In medicine, hypothyroidism and anxiety aren’t typically associated. It is usually depression associated with a low thyroid function and anxiety with high. But many of my patients found their anxiety disappear with proper thyroid function. Why is this? Could low thyroid be the answer to treatment-resistant anxiety? Many patients come to me taking thyroid but are not feeling better. Others presented with subclinical hypothyroid. Why is this? Let’s explore more about these issues. I should note that hormone interactions in the body are very complex. This article does not serve as a full primer but a short introduction.
Before jumping into the complexity of hormones, I want to review the scope of the problem. Anxiety occurs in 30-40% of patients with hypothyroid. They can also have irritability, depression, learning issues, and poor concentration.
The Causes of Hypothyroidism (and Anxiety)
Most research suggests that doctors should not give medications for depression and anxiety until they check thyroid levels. While I agree with the approach in theory, it’s not as simple as testing thyroid.
To understand the paradox of this problem, I want to explain a bit about the hypothalamic-pituitary axis (HPT). This may be technical but bear with me. The hypothalamus and pituitary are in the brain, controlling hormonal function in the body through different hormones. The hypothalamus produces Thyrotropin-releasing hormone (TRH) to signal the pituitary to make thyroid-stimulating hormone (TSH). TSH signals to the thyroid to produce T4 (Thyroxine) which is stored in the thyroid gland until the body needs to use it. When the body needs energy, T4 converts to T3 (Triiodothyronine).
Because T3 is so potent, the body only converts what it needs when it needs it and mostly inside the cell. T3 then crosses into the nucleus and started turning genes on. If you have listened to my podcast about methylation and epigenetics, there may be a connection here. Remember that everything you eat, drink, breathe, and experience can change your genetic expression. Specifically, high or low methyl may affect T3 binding at specific sites, thereby producing different results. The following are required for the thyroid to work:
- Hypothalamic/pituitary function
- Secretion of TSH
- Thyroid function (secretion of T4)
- Thyroid hormone transport into the cell
- Conversion of T4 to T3
- Receptor binding
- Downstream activation
There are a lot of steps. I want you to remember this list because it will be important in a moment.
But the doctor said my thyroid levels were normal!
Both the tests for thyroid and their interpretation are problematic. Typically, most doctors only run a TSH to see if thyroid is functioning well. But many recent research studies suggest that TSH is a poor measure of thyroid function. Several studies concluded that looking at just TSH does not show how cells are utilizing thyroid.
Some doctors know this and also measure T4 to determine thyroid function. There are problems with this approach. First, both TSH and T4 measure supply of thyroid hormone. A normal TSH means that the pituitary receives the message from the hypothalamus to tell the thyroid to produce thyroid. When these numbers are normal, most likely, your thyroid is working. But often in hypothyroidism, the problem stems from somewhere further downstream from the gland. Look at the list above. There are four more steps below the level of the thyroid that can lead to hypothyroidism.
More Problems with Thyroid Tests
If TSH or T4 is off, most clinicians give T4! That helps nothing further downstream, and it could make things worse for many people too. Why? Because the body may convert too much T4 to reverse T3. This blocks the receptor sites for good T3 but no cell activity changes. Reverse T3 also stops conversion of T4 to T3. When this occurs, treatment to reduce reverse T3 must be given before thyroid function can return to normal.
The other big problem with this testing is that it presupposes that if there’s T4 that the T4 is getting into the cell and the body is converting it all to T3. But that is not always the case.
But my doctor tested the T3 and it was normal!
I’ve done that too but what we are finding that measuring T3 and T4 are not always good indicators of thyroid function either. One problem is that T3 is an intracellular component meaning that we don’t see a lot in the blood. Therefore, doing a blood test tells us nothing about how the cell is utilizing T3.
But the biggest problem with these tests is that many common conditions skew the results. For example, patients with fibromyalgia have low normal TSH normal T4 but low T3. Doctors typically treat these patients as though their thyroid is either normal or on the high end. Patients who are obese typically have thyroid results that do not correlate with their symptoms. The same is true of patients with high levels of inflammation and diabetes.
Many conditions may be issues of conversion of T4 to T3. Why is this happening? Much of the research suggests that chemicals such as flame retardants, bisphenol A, plastics, heavy metals and such. These compounds may disrupt the energy production mechanisms in cells called mitochondria.
Why am I Anxious if I’m Hypothyroid?
You may wonder how this related to anxiety. The short answer is we don’t know. My best guess is that the sympathetic nervous system kicks in to speed up processes in the body. Adrenaline rushes over long periods leads to anxiety.
If you suffer from anxiety, depression, learning issues, or brain fog, it’s time to get your thyroid checked. There are better ways to test thyroid than just doing a TSH including taking your temperature or measuring other hormone in the body such as sex hormone binding globulin. This is what I do in my practice now instead of measuring just the thyroid levels. I am certified in Wilson’s Temperature Syndrome therapy, a novel approach to correct issues with thyroid conversion. In fact many people who were previously diagnosed with Hashimoto’s or other thyroid issues, regained healthy thyroid function after this treatment approach. Schedule with me if you want to learn more. Your path to feeling better is just around the corner.