The Top Five Reasons Why Your Body Creates Excess Reverse T3

Reverse T3 is the ‘hibernation hormone’ as too much of this thyroid hormone triggers hypothyroid symptoms.

These symptoms can include ongoing fatigue, depressed mood, hair loss, muscle weakness, low blood pressure, a slower than normal pulse rate, and other signs of slow metabolism.

The Top Five Reasons Why Your Body Creates Excess Reverse T3

Has testing revealed high levels of reverse T3 and you are wondering WHY?

As a Naturopath with a special interest in reverse T3 disorders I have identified these top five reasons why your body creates excess reverse T3.

Let me explain more.

1. Unrelenting physical and emotional stress.

Too much stress causes cortisol to soar. This is a normal response as cortisol is the body’s major stress hormone that plays a key role in helping you cope with stress.

However there is a flip side. Soaring cortisol inhibits normal thyroid hormone activity. And over time, this leads to an excess amount of reverse T3 being produced.

Health experts propose this is a protective response to slow metabolism as this helps conserve energy during times of prolonged stress. The fact is, your body cannot survive on high alert for too long.

2. Extreme, or yo-yo dieting.

Cutting calories in an effort to lose weight sets off the body’s hard wired famine response. The body conserves energy when food becomes scarce and it achieves this by putting the brakes on the metabolic rate.

The easiest and quickest way your body can slow your metabolic rate, and thereby conserve energy is by producing a massive amount of reverse T3.

3. Systemic illness is a factor.

It may be difficult to recover from reverse T3 disorder if a chronic underlying illness is not addressed.

When your body feels under threat by a long standing illness the metabolic rate slows in an attempt to lessen the possible negative effects of the illness. However your whole body slows down as a consequence and you experience this as ongoing fatigue.

As an example, chronic active viral infections are very common and can trigger excess production of reverse T3. Long term infections also create widespread inflammation within the body and chronic fatigue syndrome.

It’s an important point…reverse T3 disorders and low T3 syndrome are often associated with long standing infections.

4. Long term exposure to toxins.

Toxins such as heavy metals, pesticides, and industrial chemicals switch on a physical stress response.

Environmental toxins also have serious effects on thyroid function. At a cellular level toxins block the thyroid cell receptors so the thyroid hormones cannot perform their job, and toxins can enter the thyroid causing damage to the actual thyroid tissue which then sabotages day to day function.

Over time the stress of dealing with toxins and loss of function of the thyroid gland can lead to greater production of reverse T3.

5. Low iron is leaving you tired and breathless.

Chronic iron deficiency is commonly associated with hypothyroidism. A deficiency should be treated with an iron supplement as a lack of iron impairs proper thyroid hormone metabolism.

More specifically, low iron decreases the efficient conversion of thyroxine (T4) to triiodothyronine T3.

Adequate levels of iron are also important to treat fatigue. This mineral is required by your red blood cells to carry oxygen around your body. When iron is low less oxygen is getting to the body which causes weakness and fatigue.

It’s important to know the ferritin blood test is the best way to test for a potential iron deficiency.

Should You Test Reverse T3?

YES! Running this lab test is essential to effectively diagnose, and manage a thyroid disorder.

As mentioned above, the reverse T3 (RT3) test measures the amount of reverse T3 in circulation. It’s critical to understanding a hypothyroid disoroder. It’s the reason it’s one of the top 5 thyroid blood tests that you should get done.

There’s no doubt comprehensive testing eliminates guesswork, and provides invaluable insights into WHY you don’t feel right.

Unfortunately testing RT3 remains controversial. For that matter, you may even find some doctors refuse to run this test. If you are finding it difficult to get the tests you want there is 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!

Please note: This post contains affiliate links, to find out more about my affiliate policy please refer to my Terms of Service.


Ruiz-Nunez B, Tarasse R, Vogelaar EF, Janneke Dijck-Brouwer DA, Muskiet FAJ. Higher Prevalence of “Low T3 Syndrome” in Patients With Chronic Fatigue Syndrome: A Case-Control Study. Front Endocrinol (Lausanne). 2018;9:97. Published 2018 Mar 20.

Moura Neto A, Zantut-Wittmann DE. Abnormalities of Thyroid Hormone Metabolism during Systemic Illness: The Low T3 Syndrome in Different Clinical Settings. Int J Endocrinol. 2016; 2016: 2157583. PubMed

Kjellman BF, Ljunggren JG, Beck-Friis J, Wetterberg L. Reverse T3 levels in affective disorders. Psychiatry Res. 1983 Sep;10(1):1-9. PubMed

Medline Plus. Ferritin Blood Test. Updated 28 January 2019. Link


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