested I heal my chakras or whatever. One controversial topic was the normal range as you mention. Many of the patients held that given variations among labs as well as, of course, individuals, “normal” could differ widely among people and it was important to find out what your specific normal was. For example, some patients claimed that they felt much better at the very high or very low end of the usual “normal range.” Is this a valid stance?

    Also, people would describe worsening of symptoms or poor reactions to a change in a generic drug’s manufacturer not due to the active ingredient(s), but due to the fillers. This dye or that other thing appeared to have an effect on patients who were used to a particular formulation (if that’s the word I want). Now these people had much more serious cases than I did, and were far more sensitive to changes in their hormone levels, so I don’t know if they could truly tell a difference, or if there were false correlations based on coincidental symptoms changes. I guess that this wasn’t exactly the case in your example of someone who only trusted a brand name, but in a sense this could explain how generic levothyroxine really might not appear to work as well as Synthroid for someone.

    Thanks for this excellent resource. I’m sure I’ll be sharing it in the future.

  20. DKlein says:

    ZenMonkey and Dr. Robert,

    My fault for the misunderstanding. My post was poorly written and I’m new so folks wouldn’t readily know I was being facetious.

  21. Scott says:

    Many of the patients held that given variations among labs as well as, of course, individuals, “normal” could differ widely among people and it was important to find out what your specific normal was. For example, some patients claimed that they felt much better at the very high or very low end of the usual “normal range.” Is this a valid stance?
    Also, people would describe worsening of symptoms or poor reactions to a change in a generic drug’s manufacturer not due to the active ingredient(s), but due to the fillers. This dye or that other thing appeared to have an effect on patients who were used to a particular formulation (if that’s the word I want).

    For both of these effects, lack of blinding makes those evaluations fairly questionable.

  22. DrRobert says:

    DKlein – my apologies!

    Merry Christmas!

  23. nybgrus says:

    an interesting discussion… my how woo is rampant everywhere!

    I read “Dr.” Northrup’s (yes, I know she is a “real” doctor, but I can barely call her that) assessment of thyroid function to my girlfriend. She is an aerospace engineer and knows very little of biological or medical sciences. I read it to her out of context and just asked her thoughts. Her face became very puzzled and then she laughed and asked if I was reading some hundred year old text book of how medicine used to be back in the dark ages for laughs (I do often read about the history of pre-scientific medicine to remind myself how far we’ve actually come). I said, no, in fact an actual MD wrote that just recently. She scoffed and walked away, saying that was ridiculous, and was glad that she knows me so she and her family can be assured to receive proper medical care (i.e. referals to non-quacks and a good evalution of treatment modalities).

    The point is you don’t need to be an expert in the relevant fields to know that what Northrup wrote is total frakking garbage. You just need to have half a brain and be willing to engage in just a little critical thought instead of surrendering your thoughts and beliefs to whomever is plastered all over the popular media.

  24. I wanted to add a couple more things. I actually have far too much personsal experience with thyroid disease, but too little time presently to relate my concerns about the diagnostic process and perceptions about subclinical thyroid disease. So I will briefly point out this.

    David Sedaris has a dark but hilarious take on the “it’s your attitude that making you sick” theory.
    http://www.thisamericanlife.org/radio-archives/episode/415/crybabies?act=4

    “Perhaps it’s because there’s no clear evidence of adverse consequences for not treating TSH values in the 2.5-5mIU/L range. So narrowing the range may do little for patient outcomes. Still, this is an area of continued controversy.”

    One concern that I have heard is that there seems to be some evidence that even subclinical hypothyroidism can lead to problems with ovulation, fertility and pregnancy. Which I think is relevant, since thyroid disease effects more women.

    Check this http://www.medscape.com/viewarticle/553887_3

    that’s a 2006 overview article

    or search medpub for subclinical hypothyroid infertility

    for more recent articles

  25. oh sorry, my quote was from Scott’s article.

  26. Also on “subclinical”. When I was diagnosed with subclinical thyroid disease I had an history of sleep problems, fatigue and sluggishness, muscle pain and spasms, GI issues, infertility and a lump in my throat from inflamed thyroid with nodules.

    My doctor explained to me I had no symptoms of thyroid disease only the test scores and the nodules. Luckily almost all of my “not-symptoms” disappear when my synthroid is prescibed with a target of being under 3.O.

    I do not get “subclinical”. :)

  27. 3.0 TSH scores, that is.

  28. ConspicuousCarl says:

    I got a warm happy fuzzy feeling when I read the part about Scott Gavura taking his doggy in for medical care.

  29. nybgrus says:

    @michele:

    That would not be my definition of “sub-clinical” then. Sounds pretty clinical to me.

    But, in general and applied with some intellectual honesty, the point of “sub-clinical” anything is that in certain cases, even if the lab value seems “off” if you have no symptoms and there is no clear cut evidence or rationale for actually treating it, then why do it? “Normal” is just defined as that which encompasses 95% of the healthy population under a bell curve. So you may be below (or above) “normal” yet if truly “sub-clinical” then it may be “normal” for you. Boy, that was a lot of quotes. This is, of course, further compounded by the fact that defining who is “healthy” and getting enough values for a true cross section isn’t always the easiest thing in the world to do. Which is why I am always… cautious… when people say “you have a low testosterone” or a “low VitD level.” Defining the limits is tricky in and of itself.

    Obviously in some cases, like say that asthma article that was eviscerated here not too long ago, the lab value is important to treat irrespective of the patient’s subjective symptoms. But when we don’t have such a clear cut understanding – and truly no symptoms – it seems prudent to me to employ a watch and wait approach.

    But to me, at least in the description you gave, it certainly seemed you were showing symptoms and thus would not fall under the watch and wait paradigm.

  30. AlexisT says:

    This is a subject dear to my heart (and one I think I’ve mentioned on SBM before). I have mild hypothyroidism. I was diagnosed at 19. That was 1996, and it was an FP, so while I don’t know what my TSH was at the time, it must have been at least 4.5. I’ve encountered some serious woo (that doctors never treat hypo appropriately, that you should dose until your symptoms disappear–dangerous advice as you can feel just fine with a TSH of 0.05; ask me how I know! and that all sorts of problems can be laid at the feet of subclinical or mild hypo, as well as the annoying Armour issue mentioned in the post). I will say that I think that the 5.5 limit may be too high and that doctors should diagnose based on a full panel rather than simply running a TSH. When my TSH was above 4, my FT4 was too low. It can be difficult to get mild (but not subclinical) hypothyroidism diagnosed.

    The most manic doctors when it comes to TSH are reproductive endocrinology. If you’re known hypo, they run TSH every couple of months, and I believe they run a thyroid panel as standard for new patients. The minute I came in at 2.7, they knocked me up 25mcg. REs (and I’m told that mine are not atypical in this respect, and they certainly weren’t what I would consider “woo” or into alt-med; they were a university based practice) believe that even slight hypothyroidism impacts fertility. They want it below 2.5 and preferably between 0.5 and 2.

  31. AlexisT – “The most manic doctors when it comes to TSH are reproductive endocrinology. If you’re known hypo, they run TSH every couple of months, and I believe they run a thyroid panel as standard for new patients. The minute I came in at 2.7, they knocked me up 25mcg. REs (and I’m told that mine are not atypical in this respect, and they certainly weren’t what I would consider “woo” or into alt-med; they were a university based practice) believe that even slight hypothyroidism impacts fertility. They want it below 2.5 and preferably between 0.5 and 2.”

    Wow, Our RE was not that “manic.” He looked at my TSH from my doctor referral. which was “normal” (I think it was 3.5ish) and said my thyroid was good. When I brought up my family history of thyroid disease and my positive ANA (a screening test for auto-immune disease) he pointed to my normal TSH and said there was no sign of a problem. I’m not aware that they ever tested for TSH again. The second opinion RE that we consulted when we were considering IVF was of the same opinion.

    When I told my RE (based on drug packet instructions) that both the rounds of pregonal I took were followed by several days of flulike symptoms, followed by fatigue, he told me that wasn’t a side effect of pregonal…that it must have been coincidental. At the time I didn’t think to question any of that, it wasn’t until a few months later that I started to feel the lump in my throat and got the thyroid nodules diagnosed that I started to wonder if my RE’s approach to my thyriod was adequate, particularly considering that pregonal isn’t great for folks with uncontrolled thyroid levels.

    I’m not sure if the process that my RE’s followed was standard or if they were cutting corners, but I do know that they were the main provider of RE and IVF in the area at that time, so that was the standard that people in my rather large city were getting. I’m happy to hear that other RE’s are more meticulous about looking at thyroid levels.

    Although in the end, I can’t complain that our RE efforts didn’t pan out. Things couldn’t have worked out better with the adoption of our two great kids, so even if it was possibly a doctor’s mistake or possibly an error of process, it was our lucky break.

    ———–

    @ nybrgus “Obviously in some cases, like say that asthma article that was eviscerated here not too long ago, the lab value is important to treat irrespective of the patient’s subjective symptoms. But when we don’t have such a clear cut understanding – and truly no symptoms – it seems prudent to me to employ a watch and wait approach.
    But to me, at least in the description you gave, it certainly seemed you were showing symptoms and thus would not fall under the watch and wait paradigm.”

    I think that watch and wait if perfectly acceptable as long as there are no symptoms*, no health concerns associated with the test results. The problem with me was that I kept being told that my levels were normal and that my symptoms must be something else. So treatment with anti-inflammatories, physical therapy, wrist splints, anti-depressants for sleep, fatigue, “dysthymia” issues… This wasn’t just one doctor, this was several in different offices.

    On the other hand, I should have been more assertive. I should have questioned doctors more closely and been more forceful in asking for a thyroid anti-body test. So in that one tiny aspect Dr. Northrup was correct, being a pushover can lead to thyroid problems (not thyroid disease, just a delay in treatment).

    ———-

    Finally, one can’t really address thyroid misinformation without mentioning MARY SHOMON and her thyroid info site. It’s always at the top of the google thyroid search results.

  32. Whoops forgot my asterisk

    *My sister, also has thyroid disease and says the best she ever felt was when her TSH was at 10…so I’m not under the delusion that my symptoms are typical for my TSH levels

  33. stanmrak says:

    What would be useful here is a discussion of what causes hypothyroid (besides iodine deficiency) and why is it becoming so prevelant in our modern world — although there’s no profit in that. A ounce of prevention…

  34. Shamrack “What would be useful here is a discussion of what causes hypothyroid (besides iodine deficiency) and why is it becoming so prevelant in our modern world — although there’s no profit in that”

    I don’t think it requires investigation. I’m almost certain the cause of the increase in auto-immune disease is due to the increase in holiday grocery shopping on Christmas eve day.

    Can’t you literally feel the stress hormones percolating?

    ;)

  35. Harriet Hall says:

    @stanmrak,

    Is hypothyroid becoming more prevalent, or is it just being recognized more often? This article http://www.medscape.com/viewarticle/572171_4 says incidence is not rising, only prevalence, which could be explained by diagnosis an an earlier age.

    Other causes are autoimmune and congenital. An ounce of prevention would be nice, but there is no known way to prevent hypothyroidism other than to insure adequate iodine intake.

  36. Lytrigian says:

    In my case, routine blood panels showed I was developing a problem as long as 8 years ago, but it’s only been the past couple when my TSH levels became high enough where treatment was thought necessary.

    Fortunately, I’ve managed to avoid the woomeisters on the subject.

    Hard to tell if it’s making any difference, though. I still haven’t been able to start exercising again.

    @stanmrak: There is no preventing it. The most common cause of hypothyroidism, Hashimoto’s thyroiditis, is an autoimmune disease. I am unable to present the technical details, but it happens when your body starts making antibodies against its own thyroid. You can’t “prevent” it any more than you can prevent allergies.

  37. stanmrak says:

    So you can’t prevent it… really? Hypothyroidism just “happens”? And you can’t prevent allergies, either? Next you’re going to tell me that the rate of allergies is not increasing as well. SOMETHING is causing this.

  38. Harriet Hall says:

    @stanmrak,
    “So you can’t prevent it… really?…SOMETHING is causing this.”
    Obviously something is causing it, but we don’t know what, and we don’t know how to prevent it at present. That doesn’t mean we won’t eventually find a way to prevent it.

  39. Jeff says:

    What would be useful here is a discussion of what causes hypothyroid (besides iodine deficiency) and why is it becoming so prevelant in our modern world — although there’s no profit in that. A ounce of prevention….

    Perhaps iodine deficiency is indeed the problem, with perchlorate intake as a contributing factor.

  40. Stamrack, sorry about spelling your name wrong earlier. It’s true, auto-immune diseases don’t get the press that cancer and some other diseases get. If you are interested in donating to research in auto-immune prevention, you might check into Johm Hopkins Auto Immune Research Center.

    “The Center’s Purpose. The John Hopkins Autoimmune Disease Research Center offers leadership in the study and development of improved diagnosis, treatment and prevention of autoimmune diseases. Physicians and scientists interested in autoimmune diseases are located in nearly every department of the Schools of Medicine and Public Health.”

    http://autoimmune.pathology.jhmi.edu/aboutcenter.html#purpose

    I think it’s wrong to assume that no one is looking into prevention of auto-immune or allergic conditions, I have heard of a number of projects associated with just that. Just because it hasn’t been figured out yet doesn’t mean no one’s trying.

    (Although no one will listen to my Christmas eve market theory)

  41. AlexisT says:

    Michele: My experience was in the past 2 years (I just had my 2nd in September), so it may also be that REs are becoming more aggressive with this issue. I know other women who have reported a similar approach–routine thyroid panels and aggressive management. I will say that it’s a bit tricky because you can’t always predict response–I had my dosage adjusted a couple of times when a 25mcg change sent my TSH from 2.7 to 0.19.

    Stanmrak: Mild hypothyroidism often causes only vague symptoms that may be the result of any number of things. It’s not terribly obvious. You have dry skin, you’re a little tired, you have some trouble losing weight (contrary to what some people believe, thyroid issues do not generally cause huge weight gain, but you have trouble losing it). It’s easy to dismiss those symptoms, and I’m still not entirely sure how I managed to get diagnosed so early. It gets diagnosed more now because there’s so much attention and patients come in asking for a thyroid panel to be run. In some respects, the attention on thyroid has been beneficial to a condition that was often overlooked. The problem is that people just ran with it, and PCPs do sometimes sigh when patients come in demanding a thyroid panel to be run, convinced that it’s the cause of all their problems.

  42. Newcoaster says:

    @inconcious.
    Good on you for challenging your preceptor. Unfortunately, there is a percentage of qualified MD’s out there who believe in or practice woo. In my community, there’s a handful who use acupuncture, Healing Touch, Reiki and Emotional Freedom Technique, for example. I have frequent…uhm…”discussions” with them.

    As Michael Shermer writes in “Why People Believe Weird Things”, smart people can also fall into woo because they think they are smart enough not to be fooled. Whenever I preceptor med students, I make sure to talk about AltMed, and see what kind of ideas they may have, or what they have been told in Med School

    Re: “subclinical hypothyroidism”. I think of this as a lab “diagnosis” only…their TSH is elevated, but they report no symptoms. It bears monitoring only. Most often the diagnosis is suggested by either a helpful Naturopath who has seen the patient, or by some online checklist of symptoms. Of note, the same checklist of vague and non-specific symptoms can be used to support a (non) diagnosis of Adrenal Fatigue, Total Body Candidiasis, EMF Sensitivity etc. I usually point out to patients their symptoms are just as diagnostic of anxiety….but that one is usually a harder sell.

  43. stanmrak says:

    Michael Shermer thinks that smart people engage in false beliefs because they think they are smart enough not to be fooled? OH! The irony!

  44. Nescio says:

    FWIW I spent several years working in a UK NHS clinical biochemistry lab measuring thyroid hormones and assessing results. I even wrote a computer program to make an automatic diagnosis on the 95% of results that were straightforward, referring the remaining 5% or so to the consultant endocrinologist. Most of what we did was screening for hypothyroidism (the rest was testing for hyperthyroidism and monitoring treatment of hypo and hyperthyroidism), and if the results were straightforward – normal FT4 and TSH – we would report them as euthyroid and would refuse any requests for another thyroid function test for the next a year unless the clinician phoned up and made a convincing case for one (this was an NHS lab with a limited budget).

    Borderline hypothyroid cases (either low FT4 or elevated TSH) would get a thyroid antibody and a repeat thyroid function test a couple of months later. In most cases you would either see a normal thyroid antibody result and a normal repeat thyroid function test or a positive thyroid antibody and a decline in thyroid function. Only a very small minority were persistently problematic, and it was up to the endocrinologist to decide what to do, but this was a very rare situation.

    BTW we would very occasionally pick up a case of hypopituitarism through a thyroid function test. If we saw a low FT4 and a low TSH we would always do a serum cortisol just in case, as cortisol is usually low in hypopituitarism.

  45. AlexisT “Michele: My experience was in the past 2 years (I just had my 2nd in September), so it may also be that REs are becoming more aggressive with this issue. I know other women who have reported a similar approach–routine thyroid panels and aggressive management. I will say that it’s a bit tricky because you can’t always predict response–I had my dosage adjusted a couple of times when a 25mcg change sent my TSH from 2.7 to 0.19.”

    I can see a concern with getting sent into hyperthyroidism, since that can have health consequences. You can’t win for losing, Eh? :) But, overall if your more recent experience shows a trend toward more aggressive management of thyroid in RE (rather than just individual offices working differently) I’m happy.

  46. evilrobotxoxo says:

    As a psychiatrist, I thought I should comment on the psychiatric manifestations of “subclinical hypothyroidism.” T3 supplementation has been used by psychiatrists for a long time as an augmentation strategy for treatment-refractory depression, particularly in cases where the person has a borderline-high TSH, and there is data showing this can be effective. I’ve personally started several patients on T3 when they had borderline high TSH levels (e.g. above 4) where the endocrinologist said that they didn’t need it, and some of them had improvements in their depressive symptoms (but some didn’t). Of course, there are people with treatment-refractory depression with completely normal TSH and fT4 levels whose depression is alleviated by T3 supplementation (intentionally pushing their TSH into the low-normal range), so I’m not claiming that the fact that T3 can help depression means that depression is necessarily a manifestation of subclinical hypothyroidism, but it does make me suspect that this is the case in a subset of patients. I’ve also talked to a senior psychopharmacologist at my institution who says that he has had several treatment-refractory depression patients over the years who had normal TSH and fT4 levels but had depressive symptoms similar to those seen in untreated hypothyroidism, and they went on to develop frank thyroid disease several years later, and he thinks that the psychiatric manifestations were an early indicator. Of course that can all be confirmation bias, and I don’t know if there is any data backing that up.

    Finally, on the generic vs. brand name thing, FDA licensing of generics is not based on equivalent clinical effect, but on equivalent blood levels when tested in human subjects. And “equivalent” typically means plus or minus 10%. So that means that one manufacturer could make levothyroxine that’s 90% as potent as the brand-name, and another one could make theirs 110% as potent. So if you’re on generic levothyroxine, your actual dosage could change by 20% from month-to-month, even if your nominal prescribed dosage stays the same. That’s why they’re changing it to a 5% range for levothyoxine specifically. For most meds this whole 10% equivalency thing isn’t a problem, but it is also a problem for many anti-epileptic meds, which also can require very tight control over dosing to get the blood levels just right.

  47. Solandra says:

    Excellent article. I just got diagnosed this month with Hashimoto’s after seeing three different doctors and being dismissed. I have done well with weight loss over the past few years, albeit VERY slow, and wondered if something might be happening since I stalled. July I saw a doctor about a lump on my thyroid and he dismissed it and said it was “nothing to worry about”. I saw another doctor this month, and they tested for TPO antibodies and some other things and sure enough, my TGAB was 210 (supposed to be under 30) and my TPO was 1900 (should be under 60), THUS, apparently, I’m not crazy. An ultrasound revealed a hypoechoic nodule of 3.1cm and the FNA showed abnormal cells but was otherwise inconclusive. So, I guess the next step is more testing or surgery. I still need to see an Endocrinologist and get my meds and that will hopefully help me lose the rest of my weight I’ve been working on, and hopefully if I have cancer as well I will be able to get that treated, but there’s SO much woo out there on this subject that it’s difficult for a new patient to know what to do. I hope other people who suspect they may have Thyroid issues push their doctors to do the appropriate testing or find another doctor. My moms doc at Kaiser outright refused to do the tests on her, so, it’s hit or miss, but the earlier it’s detected and treated the better, I say. (Oh, and I’m a 29 year old female who is very outspoken. So maybe being a talkative bitch brought this on? ;))

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