Causes of Thyroid Dysfunction

Dr. Ruscio provides a simple overview of the causes of thyroid dysfunction. He then covers 2 example cases of what this looks like in real life. This should help you easily understand the common causes of thyroid dysfunction and what practical diagnosis and treatment of these cause should look like.

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Causes of Thyroid Dysfunction

Dr. Michael Ruscio: Hi. This is Dr. Ruscio, and welcome to the next video in our hypothyroid series on what causes hypothyroidism.

And, this is a really important thing to ask because, until we know what is causing the hypothyroidism, all we are really doing is treating symptoms.

So, coming back to our model that we went over in one of our last videos on general thyroid physiology. Remember we have the pituitary in the brain secretes a hormone called TSH that tells the thyroid to make a hormone called T4, that then must be converted into T3 or activated. And that’s what you are seeing in this (slide) here. Now, I’ve broken down the multiple factors that can cause thyroid dysfunction per area in the body that can cause thyroid dysfunction. So, of course, anything that interfers with pituitrary function, or the release of the hormone called TSH from the pituitary that travels down to the thyroid is one are that is implicated in causing hypothyroidism.

So, here we see three things: inflammation, toxicity, and stress hormones. You see asterisks next to inflammation and stress hormone because those tend to be the two most prevalent and impactful factors for patients. The most so, and why there are two asterisks next to inflammation is inflammation because that seems to be an issue that affecting many, many patients – when we look at their blood work, we see high inflammation to a greater or lesser extent in the majority of patients that we examine.

Toxicity – although mercury toxicity and other toxins have received a lot of attention, I guess you would say, in the recent pop culture and in health care and medicine, they don’t tend to be a primary issue with most patients. Once we clean up their diet, and once we get their body working a little bit more effectively, most toxicities tend to take care of themselves. Probably the most well-know is mercury, which, again, as someone who use to to test for mercury in almost all patients, and did a lot of work to detoxify it, have not found it to be the most important factor on the table. Certainly for some patients it can be, but I would not say it’s one of the most important.

However, stress hormones tend to be very important. High levels of stress hormones will suppress TSH secretion, and actually, low levels of of stress hormones – as we’ll talk about in a moment – will interfere with the conversion of T4 into T3.

Now, moving down our list here, we see things interfere with low thyroid function directly. Now, the most important here, and as we’ve discussed the most common cause of hypothyroidism, is autoimmunity, or what’s known as Hashimoto’s. Since this is such important topic, I am going to dedicate a whole video to Hashimoto’s and autoimmunity in and of itself. So, we are going to skip over that one right now, but it’s very important, and we will certainly come back to that one.

Now, nutrient deficiencies are also something that can cause low thyroid function, so a problem in the thyroid gland itself. Deficiencies in the amino acid tyrosine, iodine deficiencies – although iodine deficiencies are not very common in any industrialized country, especially not in the United States – selenium deficiencies, and the third item here is low progesterone. A way you can conceptualize this is: The reason why women, when using fertility charts, will see their body temperature increase in the second half of their cycle is  because after a woman ovulates, here progesterone levels go higher and progesterone has a vacillatory impact on thyroid hormone.

So, we know that a deficiency in progesterone can interrupt the ability of the thyroid gland to make thyroid hormone. So, female hormones can definitely be important.

Moving further down the list, low thyroid activation – we see a few things listed here: Liver toxicity, because remember from our chart over here that 60 percent of thyroid hormone is activated, or turned from T4 to T3 in the liver. Also remember that 20 percent of thyroid hormone is activated or converted in the intestines. So, that’s why digestive problems are so important. You see the two asterisks next to digestive problems because they tend to be very, very important. Almost every patient has a greater or lesser extent of a digestive problem that is very helpful to that patient once we resolve that.

Really, digestion and inflammation go hand-in-hand because, arguably, the primary source of inflammation in the body will be the digestive tract. So, if someone has a digestive issue, that in and of itself is a problem, but that issue will also cause inflammation. And then inflammation will be a problem further still. So, digestion and inflammation are two very important factors.

And then we also see again stress hormones. And here, if the stress hormones – which actually is more common than one might think – you have decreased conversion of the T4 hormone into T3.

Finally here we see high estrogen or low testosterone. High estrogen will actually block the ability of thyroid hormone to work, as will low levels of testosterone. So, the female hormone connection we can see here (is) between high estrogen and low progesterone, which is a fairly common pattern. When a woman goes into a chronic stress response, the typical skewing of the hormones will be a lowering of progesterone and an increase in estrogen just do to the stress hormone’s impact on the female hormones.

So, this is our list. These are the things that we investigate in the clinic. When a person comes in complaining of hypothyroidism, we look through all of these factors. We find a number of these for each patients. When we treat these, this is when we really see lasting improvement in the symptoms.

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So, to go over two quick examples of how we apply this, Sarah and April both present to the clinic hypothyroid. Now, when preforming the history, Sarah said she started having thyroid problems after her second pregnancy. When we do a laboratory investigation on Sarah, we see elevated DPO antibodies, which is how you diagnois Hashimoto’s. So, this would classify here as postpartum or post-pregnancy autoimmune hypothyroid. And pregnancy is one of the factors known to provocate autoimmunity, as we will talk about more in our video on autoimmunity.

So, the treatment for (Sarah) looks like balancing of the immune system to stop the autoimmune attack or the autoimmune damage to the thyroid. This consists of dietary changes, antioxidant therapy, and vitamin therapy.

This is a different treatment program than we see for April, who also presented with hyperthyroid, but mentioned her digestion isn’t as good as it use to be – she has gas, bloating, and stomach burning on occasion. And this all started about five years ago. When we go through laboratory and diagnostics for her, we see an H. pylori infection – which is a bacteria that lives in the stomach or intestines, and high-reverse T3, which we spoke about earlier. This would classify here as infection-induced high inflammation resulting in decreased thyroid hormone activation or decreased conversion of T4 into T3.

So for her, the treatment will be different than it was for Sarah. We’ll want to remove the gut infection and repair the gut. This will consist of antimicrobial herbs, vitamin therapy, and the correct regimen of probiotics.

So, as you can see here, two patients come in with the same complaint. Yet, when we take the time to investigate, we have completely different causes, and, therefore, completely different treatments.

So, hopefully some of what we’ve covered resonates with you, and you’re starting to see that, if you have the complaint of hypothyroidism, we really want to investigate and determine what it is that is causing that complaint. Once we know what causes it, we can treat that cause. And when we treat that cause, we can have a very high level of improvement.

So, this is Dr. Ruscio, and I hope you find this helpful. Thanks.


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