T3 and T4 dosing “sweet spot”

[TheSteamboat]

Could one, in theory, supply a dosage of T3 and T4 that allows TSH to still be engaged and the body to make its own thyroid hormone? For example, if someone was on say 25mcg t3 and TSH was still in range, and they bumped to 30mcg t3 and TSH got lowered, would they potentially actually have a better metabolism with 25mcg and allowing their natural thyroid to still stay engaged?

 

[TheSteamboat]

I feel like I recall @Black Beard discussing something like this at one point

 

[Black Beard]

I feel like I recall @Black Beard discussing something like this at one point

Yeah, with low dose T4 only, but once you add T3 to T4, they have a synergistic effect on dropping TSH.


Thing is, when you take T4 only, your Free T4 can go up but your Free T3 can go down. T4 only usually leads to higher T4 to T3 ratio unless you use HGH. We all have different genetics affecting our rate of conversion, our sensitivity to TSH dropping, and even lifestyle will affect T3 conversion (low cals/low carbs/lots of cardio/being leaner = lower T3)


Taking thyroid hormones to boost metabolism kind of sucks for physique/performance purposes; it can make you flatter, increase hunger, lower endurance/strength etc. Many pros just run HGH+extra T4 and they don't touch T3.

IFBB pro @Beef_Stu_97 has a recent Q & A thread and he runs 100-200 mcg T4 year round + HGH. Zero T3.


It's best to optimize the thyroid if you're hypothyroid, otherwise, year round HGH works much better for getting and staying lean and it keeps you full too.

 

[TheSteamboat]

Yeah, with low dose T4 only, but once you add T3 to T4, they have a synergistic effect on dropping TSH.


Thing is, when you take T4 only, your Free T4 can go up but your Free T3 can go down. T4 only usually leads to higher T4 to T3 ratio unless you use HGH. We all have different genetics affecting our rate of conversion, our sensitivity to TSH dropping, and even lifestyle will affect T3 conversion (low cals/low carbs/lots of cardio/being leaner = lower T3)


Taking thyroid hormones to boost metabolism kind of sucks for physique/performance purposes; it can make you flatter, increase hunger, lower endurance/strength etc. Many pros just run HGH+extra T4 and they don't touch T3.

IFBB pro @Beef_Stu_97 has a recent Q & A thread and he runs 100-200 mcg T4 year round + HGH. Zero T3.


It's best to optimize the thyroid if you're hypothyroid, otherwise, year round HGH works much better for getting and staying lean and it keeps you full too.

Interesting, so theoretically you could take an amount of t3/t4 that is actually lower dosage, but get more out of it then a slightly higher dosage of t3/t4 that is suppressing you more?

 

[Black Beard]

Interesting, so theoretically you could take an amount of t3/t4 that is actually lower dosage, but get more out of it then a slightly higher dosage of t3/t4 that is suppressing you more?

The issue is that T3 is extra suppressive, so it can lower your endogenous production. It gets tricky when you add T3, as it will often drop your endogenous T4 and T3 production unlike low34 dose T4.

 

[nothuman]

Yeah, with low dose T4 only, but once you add T3 to T4, they have a synergistic effect on dropping TSH.


Thing is, when you take T4 only, your Free T4 can go up but your Free T3 can go down. T4 only usually leads to higher T4 to T3 ratio unless you use HGH. We all have different genetics affecting our rate of conversion, our sensitivity to TSH dropping, and even lifestyle will affect T3 conversion (low cals/low carbs/lots of cardio/being leaner = lower T3)


Taking thyroid hormones to boost metabolism kind of sucks for physique/performance purposes; it can make you flatter, increase hunger, lower endurance/strength etc. Many pros just run HGH+extra T4 and they don't touch T3.

IFBB pro @Beef_Stu_97 has a recent Q & A thread and he runs 100-200 mcg T4 year round + HGH. Zero T3.


It's best to optimize the thyroid if you're hypothyroid, otherwise, year round HGH works much better for getting and staying lean and it keeps you full too.

Not to hijack, but what dose of HGH is sufficient for the thyroid conversion benefits?

 

[nothuman]

Could one, in theory, supply a dosage of T3 and T4 that allows TSH to still be engaged and the body to make its own thyroid hormone? For example, if someone was on say 25mcg t3 and TSH was still in range, and they bumped to 30mcg t3 and TSH got lowered, would they potentially actually have a better metabolism with 25mcg and allowing their natural thyroid to still stay engaged?

I used 50mcg T3 by itself before and it wasn’t enough to fully suppress my natural TSH production. I’d imagine some people would suppress it with less.

I wouldn’t advise T3 only though. That was just a result I received during a period of self experimentation trying to fix my nasty thyroid symptoms.

 

[TheSteamboat]

I used 50mcg T3 by itself before and it wasn’t enough to fully suppress my natural TSH production. I’d imagine some people would suppress it with less.

I wouldn’t advise T3 only though. That was just a result I received during a period of self experimentation trying to fix my nasty thyroid symptoms.

I ended up settling on 30mcg t3 150mcg t4. I split my t3 dose AM and PM, and it seems to keep my TSH going doing that way vs when I took all my t3 at once actually. Feeling good on these doses personally.

 

[Black Beard]

Not to hijack, but what dose of HGH is sufficient for the thyroid conversion benefits?

T3 conversion scales with HGH dosage. Generally 3 IU and up is where you will see significant difference. 2 IU still increases conversion. This is the paper: https://pubmed.ncbi.nlm.nih.gov/7828350/


Yeah, T3 monotherapy sucks. When you do T3 only, you can still be hypothyroid in some tissues. Some cells really need T4 and prefer to convert T3 from the T4. I generally see best labs for kidney function, cholesterol, and symptom resolution in people using both together.

 

[nothuman]

T3 conversion scales with HGH dosage. Generally 3 IU and up is where you will see significant difference. 2 IU still increases conversion. This is the paper: https://pubmed.ncbi.nlm.nih.gov/7828350/


Yeah, T3 monotherapy sucks. When you do T3 only, you can still be hypothyroid in some tissues. Some cells really need T4 and prefer to convert T3 from the T4. I generally see best labs for kidney function, cholesterol, and symptom resolution in people using both together.

Interesting. This is the first time I’ve actually seen the real study showing the improved thyroid conversion. Now I am thinking of raising the HGH dose since I tend to have a high reverse T3

What makes you say 3iu will have better conversion than the 2iu used in the study? Anecdotal experience I presume?

 

[Black Beard]

Interesting. This is the first time I’ve actually seen the real study showing the improved thyroid conversion. Now I am thinking of raising the HGH dose since I tend to have a high reverse T3

What makes you say 3iu will have better conversion than the 2iu used in the study? Anecdotal experience I presume?

High RT3 is normal and expected when you take T4, especially monotherapy. It's also normal when you are leaner or exercise a lot. Being lean and exercise are "stress" and body tends to try and decrease metabolism the leaner you get for homeostasis (T3 and leptin goes down). The body diverts more T4 into RT3 instead of T3 in times of stress; injury, illness, burns, etc.


RT3 is not something to be concerned about and chasing lower RT3 numbers just tends to fuck shit up unnecessarily. RT3 does not "Block thyroid receptors" contrary to internet myth. It's a biologically inert metabolite of T4.


No, the study itself literally shows a dose dependent increase in T4 to T3 conversion, the bottom right bars. :


(The bars make it look like the medium dose is better than the higher dose but the conclusion is that it's dose dependent and i've seen the same)


"In summary, GH administration in GH-deficient adults is associated with pronounced dose dependent actions on thyroid function in terms of a stimulation of peripheral T4to T3 conversion. Since the circulating T3 levels were subnormal in these patients when not receiving GH replacement, despite T4 substitution in conventional doses and normal T4 levels, we speculate that the effects of GH on peripheral iodothyronine metabolism may be physiologically important."

 

[nothuman]

High RT3 is normal and expected when you take T4, especially monotherapy. It's also normal when you are leaner or exercise a lot. Being lean and exercise are "stress" and body tends to try and decrease metabolism the leaner you get for homeostasis (T3 and leptin goes down). The body diverts more T4 into RT3 instead of T3 in times of stress; injury, illness, burns, etc.


RT3 is not something to be concerned about and chasing lower RT3 numbers just tends to fuck shit up unnecessarily. RT3 does not "Block thyroid receptors" contrary to internet myth. It's a biologically inert metabolite of T4.


No, the study itself literally shows a dose dependent increase in T4 to T3 conversion, the bottom right bars. :


(The bars make it look like the medium dose is better than the higher dose but the conclusion is that it's dose dependent and i've seen the same)


"In summary, GH administration in GH-deficient adults is associated with pronounced dose dependent actions on thyroid function in terms of a stimulation of peripheral T4to T3 conversion. Since the circulating T3 levels were subnormal in these patients when not receiving GH replacement, despite T4 substitution in conventional doses and normal T4 levels, we speculate that the effects of GH on peripheral iodothyronine metabolism may be physiologically important."


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Sorry I wasn’t clear. My rT3 was already high without taking any T4. It was between 20-23 while Free T3 was anywhere between 2.7-2.9 depending on the blood test. I only brought it up because it appears my issue was poor conversion.

I’m aware that rT3 doesn’t block T3 from entering the nucleus. I only mentioned it because I thought it was more relevant when not using thyroid hormone.

Based off the baseline values, I wonder if 2-3iu of HGH would help. I only use 1iu now.

However, my baseline IGF before any HGH was between 300-315 depending on the blood draw, so I’m not sure.

As for my second question, I didn’t catch the dose dependent response so thanks for answering that part.

 

[nothuman]

Sorry I wasn’t clear. My rT3 was already high without taking any T4. It was between 20-23 while Free T3 was anywhere between 2.7-2.9 depending on the blood test. I only brought it up because it appears my issue was poor conversion.

I’m aware that rT3 doesn’t block T3 from entering the nucleus. I only mentioned it because I thought it was more relevant when not using thyroid hormone.

Based off the baseline values, I wonder if 2-3iu of HGH would help. I only use 1iu now.

However, my baseline IGF before any HGH was between 300-315 depending on the blood draw, so I’m not sure.

As for my second question, I didn’t catch the dose dependent response so thanks for answering that part.

I blame my thyroid symptoms on missing the dose dependent part on the link. They’re bad today

 

[Black Beard]

Sorry I wasn’t clear. My rT3 was already high without taking any T4. It was between 20-23 while Free T3 was anywhere between 2.7-2.9 depending on the blood test. I only brought it up because it appears my issue was poor conversion.

I’m aware that rT3 doesn’t block T3 from entering the nucleus. I only mentioned it because I thought it was more relevant when not using thyroid hormone.

Based off the baseline values, I wonder if 2-3iu of HGH would help. I only use 1iu now.

However, my baseline IGF before any HGH was between 300-315 depending on the blood draw, so I’m not sure.

As for my second question, I didn’t catch the dose dependent response so thanks for answering that part.

Yeah, even without taking T4, someone who is very leaner, works out a lot, etc these things can increase RT3. It's the body shifting the metabolism down for self preservation. People who do a lot of endurance training or are very lean tend to have higher RT3 and lower Free T3. This is why a lot of guys who are dieting notice a big increase in energy when they supplement T3.


What is your IGF-1 now on the 1 IU? There is something about exogenous T3 that is different than the increase you get from HGH, so you can still trial a low dose of T3 added to your T4.


Don't worry too much about those thyroid symptoms, we will get you to 100% soon.

 

[nothuman]

Yeah, even without taking T4, someone who is very leaner, works out a lot, etc these things can increase RT3. It's the body shifting the metabolism down for self preservation. People who do a lot of endurance training or are very lean tend to have higher RT3 and lower Free T3. This is why a lot of guys who are dieting notice a big increase in energy when they supplement T3.


What is your IGF-1 now on the 1 IU? There is something about exogenous T3 that is different than the increase you get from HGH, so you can still trial a low dose of T3 added to your T4.


Don't worry too much about those thyroid symptoms, we will get you to 100% soon.

Ah I didn’t know fit people had higher rT3’s! Problem is so much thyroid info online is designed for middle aged obese women so it’s hard to know what also applies to fit populations.

IGF on 1iu is 335, so it’s up a little from baseline. Do we even know whether IGF1 is the reason the HGH helped conversion? Because if it is, I shouldn’t be having an issue.

And yea,I go for stretches when I’m totally fine for a while and the symptoms just come back and destroy me, and then I don’t know whether I need more or less thyroid to feel better. It’s brutal

 

[Black Beard]

Ah I didn’t know fit people had higher rT3’s! Problem is so much thyroid info online is designed for middle aged obese women so it’s hard to know what also applies to fit populations.

IGF on 1iu is 335, so it’s up a little from baseline. Do we even know whether IGF1 is the reason the HGH helped conversion? Because if it is, I shouldn’t be having an issue.

And yea,I go for stretches when I’m totally fine for a while and the symptoms just come back and destroy me, and then I don’t know whether I need more or less thyroid to feel better. It’s brutal

I don't believe so. It's likely the HGH and not the IGF-1. HGH is a messenger as much as a hormone. The IGF-1 increase is primarily from the HGH telling the liver to produce more IGF-1.


I would get that Free T4 into the 1.4-1.7 ng/dL range and try a small dose of T3, 5-10 mcg. It is VERY potent once your Free T4 is optimal. Some people are optimal at only 5 mcg per day.

 

[nothuman]

I don't believe so. It's likely the HGH and not the IGF-1. HGH is a messenger as much as a hormone. The IGF-1 increase is primarily from the HGH telling the liver to produce more IGF-1.


I would get that Free T4 into the 1.4-1.7 ng/dL range and try a small dose of T3, 5-10 mcg. It is VERY potent once your Free T4 is optimal. Some people are optimal at only 5 mcg per day.

I re-started both the 100mcg T4 and added 6.25mcg T3 two days ago so hopefully I get some symptoms resolution again soon. It’s really the brain haze that destroys me.

I’ll try bumping the HGH I think to 2iu as well. I’ve been hesitant to raise my dose because it usually spikes my heart rate so I wonder if it’s bad for my overall health, but sometimes the heart rate seems to fall back down to normal after a while.

The other day when I took a few days off thyroid hormone, my resting heart rate dropped the lowest I’ve seen it (53), so I seem to have some room for it to go up. I felt horrible though.

 

[Black Beard]

I re-started both the 100mcg T4 and added 6.25mcg T3 two days ago so hopefully I get some symptoms resolution again soon. It’s really the brain haze that destroys me.

I’ll try bumping the HGH I think to 2iu as well. I’ve been hesitant to raise my dose because it usually spikes my heart rate so I wonder if it’s bad for my overall health, but sometimes the heart rate seems to fall back down to normal after a while.

The other day when I took a few days off thyroid hormone, my resting heart rate dropped the lowest I’ve seen it (53), so I seem to have some room for it to go up. I felt horrible though.

Are you dosing GH in the morning or night time? Sometimes the GH lethargy can mimic hypo symptoms (brain fog, lethargy, feeling off), so keep that in mind if you go up in dose.

 

[nothuman]

Are you dosing GH in the morning or night time? Sometimes the GH lethargy can mimic hypo symptoms (brain fog, lethargy, feeling off), so keep that in mind if you go up in dose.

I have been taking it before bed. I had the same symptoms even when I wasn’t using HGH though.

 

[dimethyl11]

could use some direction on my thyroid results:

Tsh 1.34 (0.35-5)
T3 5.1 (3.9-5.4)
T4 10 (11-23)

Taking 3.5iu gh, working up to 5iu

I have t4 and t3 on the way. My plan was 100mcg t4 and monitor but I could use some help