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Weight Gain via Reverse T3 and Cortisol

By Lucy Rose Clinic

December 17, 2020

There is a very fine line between too much stress and not enough. And when you have too much, it throws out our thyroid, affects our weight – especially belly fat – and leads to very low energy.

Lets see why this happens in todays article.

What Are The Adrenals?

Our adrenal glands are little organs that sit atop our kidneys and are responsible for producing all of our stress hormones, such as epinephrine (adrenaline), and cortisol. In times of stress, our body switches on our sympathetic nervous system, triggering a ‘fight or flight’ response. 

Our adrenal glands are quick to respond with a shot-gun release of cortisol, allowing us to think quick and act fast. This is a normal, healthy response, but unfortunately in the lives we lead in 2020, there are far too many situations that trigger this ‘fight or flight’ response – redundancy, being stuck in lockdown with your teenage children or husband who can not seem to understand how to unpack a dishwasher. All of these stressors build up and the release of cortisol into our blood stream reaches new, sustained heights.

What does all this have to do with thyroid function you may ask? Well, a lot actually! Our body has an innate protection mechanism whereby on the perception of stress, it chooses to conserve energy to rest, relax and heal from these stressors. It does this by converting our INACTIVE thyroid hormone T4 (thyroxine – the same structure as the medication), into another INACTIVE hormone called Reverse T3 (RT3), where normally it would be converted into our ACTIVE thyroid hormone, T3. This essentially shuts down thyroid function. Now this would be helpful if we actually hibernated like bears, or at least took a few days off to recover, but we don’t. We just keep working, keep cleaning, keep dealing with the overbearing in-laws and angsty teens. And so this is how stress and cortisol negatively impacts our thyroid function.

This is actually quite easy to pick up if you know what you’re looking for, but most general practitioners don’t. Reverse T3 is a blood test we do on all of our patients.  Even if your TSH, T3, and T4 are perfect, even by our standards, unless you see RT3 you are not seeing what really is going on. If RT3 is high, it floods the cells and takes up all the receptor sites where ACTIVE T3 should be connecting, meaning the active hormone can’t get into the building because someone is in their parking space. 

RT3 is not tested in general practice and is not covered by Medicare, meaning this stress induced hypothyroidism is COMPLETELY MISSED.

Cortisol levels are commonly tested which is great. However, serum cortisol (in a blood test) is what is often used, which only shows the TOTAL cortisol in the system. It does not show you what FREE cortisol is available. A lot of our cortisol is bound up and unavailable for use, so serum cortisol is not a clear picture of what is actually going on. The serum cortisol is taken in the morning often, and can give you a vague snapshot of what is going on right then. However, what about the rest of the day? Do you peak late in the night? Does stress hit you in the afternoon? Are you exhausted by dinner time? 

Because your cortisol levels fluctuate throughout the day, we test levels using saliva for accuracy, morning, noon and night. In combination with the observance of Reverse T3 levels, it is this kind of thorough investigation which will truly shed light on thyroid function, and the extent that our stress and adrenal function is having upon it. This is what we want to know – the UNDERLYING cause. 

Do you have thyroid dysfunction? 

Do you know WHY? 

Is it from autoimmunity, nutritional deficiencies, or STRESS? Once we know the underlying cause, we can get straight to the point and treat the WHY instead of the WHAT.

If you are ready for a truly holistic health approach, suffer from fatigue, can’t budge excess weight, or struggle with any other health symptoms, book a call and see how we can help.

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