Top 5 Reasons Why You Shouldn’t Order Your Own Blood Tests

There is a recurring thread throughout the comments on some of my posts, with respect to people’s desire to order their own blood work. To give you an idea of the sentiment, here’s an excerpt from one such comment:

The mighty TSH test has already fallen. Taking a blood test and reporting its values to a patient and not being curious about their continued symptoms is not being a doctor. That’s just reading numbers… Patients have every right to order their own tests and investigate for ourselves. We paid doctors to do it, and they didn’t. Shame on them.

I like this comment because it is practically begging me to unpack the author’s implicit assumptions, stories she’s telling herself about her doctors’ competence and motivations, and the outright falsehoods she accepts as fact. With that preamble, let’s use her comment as inspiration to explore the reasons why patients should not be permitted to order their own labs:

1. Your Internet Research ≠ A Medical Degree

I can already sense you itching to bang out an angry response on your tiny mobile phone screen’s keypad*, but please take a breath and bear with me. There is an extraordinary amount of poor information on the web, particularly in the field of Endocrinology, in which internet quackery abounds. After tens of thousands of exam room encounters with patients, I can confidently state that it doesn’t matter how intelligent you are – you can still be bamboozled by alt med charlatans and you can still be generally stupid about your healthcare. You need someone to guide you through the cacophony of crazy that inhabits the internet.

The argument some of my readers make against this is: “My doctor is an idiot/incompetent/disinterested/condescending/callous, so I need to take my health into my own hands.” While I sympathize with people in this situation, you must realize that having a crappy doctor (or perceiving that you do) does not make you any more qualified to be your own doctor. You continue to be subject to all the same limitations, regardless.

Judging by the comments I receive on Hormones Demystified, my readership is overwhelmingly comprised of smart people. But even some of these sharp folks espouse internet falsehoods like they’ve been passed down on stone tablets by Moses himself. Look, I don’t blame you for believing some of the plausible-sounding medical advice that’s promulgated by alt med – it can appear incredibly reasonable and compelling. I would suggest, however, that you find a competent medical professional who can help you separate fact from quackery. Even if you are reading unimpeachable sources, you will need a doctor to help you interpret that information in the context of your exact situation, which leads me to:

2. You Can’t Be Objective About Your Health

Once you’ve weeded out the chaff and are dealing with a relevant set of facts, then you can work on applying those facts to your situation. But you’re going to need third-party, objective assistance. Think about it from the analogous and infinitely more obvious perspective of mental health. You can read a thick stack of self-help books, listen to all the podcasts in Tim Ferriss’ copious archives, and meditate until you’re astral projecting, but often you need a therapist to help you work through your issues. Could you stumble along on your own and get by? Maybe. Is that ideal? No. Can you administer intensive psychotherapy to yourself? No.

Following that logic, should you attempt to diagnose and treat your own thyroid problems, when it is well-recognized that the symptoms of thyroid dysfunction overlap with the symptoms of just about…everything? Do you really think you can be objective enough to pick the right lab tests and then interpret them in the context of everything else that could be contributing to the way you feel? I wouldn’t even trust myself to do this for myself, and I’m a doctor.

I remember a conversation I had during a dinner with one of my favorite surgeons. He was recounting a health scare in which he had some symptoms that convinced him he had pancreatic cancer (an often fatal malignancy). Before going to the doctor, he increased his life insurance policy dramatically, so that his family would be taken care of upon his certain demise. He then visited his primary physician with a list of tests and imaging he wanted. His doctor, recognizing that there were several diagnoses more likely than cancer, said, “Why don’t we start with a few simple blood tests and then take it from there?” Of course, there was a much more innocent explanation for this surgeon’s symptoms, and he’s still alive and kicking.

The point here is: maybe you have a medical degree, or maybe you’re just a smart cookie who is good at internet research. It doesn’t matter, because neither one of you is unbiased enough to treat yourself.

3. You Don’t Understand Two Pillars of Lab Testing

In Endocrinology vs Naturopathy – Steel Cage Death Match, I described two critical components of lab testing that alternative medicine practitioners and many laypeople clearly don’t understand: know your assay and know your pre-test probability.

Know your assay. Once a number is inked onto paper, and that number is flagged as “high” or “low,” people tend to give it a lot of weight, deserved or not. You have to know the characteristics of the instrument that performs the test (e.g. is it reliable and reproducible). You have to know what substances/supplements/medications can interfere with the assay. You have to know if what you’re testing is secreted in a pulsatile fashion or has a diurnal rhythm. You have to know if the test you’re running reflects whole body stores or just recent dietary intake. You have to know if already being on treatment changes the way in which you should perform/interpret the testing. I could go on, but I think you get the idea.

Know your pre-test probability. This often comes into play when you want me to review the 7 pages of worthless labs your naturopath ordered. There are flags on every page, so why do I often tell you “don’t worry?” Because – the vast majority of the time – I have zero clinical suspicion that you have any of the conditions for which you’ve been screened. Therefore, a mildly abnormal screening test has a near 100% probability of being a false positive.

Sadly, even when people appear to understand that knowing your assay and knowing your pre-test probability are crucial, they remain invested in performing lab work of dubious value. See if you can diagnose a lack of insight in the author of this comment on my post, Everything You Never Needed to Know About Reverse T3**:

The title of this article is horribly misleading. You should rename it. Call it something like “Why reverse t3 testing is useless.” I came to learn about reverse t3 based on the title of the article and got a thorough education about why it’s bullshit.

I took two things from this comment. One, the title of my piece was clearly perfect. Two, the commenter wants to hear only one side of the reverse T3 argument – the misguided one that promotes using it to guide the diagnosis and treatment of thyroid conditions. Despite reading my thorough debunking of rT3’s purported utility – which should save her from spinning her wheels with useless testing – she seems intent on pursuing additional “education” that will tell her what she wants to hear. To my way of thinking, this is strong evidence that people can’t be trusted to make good decisions when ordering their own lab work.

4. Ordering Unnecessary Tests Can Kill You

I realize #4 seems like a histrionic statement, but I assure you it isn’t:

A 50 year-old woman with nonspecific symptoms of fatigue and weight gain does some internet research and believes she must have hypothyroidism. She checks a “full thyroid panel” which shows a TSH in the lower half of the normal range, a normal FT4, a FT3 a hair under the lower limit of normal, a mildly elevated reverse T3, and negative TPO antibodies (spoiler alert: her thyroid function is normal based on this testing).

Using the crowd-sourced power of the internet, she becomes convinced of her hypothyroidism diagnosis and visits her doctor to obtain a prescription for pig thyroid. Her doctor attempts to explain why her lab results do not support a diagnosis of hypothyroidism. Expecting this might happen, she dismisses her doctor as under-educated and goes online to buy some pig thyroid (you can get anything on the dark web nowadays).

After a few doses of the medication, she feels amazing. Within a few weeks, however, her symptoms start returning. Not realizing that this is the stimulant effect wearing off, she increases the dose. For another few weeks, she feels amazing again, but then she regresses to her baseline state.

She continues to repeat this cycle over the course of a year. However, instead of feeling only increased energy and mental clarity every time she increases the dose, she now has the added symptoms of heart palpitations, tremors, and profuse sweating. At one year into this debacle, she has the abrupt onset of facial droop, weakness, and trouble speaking/breathing, at which time her husband rushes her to the ED, where she is diagnosed with an embolic stroke secondary to atrial fibrillation, which is secondary to self-induced thyrotoxicosis.

She gets admitted to the hospital, where she is placed on a ventilator and blood thinners. Unfortunately, her ICU stay is complicated by ventilator-associated pneumonia and a massive GI bleed. Despite reversing her anticoagulation, giving her multiple blood transfusions, and treating her with broad-spectrum antibiotics, the combination of septic shock and hypovolemic shock leads to multi-organ failure and she dies.

I know what you’re thinking: This won’t happen to me. I’m smarter than her. She must have had other problems that predisposed her to this outcome. HD exaggerates; this stuff doesn’t actually happen.

Wrong on all counts.

5. Ordering Unnecessary Tests Is A Waste Of Money

If you want to pay out-of-pocket for $1000 of unhelpful testing, then I will concede that #5 is less of an issue. However, Americans expect their medical insurance to pick up much of the tab for all blood work, so I think #5 is highly relevant.

Not only is the testing expensive, but the downstream costs can add up. The “abnormal” results will almost certainly be followed by at least one medical specialist consultation, plus followup care, plus more labs – all for something that probably shouldn’t have been investigated in the first place. Not to mention the emotional toll of thinking you have a host of medical problems, only to come to my office and learn that you’ve embarked on a fruitless wild goose chase.

Going back to the tragic story of the woman who died from complications of self-induced thyrotoxicosis, also consider the financial costs associated with ED visits and hospitalizations – the two most expensive forms of acute care in the United States. You know who winds up paying for hospitalizations that cost hundreds of thousands of dollars? You and I do, in the form of higher insurance premiums, higher deductibles, and fewer covered services.

Listen, if I decide to retile my fireplace and make a massive mess of it, who’s on the hook for having a professional come out and fix my drywall – my homeowner’s insurance? Guess again: it’s all on my tab, guys. But the woman whose pig thyroid experiment led to her demise? We all pay for that fiasco. Americans tend to be keen on the concept of individual autonomy, but given our unsustainable, escalating healthcare costs, somebody needs to step in and be the sensible parent here.


It is not lost on me that many of my readers have been struggling with symptoms that have been misdiagnosed, mistreated, or have defied diagnosis for years. In some cases, your mainstream physicians have let you down in myriad ways. Through this blog and others, you’ve learned that alternative medicine provides little more than a path to wasting your time and money. This begs the obvious question: what the heck am I supposed to do if my doctor isn’t helping me and my naturopath is selling snake oil?

If I possessed an easy answer to this question, I promise you I would have shared it years ago. It turns out that these situations are incredibly difficult and made more confusing by the fact that you do need to take matters into your own hands – to an extent. You need to check your assumptions (e.g. I’ve already tried everything) at the door and do the deep dive into your diet, exercise, sleep, relationships, stress management, and mental health. You need to abandon the (usually) irrational hope that there’s one smoking gun to explain everything and a single silver bullet that will fix it.

Will that lead you to better health? Maybe. At worst, it’s not going to hurt.

*Now that the iPhone has swipe-texting, is it as satisfying to “swipe” an angry message as to bang it out with your thumbs?

**If you are an Endocrinologist in practice or training, and you haven’t yet read Everything You Never Needed to Know About Reverse T3, you should check it out. I’ve gotten feedback from academic Endocrinologists that they love this post and make all their trainees read it.

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Image Credit: Photo by Kyle Brinker on Unsplash

20 Replies to “Top 5 Reasons Why You Shouldn’t Order Your Own Blood Tests”

  1. I am a practicing internist of about, oh, say “mid-life.” Meaning, x about 20 years…
    And the older and more experienced I get, the more afraid I am of our simple screening tests where patients DO have some average pretest probability–because I’ve seen patients die from simple colonoscopies! Your #4 is RIGHT ON.

    Every single day, we are managing benefits vs. risks. I’ve found patients have a very hard time understanding what this means. I can’t quite articulate why that is yet, or the specifics of it, but I think its related to the bias you discuss. They seem to be predisposed to see either everything as risks (“No, I don’t need any mammograms; they can cause cancer…”), or everything as benefit (“But the T3/antibiotics/prednisone/phentermine helps me…”).

    1. Candace, I know what you mean. I addressed some of what I believe is behind a lot of the misunderstanding out there in:

      Top 10 Reasons Why Smart People Are Stupid About Their Health

      Also, I think alt med fans the flames by telling your patient: “Dr. Walkley doesn’t do the kind of deep dive into your medical issues that I do.” Then alt med orders multiple pages of stuff like CMV and EBV titers, which results in a few “abnormals,” which results in the patient becoming alarmed that the great Dr. Walkley – who the patient used to trust – didn’t think to diagnose these “infections.”

      You are also right about the binary way many people look at testing/drugs/etc: “Fosamax causes your bones to be brittle and break – I would never take that.” It can be tough to educate people about the nuances of risks, benefits, and why sometimes one outweighs the other.

  2. Great article once again!
    I would like to add cardiac stress testing to the list of tests that have these same concerns. I sure wouldn’t want a stroke during an unnecessary angiogram for a stress test I never should have gotten!

    I particularly liked that you suggest we take “the deep dive into your diet, exercise, sleep, relationships, stress management, and mental health. “
    Some people have insight into where they stand on this and others don’t!
    It is hard to know where one stands on this spectrum since you don’t know how other people feel and think.

  3. The amount of crap info out there is staggering. I wasted a year of my life trying the pig thyroid to lose my sanity with anxiety and see my bone weight diminish. Then I found your blog and good advice.
    It’s amazing what balanced nutrition, exercise, sleep, prayer and social time can do for your health. Once I got those ducks in a row and I eliminated my little T3 booster dose, I lost 26 pounds, gained muscle, gained bone weight and my depression is gone!
    Thank you again for sharing your knowledge. It saved my life!

    1. I wasted years of my life on pig thyroid as well! Almost 6 years of adjusting doses, highs/lows, panic attacks, heart flutters, and then ultimately my body began rejecting the medication (headaches/dizziness/elevated blood sugar as soon as I’d take even the lowest dose) and my only option was to quit cold turkey and go on T4-only medication. And let me tell you, the “come-down” from quitting cold turkey was absolutely horrible for me, I lost months of my life. I found this blog during that dark time, found a conventional endo, got on a reasonable dose of Tirosint (no more T3!) and feel so much more balanced. I am very grateful for all of your work, HD! This blog saved my life as well!

  4. Great post HD. #4 is very scary – I wonder how many people out there are on pig thyroid / T3 who don’t need to be. The stimulant effect is never mentioned on these internet groups – “you feel great” = “you found the magic fix, but you just need the exaaaaact right dose, to be changed every three weeks with repeated blood tests”.

    One funny thing about the internet quackery is that they all say “oh you can’t trust blood tests and the “normal” ranges, you have to base it on your symptoms” but then turn around and decide because the T3 is under some specific high number by 0.1 that it warrants treatment….. If I was typing on my phone I would add the emoji for ‘I don’t get it’.

    1. One funny thing about the internet quackery is that they all say “oh you can’t trust blood tests and the “normal” ranges, you have to base it on your symptoms” but then turn around and decide because the T3 is under some specific high number by 0.1 that it warrants treatment…

      Preach, Emily, preach!

      1. I honestly don’t know why I stay in the thyroid facebook group I’m in – it’s almost a guilty pleasure reading all the BS (and occasionally trying to direct people here) – but often I just get frustrated

  5. Some good points here. I think if someone is having bad luck with a doctor, it’s time to find another doctor. I’m on my 5th endocrinologist and so far I’m very happy. I wouldn’t say all of the other ones were bad, and I actually learned something from each of them (not all where local, so that’s part of why I have been through many). Why I left my previous doctor is my TSH was high (5) and she wouldn’t up my medicine. Doing much better now on a slightly higher dose and TSH 2.5. Since I’m feeling better we (current doctor) decided to stick with this current dose even though I wanted to be between 1 and 2.

    I think even if you decide to do some alternative concepts like a special diet, supplementation, etc…you should have an endocrinologist or PCP helping. Just find one that lines up with your goals. And realize they are not likely to be alternative.

  6. I always forget that anyone can get labs and medications on the friendly internet. Lots of options show up if you google it and I will not link them because I really do not want to promote it. I am surprised how much it costs. I guess that is why I do not see too many people bringing in their own labs.

    Develop a good relationship with your PCP. If you are a normal person and follow recommendations for years then come in with an odd complaint I can tell you that it will get more attention then the noncomplient person who has a handful of symptoms at each visit.
    If your PCP suggests ordering fancy thyroid testing or hormone or vitamin levels I suggest you find a new PCP. They are either incompetent or looking to make money. If you ask them too and they do so willingly without trying to suggest the healthy lifestyle advice in the post then they are too much a people pleaser to be an objective clinician.

    Great post and great information. Thank you for bringing some sanity to the internet.

    1. Great point about people-pleaser docs. With the advent of patient-satisfaction scores playing a more prominent role in physician compensation, I expect that more doctors may be tempted to treat patients as consumers – which they are not. Not to mention that it can be exhausting to fight these battles with patients when careful explanations do not dissuade them from what they think they need.

  7. I have a question I hope you won’t mind answering. After a doctor diagnoses hypo, is it important to find out if it is hashimotos or not? I really would like to know but is it important? I was first diagnosed with alopecia areata after my hair fell out of the side of my head and then after testing TSH, aslo hypothyroid. I now have good days where I feel like the old me before my daughter was born 8 years ago but I am also having down days where my symptoms come back but not as severe as they were. Is that something to talk to my doctor about or something to brush off since many days I feel normal again. I don’t want to seem crazy to my doc so I haven’t really asked for anything and have just followed her lead.

    1. Erin, as a fellow patient I think it’s important to know. Most likely it is Hashimotos if you live in the U.S or other developed nations. But 10 percent of the time it isn’t. So why not know what you are dealing with? While most doctors (including the blog writer) don’t think you can address the autoimmune issue, I think it can be addressed. So if you have high antibody counts, it’s worth considering trying to get those down. And most of the items the blog writer suggests are items that can bring them down (exercise, diet (avoiding processed foods), Nutrition, stress reduction, filtering water, better skin products, etc. Selenium can bring them down a bit, but don’t over do that one. A brazil nut a day or 100 a day of a supplement. This is a path I rather take then having more damage done and having to increase meds over time. All that being said, getting your thyroid levels correct is very important. TSH levels between 1-2.5 would be best if on T4 medication. Nutrient deficiencies can cause issues and can be common. Vitamin D especially, Iron, B12, etc.

    2. As a general rule, the treatment for primary hypothyroidism isn’t going to be significantly different if we determine that the cause is Hashimoto’s vs not. I’ve written plenty (see the Thyroid tab of this website) about the things people have tried to stop the autoimmune attack; while much of what people try isn’t harmful (better diet, exercise, etc), it mostly doesn’t affect the natural course of the antibody attack.

      1. Unless it’s something like iodine deficiency or medications causing it…not common I suppose but possible. Always be very careful with Iodine though. It’s something where too much or too little is not good. I’d imagine more studies are needed to be sure those efforts don’t affect the course of the attack. It would seem logical that lowering antibodies from 2000 to say 100 would be beneficial. However, I understand sometimes how aggressive the attack is is not related to the amount of antibodies. Which is in itself an interesting subject. I’d be interested in an endocrinologist’s take on antibodies and their relation to the well being of a patient. Other than if they are high they are high. Antibody levels have shown up in many studies and I’m sure they had a reason to do those studies.

        1. This study seems to point to what you are saying on antibodies. Any thoughts on this discussion? Sounds like they can cause damage, but not as much as the other stuff they discussed:

          Antibodies against TPO (TPOAbs) and Tg (TgAbs) are of immunoglobulin G class, both showing high affinity for their respective antigens. Unlike TgAbs, TPOAbs can activate complement and are able to cause damage to thyroid cells due to antibody dependent cell cytotoxicity [3]. Nevertheless, there is little evidence that both antibodies have a prime role in the pathogenesis of HT and it is far more likely that both T-cell mediated cytotoxicity and activation of apoptotic pathways influence the disease outcome. However, TAbs serve as a useful marker for the diagnosis of thyroid autoimmunity. In HT, TPOAbs are present in nearly all (>90 %) patients, while TgAbs can be detected in approximately 80%

      2. Okay, thank you. for your response. I try to be healthy in general and recently even more so. My weight is normally 130 lbs but shot up to 149. I am now down to 143 but keep bouncing between 139 and 144. So I have been working out and eating healthy. Just trying to be healthy. I’ll wait and see if I get more stable and maybe ask my Doc about it next time to have to get tested and adjusted. 2.3 is where we are keeping my TSH I suppose. I am learning a lot from this website, thank you.

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