Here’s What You Need To Know About Reverse T3 Dominance


If you’ve been told your thyroid test results are ‘normal’ you may want to learn more about reverse T3 dominance which can trigger a long list of hypothyroid symptoms.

Here’s what you need to know about reverse T3 dominance, and how to get tested properly.

Firstly, Let’s Do A Quick Recap Of Your Thyroid Hormones

Before we take a closer look at reverse T3 dominance let’s do a quick recap of your thyroid hormones.

As you may already know, a healthy thyroid produces two key thyroid hormones; triiodothyronine (T3) and thyroxine (T4). T4 is widely regarded as the ‘storage’ thyroid hormone. While T4 does have some effects, it’s only when it’s converted through to ACTIVE T3 that you really notice a difference to how you feel.

The reason?

T3 is far more potent than T4. In fact, T3 is the #1 thyroid hormone that keeps your metabolism humming.

Why Reverse T3 Is Produced

Your body converts T4 to the more active T3 by removing one iodine molecule from T4. Put simply, the 4 represents the number of iodine molecules contained within the thyroid hormone. Once one iodine molecule is removed this T4 becomes T3.

It’s important to know T3 easily locks onto the thyroid receptors located throughout your body. In effect, T3 has the greatest potential to generate energy at a cell level.

Generally T4 converts through to T3 with no trouble. This conversion takes place in response to the demand for more T3.

However, while T4 is converted to T3 it’s also possible for the T4 to get converted to an INACTIVE form of T3 known as ‘reverse T3’, or RT3 for short. As you can imagine, RT3 has the opposite effects of T3.

WHY does the body produce both ACTIVE T3 and INACTIVE RT3?

You see, maintaining an optimal metabolic rate is an ongoing balancing act. When the body wants to fire up metabolism it produces more T3. On the flip side, it uses RT3 to put the brake on metabolism. The body also produces greater amounts of RT3 as a protective mechanism during times of stress and illness.

When RT3 is not required the body quickly clears this hormone. However, problems arise when RT3 builds up in the blood and starts to pool. Over time, too much RT3 leads to ‘reverse T3 dominance’.

What You Need To Know About Testing For Reverse T3 Dominance

Unfortunately testing RT3 remains controversial. For that matter, you may even find some doctors refuse to authorize this test. If you are struggling to get proper testing there’s an alternative…order the tests you need online.

In Australia?

i-screen, Australia make it easy to order a Reverse T3 Check. No doctor referral is necessary. It’s possible to order online and get results sent directly to you. Click here to find out more: Order your Reverse T3 Check today!

In the USA?

Take back control and order the tests you need with True Health Labs. This company offer the Complete Thyroid Test Panel to give you deeper insights into the complexity of your thyroid health. The Complete Thyroid Test Panel includes the RT3 test. You can go to the True Health Labs website for more information: Order the thyroid tests you need today!

What Is A Healthy Reverse T3 Result?

The current healthy reference range for reverse T3 is 170-450 pmol/L.

If your reverse T3 is above 450 pmol/L it’s likely you will be told you have ‘reverse T3 dominance’.

Once you have your blood test results you can also go ahead and check your free T3 levels, even calculate your T3/reverse T3 ratio. When RT3 is elevated, T3 and T4 may still appear to be within the normal range. However, this is not always the case. It’s more likely you will see high RT3 associated with a sub-optimal level of free T3.


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