The main function of the thyroid hormone is to regulate metabolism, which is the process through which your body transforms the foods you eat into energy. Though referred to as a single hormone, the thyroid “hormone” actually consists of two hormones — triiodothyronine (T3) and thyroxine (T4). Together, these two help regulate several key bodily functions.
As its name implies, the thyroid hormone is a hormone produced by the thyroid — a small, butterfly-shaped gland that sits at the front of your neck. The thyroid is just one component of the endocrine system. In infants, the thyroid is crucial for brain development. However, as children grow, it becomes less responsible for brain development and almost solely responsible for metabolism. More specifically, it controls the speed at which your body processes food into energy. Faster working thyroids mean a faster metabolism. Conversely, thyroids that function at a slower pace mean a slower metabolism.
As all hormones do, the thyroid hormone coordinates one to a handful of specific functions in the body. It does this by using the blood stream to carry messages to the muscles, organs and other tissues throughout the body. These messages tell the body what to do and when to do it.
The thyroid hormone plays the hugely important role of regulating metabolism, which is the process of transforming food into energy. Every aspect of the body relies on energy to function optimally.
The thyroid hormone is actually comprised of two distinct hormones: Triiodothyronine (T3) and thyroxine (T4). The thyroid produces both T3 and T4. It is standard practice for them to be referred to as a single hormone because T4 is largely inactive, meaning it has no impact on cells. T3, on the other hand, is active. Once the thyroid releases both hormones, T3 particles locate their T4 counterparts and transform them into more active T3s through a process called “de-iodination.” De-iodination is necessary because most cells lack receptors that can accept T4, therefore rendering them useless to most cells throughout the body.
Though the thyroid produces mainly T3 and T4, it also releases a hormone called calcitonin. Calcitonin’s job is to regulate calcium levels in the blood by decreasing it. Though technically a thyroid hormone, it is not considered “the” thyroid hormone, as its job has nothing to do with the metabolism.
Many organs, tissues, glands and bodily systems have the capacity to convert T4 hormones into the more active T3s. The components that can do this majorly benefit from the thyroid hormone. Some components that benefit from T4 and T3 are as follows:
Even though a few bodily systems cannot convert T4 to T3, every aspect of the body benefits from the thyroid hormone. A few key functions that occur because of T4 and T3 are as follows:
These are just a few key roles the thyroid hormone plays throughout the body.
The thyroid is a small, seemingly insignificant gland located in the neck. Though underrated, it is responsible for producing the thyroid hormone, which is almost solely accountable for regulating metabolism. The metabolism is a crucial bodily function that regulates how the body uses energy and at what rate. Too quick of a metabolism can cause a person to become underweight, while too slow of a metabolism can lead to obesity. Neither outcome is good. Having a properly-functioning thyroid is critical to maintaining a healthy weight and, ultimately, optimal overall health.