When you hear the word thyroid, chances are you immediately think weight gain. Maybe you remember a few years ago when Oprah revealed that she had an underactive thyroid, which was likely the cause of her gaining her weight back.
Yet what I tell my patients and what I want you to know is that the thyroid is so much more than metabolism. Sure, it’s small. But it’s a super-gland that is quite complex.
It affects so many different processes in your body, and whether it works at an optimal level or not depends on several factors.
What does the thyroid do?
I like to think of the thyroid as your body’s car because it decides how fast or slow your body should run. The thyroid is a small butterfly-shaped gland located in the center of the lower part of your throat. It’s made up of right and left lobes on either side and the isthmus in the center.
The thyroid produces two major hormones: T3 and T4. They’re like partners in crime for your thyroid. They travel throughout the blood, come in contact with all of the cells in your body and their thyroid receptors, where they stimulate your metabolism. Every cell has these receptors because they make energy or fuel for your body to run well.
So this is how the process works.
Your cells burn fuel in the form of glucose (a type of sugar) and fat. Glucose and fat are your body’s primary sources of energy, but they can’t burn that energy when there isn’t the right amount of T3 and T4.
And what may surprise you is that your brain actually dictates everything your thyroid does.
Your brain secrets the thyroid-stimulating hormone (TSH), which then goes directly to the thyroid. The thyroid then pushes out the hormone T4 that moves to the liver and is converted there to T3 – in a ratio of 4:1.
This happens because T4 is on actually reserve, waiting to be told by your body to go into full effect as T3. This is important because if your body was constantly in T3 mode, you would be in overdrive. So having both hormones allows the body to modulate itself depending on when you need more of one or the other.
So let’s look at what happens at the cellular level.
The thyroid receptors on the cells act like antennas — constantly sensing if T3 is too high, too low, or just right. The receptor then brings that information back to the brain and the cycle starts again.
As you see, your brain, thyroid, and cells are like your body’s own little command station, ensuring your body runs at maximum capacity.
Sometimes, however, one subtle change can cause your thyroid to dysfunction and wreak havoc on your body (more on that later).