Expert Advice From Louise O’Connor, Australian Naturopath + Wellness Coach { About the book }

What Causes High Reverse T3 (RT3)? {There Are 5 Key Reasons}

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what causes high reverse T3Have you been told you have high reverse T3? Please keep reading as this article answers the important question ‘what causes high reverse T3?’

Firstly, How Does High Reverse T3 Impact Your Health?

High reverse T3 has a powerful effect on slowing your metabolism.  As a consequence, excess reverse T3 pushes your body into a hypothyroid state which triggers a long list of high reverse T3 symptoms. You can learn more here: Do You Suspect You Suffer High Reverse T3 Symptoms?

What Causes High Reverse T3 (RT3)? {There are 5 Key Reasons}

+ Unrelenting physical and emotional stress

Ongoing stress and anxiety cause cortisol to soar. It’s important to realise cortisol is the hormone that helps you cope with stress. However there’s a flip side to having excessive amounts of cortisol circulating in your blood stream. Too much cortisol inhibits normal thyroid hormone activity. Overtime this leads to an excess production of reverse T3.

Health experts propose this is a protective response to slow metabolism and conserve energy during times of prolonged stress. Your body knows it simply cannot survive on high alert for too long. Over time it leads to burnout.

+ Extreme, or yo-yo dieting

Cutting calories in an effort to lose weight sparks the body’s hard wired famine response. As food becomes scarce your body feels the need to conserve energy and it achieves this by putting the brakes on your metabolic rate.

In essence, the easiest and quickest way your body can slow your metabolic rate and thereby conserve energy is to produce massive amounts of reverse T3.

+ Low iron is leaving you tired and breathless

Chronic iron deficiency is a common finding in hypothyroidism. This deficiency needs to be addressed as a lack of iron impairs proper thyroid hormone metabolism. More specifically, low iron decreases healthy conversion of thyroxine (T4) to more active triiodothyronine (T3).

Adequate levels of iron are especially important to help fight fatigue as this mineral is required by your red blood cells to carry oxygen around your body. Furthermore, when iron is low your blood oxygen levels are low and your body cannot properly utilise T3 at a cell level.

+ Long term exposure to toxins

Toxins such as heavy metals, pesticides, and industrial chemicals switch on a physical stress response. It’s widely accepted toxins have a serious effect on your thyroid health.

At a cellular level toxins can 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. These factors sabotage day to day function of your thyroid. Over time the stress of dealing with toxins and the diminishing function of the thyroid can activate far greater production of reverse T3.

+ Systemic illness is a factor

It is difficult to recover from reverse T3 dominance when a chronic underlying illness is not addressed. When your body feels under threat by a long standing illness it slows metabolism. Your body hits the ‘hibernation’ button to lessen the impact of a chronic illness.

For example, a latent viral infection may be causing widespread problems. This can lead to chronic fatigue syndrome which is often associated with over production of reverse T3. Treating excess reverse T3 secondary to a specific chronic illness is best discussed with a skilled healthcare practitioner.

What Does The Reverse T3 Blood Measure?

The reverse T3 blood test measures circulating levels of reverse T3. In fact, this is the only test that can be used to check your reverse T3 levels.

  • The reverse T3 test is normally included in a complete thyroid panel. If you wish to learn more about comprehensive testing please view this article: The Top 5 Thyroid Blood Tests. These Thyroid Tests Are Essential. Find Out Why!
  • If you are experiencing hypothyroid symptoms but your TSH, free T4, and even your free T3 appear to be normal you may want to consider checking your reverse T3.  As a matter of fact, most integrative doctors and Naturopaths now routinely perform the reverse T3 test. It’s considered essential to effectively diagnose, and manage a low thyroid disorder.

Now I would love to hear from you. Did you find this article on what causes high reverse T3 (RT3) interesting? To leave your comment, feedback or questions about this thyroid health blog post just use the comment box at the bottom of this page.

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  1. Alanyo Alice Grace says:

    I want to acknowledge you for this critical but informative news.
    The symptoms described above seems to be what I am experiencing now. Since all my investigations (exceptT3 not done), were normal, I have all along been on Lugol’s iodine, 2=3 drops per meal without any significant improvement. Instead, the swelling of the (L) thyroid is increasing and those symptoms described are there. How can I be helped?
    Secondly, What are sources of metals described above? In other words, how do we get them into our bodies?
    Thanks a lot

  2. Louise O'Connor says:

    Hi Alice, it is vital to get all five thyroid tests done as this gives you an overall assessment of what is happening with your thyroid hormones. This means getting TSH, free T4, free T3, thyroid antibodies and reverse T3. When free T3 drops below 4.5 pmol/L and reverse T3 is high it is usual to experience hypothyroid symptoms. Unfortunatley heavy metals are pervasive in our food, water and air. For many people silver amalgam dental fillings are a source of mercury. This mercury leaches from the teeth over time and enters general circulation. Your thyroid requires more than iodine. If you are in Australia please take a look at ThyroSynergy. This is a thyroid health product that I developed. It has specially formulated with 10 ingredients to aid thyroid health.

  3. susan fletcher says:

    Hi would uou have a diet plan for low thyroid function im floundering a bit thankyou

  4. Jane Crawforrd says:

    I found this helpful since my lab tests show I have high RT3. However, my ferritin is also high, not low. How does this impact the situation?

    • Louise O'Connor says:

      Hi Jane, raised ferritin is common in hypothyroidism. There’s a number of reasons why. It may not necessarily be related to high RT3 but rather the fact your free T3 is low which decreases digestive function, and other metabolic activity. Best wishes, Louise O’Connor

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