Fasting, T3 and rT3, and metabolism


(Judy Marriott) #1

I have a friend who is really interested in biochemistry, he raised a concern about extended fasting and thyroid function.
He thinks that the thyroid has a starvation mechanism involving T3. Quoting him “what does actually happen is the increase in rT3 as an attempt to preserve calories. It’s the true starvation mechanism. T3 converts to rT3 and it occupies the T3 receptors so T3 can’t attach, essentially lowering metabolism to preserve energy. It’s the main reason cyclic fasting is recommended.”
How much is this a concern? Does that limit the amount of time that an individual should fast for on an extended basis?


#2

I am hypothyroid, and my endo says that rT3 is simply an error in the body’s conversion of T4 to T3 and the rT3 remains inert in the body and has no effect on metabolism.

My endo studied with the scientist who discovered rT3 so I tend to believe his explanation. Since I also
thrive under his care, he has even more credibility with me.


(Judy Marriott) #3

Thank you for your input, this makes me feel much better about extending out my fasts a bit more!


(Lisa Maxey) #4

I have had high RT3 for years & low cortisol. It is the result of caffeine abuse and high stress for an extended period of time.

I think IF is better than EF for people with high RT3 to reduce the strain on adrenals.

The only reason I am hypothyroid is because RT3 (the inactive form of thyroid hormone) is plugging up T3 (active form) receptors.

Basically, it’s a chain reaction. The adrenals get whipped and burn out so cortisol eventually lowers to almost flat line, the thyroid becomes hypothyroid b/c of excess RT3, & then other hormones start to decline (progesterone, testosterone, dhea, etc).

This is the whole reason I stick with Keto. It is one of the only things I have tried that is steadily improving my cortisol, dhea, testosterone, and progesterone levels.

The RT3 is still a problem and I am still fatigued even though I’ve been strictly Keto for 8 months, but I think that if you spent years abusing your adrenal glands, it will be years fixing them.

A lot of people don’t believe your adrenals can become weakened or sluggish, but you can see the cortisol output via saliva testing through ZRT Labs or a blood test at an endocrinologist (where they give you adrenal stimulants and measure how long it takes to spike).

In the case of high RT3, KCKO & avoid caffeine and EF.


(icky) #5

Hi Lisa,

Thanks for this info! This sounds a lot like me :see_no_evil:

I just recently got told off at the Dr’s for too high rT3 and too low T3 and I’ve had problems with cortisol and adrenals for years.

I’ve never seen the connections explained as well as you just did tho!

Can you point me towards some useful reading material regarding this stuff?

(I mean, there’s plenty of reading material out there - it’s finding the useful stuff that can be difficult…)

Thanks :blush:


(Lisa Maxey) #6

No problem!

And, I’m my experience I have yet to lose much weight on Keto as my low cortisol/high RT3 keeps my energy low and metabolism sluggish.

Here are several websites I use:

https://custommedicine.com.au/health-articles/reverse-t3-dominance/

Also, no cardio, sugar, & preferably no caffeine (I still do Keto Matcha) or alcohol.

Slow, steady workouts like yoga, walking, swimming, or anything that makes you feel happy & not stressed out.

I used to (in addition to being high strung & a espresso fiend) do interval training, spin, ect.
That only jacked up my metabolism, hormones, thyroid, and adrenals worse.

I’d also like to note that I am 34 years old, and have menopausal levels of hormones for at least 3 years documented, but I am suspicious that this has gone on for a decade.


(Shayne) #7

I also have high RT3 and Hashimotos. My four point saliva cortisol test was perfect, so I’m not suffering from any kind of adrenal issues - I thought I was but it turns out it’s all thyroid. I take T3 (felt better within three days of starting it) and my doctor specifically told me to do EF - at least four days at a time.


(icky) #8

Hi Lisa,

I read that article recently, but it was good to read it again. I should look at Marcelle Pick “Is it me or my adrenals?” again. It’s sitting in my bookshelf, but I guess it’s not doing much good there :wink:

I was thinking about your post today and started wondering about whether the coffee thing is a chicken-and-egg thing.

Surely anyone who’s experiencing the first subtle signs of adrenal fatigue and hypothyroid would be feeling that general sluggishness that makes everyone think “I know, I’ll have a coffee”.

So I wonder whether you drinking lots of coffee was just you instinctively trying to self-medicate the “sluggishness” and “tiredness”?

I’m not sure you really did much damage with the coffee, other than maybe masking the sluggishness symptoms, which would have had you seeing your Dr for blood tests sooner.

Also, the coffee may have contributed to you just pushing yourself further and maintaining a high-stress, high-cortisol lifestyle.

I know I grab a coffee, when I should probably having slightly more thyroid me… :see_no_evil::stuck_out_tongue_closed_eyes:

Do you take any meds/ supplements for your cortisol issues?

What did your Dr call your cortisol issues? Does it have a name? Or is it just classed vaguely as “adrenal fatigue”?


(Lisa Maxey) #9

Wow! That’s really interesting that you would have high RT3 & not adrenal issues.
Must be the Hasimotos causing a inflamed immune response in your thyroid.
That peaks my curiosity on why your doc would do EF for your thyroid probs.
Does it clear out RT3 to EF?
I know I’m not able to EF much yet since my cortisol is low, but maybe once that heals up I can!


(Lisa Maxey) #10

I take loads of supplements for my adrenals & am currently on progesterone cream & Armour Thyroid and additional T3 only prescriptions.
I am taking virtually every adapotegm, amino, and vitamin/mineral meant to heal adrenals & make thyroids function properly.
The only one I’m not taking anymore is an adrenal glandular, which made me feel less tired, but also gave me bad side effects (heart palpitations, hair loss, gi issues).
I felt like messing with “natural steroids” was maybe a get there quicker scheme. Every time I’ve tried to get better quickly or lose weight quickly or anything it’s blown up in my face.
I’m doing Keto, taking a lot of adaptogens, vitamins/minerals, thyroid meds, progesterone cream, acupuncture, mindfulness meditation, counseling, and learning to chill.
I believe my childhood environment, lifestyle and mindset got my adrenals in dire straights, and now it’s going to take time and patience to allow them to heal.
Luckily, Keto has done nothing, but help slowly boost my hormones.
So, I’m KCKO


(Lisa Maxey) #11

He called it adrenal fatigue. :frowning:


(Shayne) #12

He wants me to do EF for the immune system reset that studies indicate happens after at least three days.


(Karen) #13

Is T3 by prescription. Can’t find it. I can find support suppliment, all of which I am already taking.

K


(icky) #14

(Karen) #15

Cytomel is synthetic. It has some side effects too. Hmmm I’ll ask Dr about it.

K