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The Impact Of GUT On Thyroid Hormone Conversion

By Lucy Rose Clinic

January 19, 2021

We often talk about the thyroid gland and it’s function when discussing thyroid health, but the majority of patients who present with symptoms, yet are not medicated, don’t have a problem with their thyroid gland. 

This leads to confusion, frustration, and inevitably searching for answers.

 Maybe that is how you found us?

There are several reasons why TSH can be normal, yet the body display all the symptoms of hypothyroidism, and today I want to talk about one big factor – our microbiome.

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If you are suffering with any of these symptoms, then read on!

  • bloating or fluid retention
  • weight gain 
  • fatigue
  • waking tired
  • feeling just not like yourself
  • shedding hair
  • weaker nails
  • muscle stiffness, cramps, or twitches
  • aching joints
Thyroid and the Microbiome

What is the microbiome?

The definition is microorganisms in a particular environment. In fact, all parts of the body have their own microbiome, but the word ‘microbiome’ has become a household name for the microbiome of the digestive tract – particularly the large bowel or colon. But it’s interesting that all body parts have a microbiome – eyes, skin, ear canal, mouth, etc. For today’s purposes, we are talking about the microbiome of the digestive tract.

What disrupts the microbiome balance?

In todays fast paced world a lot. Of note, the amount of hand sanitiser we all have to use is having an impact on our gut bacteria – the extend of this is yet to be discovered. 

One bout of anti-biotics can clear the microbiome, and many people are not instructed to repair this with probiotics after treatment, leading to a permanent shift in the gut balance.

Antibiotics are found in our food chain, and ingested in our diet without our awareness (or consent). Low dose antibiotics are fed to feedlot animals to promote faster growth, which allows for faster turnover and more profit. Most beef, pork, poultry consumed by humans contains small amounts of antibiotics. This is just one reason we recommend sourcing organic food.

Other factors that affect our diversity of gut microbes:

  • Cesarean Section. 
  • Over the counter medications such as painkillers, mouthwashes, antacids, and laxatives.
  • Artificial food colouring compounds have been found to have antibacterial and antifungal properties.   
  • Chlorinated drinking water.  
  • Surgery and medical treatments.
  • Pesticides.
  • Antibacterial soaps and shampoos.

Ways to support a healthy microbiome

  • Eat fermented foods such as sauerkraut, kefir, kombucha, yogurt.
  • Take a probiotic and change the strains regularly to increase diversity.
  • Get outside into nature. We get microbes via air too.
  • Eat lots of vegies – this feeds our gut bacteria to keep them healthy and productive.

Low thyroid hormone affects gut health. And vise versa.

If your thyroid is not working well, then all parts of the body slow down, and gut healing, digestive production and gut motility are affected. This is turn affects the diversity of the bacteria in the gut.

On the flip side, if you have low gut microbe diversity, then you can have up to 20% less active thyroid hormone conversion (Triiodothyronine).

Microbes in our gut live with us symbiotically. They need food (from our diet – called pre-biotics) and in turn release all sorts of goodness that we absorb and use, such as active T3, active B12, serotonin, GABA and much much more.

In fact, microbes release deiodinase enzymes, which converts T4 into T3. A disruption in the microbiome can have big effects on thyroid symptoms such as fatigue and weight gain.

Testing The Thyroid

Testing the thyroid comprehensively can help assess where the problem lies. It will discover if the issue is to do with the gland, the rate of thyroid hormone conversion, nutrient deficiency, or other factors.

We run the following tests to get a clearer picture than simply relying on TSH which is the standard test:

  1. TSH
  2. Free T4
  3. Free T3
  4. Reverse T3
  5. Thyroid peroxidase Ab.
  6. Thyroglobulin Ab.
  7. TRABs
  8. SHBG – sex hormone binding globulin

When you have comprehensive testing done, you can see why the thyroid symptoms are present by discovering the root cause.

↘ ↘ ↘ Patient Review ↙ ↙ ↙

“After struggling for many years with all sort of problems from allergic reactions, weight gain, extreme tiredness, bowel issues –  I am now feeling so much better. More energy and even lost 9kg. I would recommend the testing to give the answers you need.”  – B.M.

Addressing thyroid health leads to a healthy body – so book a call to discuss your health and find out how we can help!


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