I’ve written about thyroid nodules in the past, as many people with thyroid and autoimmune thyroid conditions have nodules. I’ve also written about insulin resistance, as this is also commonly seen in people with thyroid imbalances. This is especially true for those people with hypothyroidism and Hashimoto’s thyroiditis, although it can also affect those with hyperthyroidism and Graves’ disease. But there is also evidence that insulin resistance can be a factor in the development of thyroid nodules, which of course will be the focus of this blog post.
I’m frequently asked how to shrink thyroid nodules by patients and non patients. The truth is that there is no specific natural treatment approach for all thyroid nodules. The obvious goal should be to find and address the cause of the thyroid nodules, which isn’t always easy to do.
Other Causes of Thyroid Nodule Formation
Although the focus of this blog post will be to discuss the relationship between insulin resistance and thyroid nodules, there can be other causes. Two of the more common ones are an iodine deficiency and problems with estrogen metabolism. As a result, it makes sense to determine if someone has these imbalances.
There is no perfect method of determining whether someone has an iodine deficiency, although urinary testing is preferred by many healthcare practitioners, including myself. For example, when I was diagnosed with Graves’ disease I ordered an iodine loading test. The downside of this test is that it requires ingesting a 50mg tablet of potassium iodide, and not everyone does well when taking this. Another option that doesn’t involve consuming iodine is an iodine spot test, which is a one-sample urinary iodine test. Although some people test for iodine in the blood, normal serum iodine levels doesn’t rule out an iodine deficiency.
As for determining whether or not you have problems with estrogen metabolism, blood testing of course is one method that can be used to measure the estradiol levels. Saliva and urine testing is also an option, and without question are superior options for cycling women. The reason for this is because a cycling hormone panel allows cycling women to collect multiple saliva or urine samples throughout their cycle. This is more accurate than collecting a single sample in the second half of the cycle, although it also is more expensive.
However, measuring the estradiol levels won’t always indicate whether someone has estrogen metabolism issues. For example, the enzyme catechol-o-methyltransferase (COMT) is involved in estrogen metabolism. As a result, if someone has a genetic polymorphism of the COMT gene then this can affect estrogen metabolism. Having elevated levels of an enzyme called beta-glucuronidase can also prevent the excretion of estrogen.
What Is Insulin Resistance?
Although I would recommend to read other articles I’ve written on insulin resistance [1] for more detailed information, I’ll briefly explain what this is here. Insulin is a hormone that is produced by the beta cells of the pancreas. As the name implies, insulin resistance is when the cells are no longer sensitive to insulin. So this is actually a high insulin state, which is why this is associated with pre-diabetes and type 2 diabetes. Although some doctors rely on a fasting glucose test to determine if someone has insulin resistance, other testing is recommended to make a diagnosis, including a fasting insulin and a hemoglobin A1C. Sometimes a glucose tolerance test will also be used. Elevated triglycerides on a lipid panel are frequently a sign of insulin resistance.
As for how insulin resistance develops, there is no question that eating a diet consisting of high amounts of refined carbohydrates and sugars is a factor. A high intake of fructose can especially be problematic, as this can lead to an increase in fat deposition in the liver and skeletal muscle, thus increasing the risk of insulin resistance and type 2 diabetes (1) [2]. And when I say that high amounts of fructose can be a factor in the development of insulin resistance, this is especially true when fructose is used as a sweetener in processed foods and beverages. This doesn’t mean that you can’t overdo it with fruit, but eating a few servings of fruit per day isn’t going to cause insulin resistance in most people.
While one’s diet can play a big role in the development of insulin resistance, there can be other factors. Inflammation is a big factor, and there are many different causes of inflammation. Since the mitochondria play a role in glucose homeostasis, mitochondrial dysfunction can also be a factor. There is even evidence that intestinal dysbiosis can cause insulin resistance (2) [3], which is yet another reason to do everything you can to improve the health of your gut.
What Does The Research Show?
One study examined the prevalence of insulin resistance in a case-control study of patients with benign thyroid nodules (3) [4]. These patients lived in an iodine-sufficient area, and as a result, an iodine deficiency was unlikely to be the culprit, although in my opinion it still would have been worth testing to determine if they had an iodine deficiency. In any case, the study showed that there is an association between insulin resistance and benign thyroid nodules. Another study looked at the association between insulin resistance and the vascularization of thyroid nodules (4) [5]. The authors of the study concluded that there is a vital role of insulin resistance in the distribution, construction, and density of thyroid nodular vascularization, and that this in turn might contribute to the growth and the progression of thyroid nodules.
Yet another study looked at the relationship between insulin resistance in those with euthyroid nodular goiter (5) [6]. For those who are unfamiliar with the term “euthyroid”, this refers to someone who has normal thyroid hormone levels. In any case, the results showed that insulin resistance may cause an increase in thyroid cell proliferation and nodule volume, as well as nodule formation. I’ll mention one more study that looked to see if there was a correlation between insulin resistance and thyroid nodules in those with type 2 diabetes (6) [7]. The results of the study demonstrated that insulin resistance was a risk factor for thyroid nodule formation in patients with type 2 diabetes.
3 Steps You Should Take If You Have Thyroid Nodules
Based on the information presented in this article, if a thyroid ultrasound reveals that you have one or more thyroid nodules then you should take the following steps:
Step #1: Modify diet and lifestyle factors. Regardless of what imbalances you have, it will benefit your overall health if you eat a healthy diet. This is especially true if you have insulin resistance, although it can help with other health issues as well. And of course it won’t hurt to address other lifestyle factors, which includes improving your stress handling skills and getting sufficient sleep.
Step #2: Do the appropriate testing. In this blog post I discussed three factors that can lead to the formation of thyroid nodules, including an iodine deficiency, problems with estrogen metabolism, and insulin resistance. I also discussed how to test for these imbalances.
Step #3: Correct any imbalances found through the testing. You of course would want to correct any imbalances that show up on the testing. Sometimes this is easier said than done. For example, if you have an iodine deficiency, then you might need to improve other aspects of your heath before correcting this deficiency. I’ve spoken about this in an article I wrote entitled “An Update on Iodine and Thyroid Health [8]”. As for how to correct a problem with estrogen metabolism, I would recommend reading an article I wrote entitled “7 Ways To Positively Influence Estrogen Metabolism [9]”.
But of course the focus of this blog post is on insulin resistance as being a factor in the development of thyroid nodules. And while many times following the first step will help with this, other times this won’t be sufficient. Earlier I mentioned some of the other factors that can play a role in the development and perpetuation of insulin resistance, including inflammation, mitochondrial dysfunction, and intestinal dysbiosis. I’ve discussed all of these factors in different articles and blog posts.
Will following these three steps result in the shrinking of your thyroid nodules? Perhaps, although you need to keep a few things in mind. First of all, it’s not always easy to find and correct these imbalances. You need to find the imbalances that are responsible for the formation of thyroid nodules, which can be challenging at times. And then even if you find the imbalances, correcting them can also be a challenge. For example, I briefly mentioned the challenges of correcting an iodine deficiency earlier.
I also mentioned that there can be numerous causes of insulin resistance. So even if you have confirmed that you have insulin resistance through testing, it isn’t always easy to find what specifically is causing the insulin resistance. This doesn’t mean that you shouldn’t attempt to find out the cause, but just remember that doing so can be challenging at times.
So hopefully you have a better understanding of the relationship between insulin resistance and thyroid nodules. Some of the common causes and contributing factors of insulin resistance include poor diet, inflammation, mitochondrial dysfunction, and intestinal dysbiosis. Two other common causes of thyroid nodules include an iodine deficiency and problems with estrogen metabolism. As a result, it makes sense to do the appropriate testing to find out what imbalances might be causing or contributing to your thyroid nodules, and then correct any imbalances that are found.