TSH Levels – What Your TSH Levels Mean in a Nutshell


Some people may have heard about Thyroid Stimulating Hormone (TSH) levels , and how they work in your body.

But there is a lot of mistaken information about TSH levels, thyroid problems, and how important TSH levels and your thyroid actually are to your overall health and bodily functions.

And if you’ve ever done any research on the thyroid, you’ve probably encountered the indecipherable “medical speak” that you find on various sites that leave you even more confused than before when searching for information on thyroid stimulating hormones.

So we wanted to give you a “layman’s” view on TSH levels, and how your thyroid actually works in your body.

THS Levels & How Your Body Works

First off, you need to understand what your TSH levels and your thyroid actually do; and why thyroid stimulating hormones can affect your overall health.

The thyroid is a butterfly-shaped gland that sits low on the front of the neck. Your thyroid sits just below your Adam’s apple, along the front of the windpipe.

The thyroid has two side lobes, connected by a bridge in the middle. When the thyroid is its normal size, you will not even be able to feel it.

Why is your thyroid health so critically important?

Because your TSH levels are a general gauge of your thyroid activity; and your thyroid regulates nearly every cell in your body, as well as various organs and tissues.

Additionally, the thyroid is responsible for controlling energy consumption, body temperature, weight, and heart rate; as well as your overall body metabolism.

Here’s a perfect example of what your thyroid does; it works very similar to the thermostat in your house.

If the thyroid is too active and produces too much of the T4 and T3 hormones (which control your body’s metabolism), it’s like having a thermostat that’s set too high… So the house gets overheated.

If it’s not active enough, it’s set too low and the house is too cold. And if it’s making just the right amount of T4 and T3 hormones, then it keeps the temperature just right.

How Thyroid Stimulating Hormone Regulates Your Thyroid

A lot of people make the mistake thinking that your thyroid functions all by itself.

Actually, this is inaccurate. Your thyroid is dependent on your pituitary gland; another part of your endocrine system that is located at the back of the brain.

Your pituitary gland produces the actual thyroid stimulating hormone and regulates your TSH level; and it is the TSH levels produced by the pituitary gland that tells the thyroid to go to work.

Thyroid stimulating hormones are what regulate the thyroid’s production of the T3 and T4 hormones; and these T3 and T4 hormone are what control your body’s metabolism.

Here’s something that a lot of people do not consider when looking at thyroid problems.

They immediately assume the thyroid is not functioning correctly; when in actuality, they may have an issue with the pituitary gland.

You could have a perfectly functioning thyroid; but if your pituitary gland is not sending over the correct TSH levels to your thyroid telling it to go to work… Then it doesn’t.

If that is the case, you have a lack of T4 & T3 hormones being produced in your body; a condition known as “hypothyroidism”.

And the reverse is true as well.

If your pituitary gland is constantly bombarding your thyroid with high TSH levels, it kicks the thyroid into overdrive, and your thyroid starts producing too much T3 & T4 hormones.

This is what causes the condition known as “hyperthyroidism”.

Problems Associated With Incorrect Thyroid Levels

An improperly functioning thyroid and imbalanced TSH levels can affect your body in several different ways.

Consider the thermostat example once again; where “hypothyroidism” is too cold, and “hyperthyroidism” is too hot

Hypothyroidism- The “Too Cold” Example

If your thyroid is not producing enough of the T3 & T4 hormones for your body, you will develop hypothyroidism (an under-active thyroid).

You may feel sluggish, listless, and you will not have much energy.

Your hair may become brittle, your skin may become dry and pale, weight loss will become impossible to achieve, and you will constantly feel cold in a room where others are perfectly comfortable.

Kids with hypothyroidism may not grow as quickly, and may not experience the onset of puberty until treated.

In men, there is the risk of high cholesterol and infertility. In women, there is a chance of birth defects and miscarriage during pregnancy.

Hyperthyroidism – The “Too Hot” Example

If your thyroid is producing too much of the T3 & T4 hormones, you will develop hyperthyroidism (an overactive thyroid); and you are going to see the opposite effects.

You will be feeling too hot in a room that other people consider to be comfortable.

You will also get fatigued very easily, you will have difficulties concentrating, you will rarely gain any weight, you will feel constantly nervous and restless, and you may possibly develop goiters on the thyroid.

Diagnosis of Thyroid Levels

If you are experiencing thyroid stimulating hormone irregularities, your doctor will order a test to determine not only the amount of TSH in your body, but also to measure the T3 & T4 hormone levels as well.

The thyroid levels test is the best method for evaluating thyroid functions or symptoms of hyperthyroidism or hypothyroidism.

The thyroid test is used to…

  • Diagnose a thyroid disorder (either too much or too little hormonal production) in a person with symptoms
  • Screen children for an under-active or overactive thyroid
  • Monitor thyroid replacement therapy in people with hypothyroidism
  • Determine the functionality of the pituitary gland

A complete TSH levels test will include a physical examination to discover thyroid enlargement, any tremors, hyperactive reflexes, or an increased heart rate revealed by a high systolic blood pressure (the first number in a blood pressure reading).

Most often, the TSH levels test can be performed at your doctor’s office as an outpatient service; there is no need to go to a hospital or special lab to get your blood drawn for a standard TSH levels test.

Test Results of Thyroid Stimulating Hormone Levels

If you have a thyroid stimulating hormone imbalance in your body, luckily it is not life threatening. But it does cause you discomfort as your entire endocrine system is not operating at peak efficiency.

And your TSH levels test results will determine what type of treatment you need to get.

But here is where it gets confusing to most people. The test results for THS levels are actually the opposite of what you may expect.

Here’s how it works…

Your pituitary gland senses the level of thyroid hormones (T3 & T4) that the thyroid has released into the bloodstream.

The pituitary then adjusts the amount of thyroid stimulating hormone which tells your thyroid to turn on or off.

When the thyroid does not produce enough thyroid hormones, the pituitary detects this reduction in thyroid hormones, and it tries to stimulate the thyroid into action by producing and sending over more TSH.

This is the pituitary gland’s effort to return the TSH levels to “normal” and balance the thyroid’s function.

Therefore, higher TSH levels than normal suggests a thyroid that is under-active and not doing its job of producing thyroid hormone.

So, in general, higher levels of thyroid stimulating hormone equals an under-active thyroid; or hypothyroidism.

And the opposite is true.

If the thyroid is overactive and producing too much thyroid hormone, the pituitary senses that there is a thyroid hormone overload circulating through the system.

The pituitary then usually slows or shuts down thyroid stimulation, so that the thyroid will slow down its production of the T3 & T4 hormones.

This drop in TSH is the pituitary gland’s attempt to return circulating T3 & T4 hormone levels to normal.

Therefore, the TSH test results will show lower than normal TSH when the thyroid is overactive.

So, in general, lower TSH levels equals an overactive thyroid; or hyperthyroidism.

Treatment of High & Low TSH

Once your doctor has determined whether you have hypothyroidism or hyperthyroidism based on the TSH levels in the blood, treatment is usually pretty standard.

For hypothyroidism (too little), the most common treatment is a hormone replacement supplement called Levothyroxine.

This is in pill form and you simply take one a day until your system balances out.

For hyperthyroidism (too much), it is a little different.

They may use some thyroid hormone blocking drugs like Methimazole and Propylthiouracil; but the most common treatment is using radioactive iodine treatment.

What this does is actually kill some of the thyroid cells so that the thyroid does not produce an overabundance of theT3 & T4 hormones.

Don’t let the “radioactive” part scare you.

The radioactive medicine is completely gone from the body within a few days; and the majority of patients are cured using a single dose of radioactive iodine as the TSH balances out in the body.

Thyroid Stimulating Hormone Levels – They Balance Your Body & Metabolism

As you can see, a healthy thyroid and the correct, balanced TSH levels are mandatory for on overall healthy body.

You may already know this; but you also may have been confused on how exactly the working parts all come together.

If we have done our job correctly, then you now understand (in easy to follow terms) how your thyroid and thyroid stimulating hormones levels work to regulate your metabolism, and balance out your entire endocrine system.

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