Thyroid Hormones Explained

The thyroid is often discussed as an integral part of the metabolic and endocrine systems of the body, but many of us don’t understand how it works or what it really even does. Well, every single cell in your body depends on the thyroid to regulate its metabolic functions, which in turn regulates the functions of your organs, controlling things like heart rate, breathing, digestion, and the nervous system, among others. The thyroid does this through a combination of hormones that signal the body when to use energy and how to do it. If your thyroid hormone levels are higher or lower than normal, you can experience a variety of symptoms, including depression or anxiety, weight loss or gain, infertility, or irregular menstrual cycles.

Let’s take a look at how the thyroid does its job in our bodies. First of all, you need two other organs to help secrete hormones to tell the thyroid what to do. First, the hypothalamus produces Thyroid Releasing Hormone (TRH) which tells the pituitary gland it needs to produce Thyroid Stimulating Hormone (TSH). The production of more or less TSH by the pituitary communicates to the thyroid whether it should produce more or less of the thyroid hormones, T1 through T4. This can make the understanding of thyroid test results a little confusing. Tests that measure TSH will show high levels of TSH if your thyroid is underperforming and low levels if it is over-performing. Additionally, there is a difference between the designation of “normal” thyroid levels and “optimal” thyroid levels so even normal producers can be experiencing thyroid dysfunction if they are not at an optimal level.

T4 or Thyroxine is the most abundantly produced hormone by the thyroid. T4 is sent all over the body to be stored by cells so that they can convert it when needed into T3, also called Triiodothyronine. There are two types of T3 that perform very differently in the body so it’s important to differentiate between them. Free T3 (FT3) is the hormone that attaches to cell receptors to power the metabolic functions, the “accelerator”. Reverse T3 (RT3) does the exact opposite, slowing down the metabolic processes, the “brake”. If your levels of FT3 are too high, then you might be experiencing hyperthyroidism or an overactive thyroid. If FT3 is low or RT3 is high, you are likely affected by hypothyroidism.

It’s very important that hormone levels be closely examined as they can wreak havoc on your body if they aren’t regulating your body efficiently. An overactive thyroid (hyperthyroidism) can cause anxiety, weight loss, diarrhea, irritability, sweating, nervousness, hair loss, and missed menstruation. Conversely, an underactive thyroid (hypothyroidism) can cause depression, weight gain, slow heart rate, tiredness and fatigue, dry skin, frequent and heavy menstruation, and joint and muscle pain.

There are a lot of reasons that your thyroid might not be producing hormones correctly, but an important one to test for is autoimmune thyroid diseases like Hashimoto’s or Graves’ Disease. Both occur when the immune system is attacking the thyroid and can be discovered by testing for Thyroid Peroxidase antibodies and Thyroglobulin antibodies in the blood.

If you believe that you are having an issue with your thyroid, ask your doctor (or contact Denver Holistic Medicine) to perform a complete thyroid panel, testing for TSH, T4, RT3, FT3, and all thyroid antibodies. Denver Holistic Medicine has holistic treatment options for hyper and hypothyroidism and would be happy to help you get to the root of your symptoms. Contact us today to start your holistic healing.