IGF1 - Zscore Results

[S1L3NC3D]

Background - Male early 50s
First time taking rHGH
Goal: long term benefits
Natural IGF1 test score:
IGF1 206. Zscore 0.9

Started for 1 month at 2iu , then past 2 weeks at a total of 3iu. Tested last week , results posted below..

Im past my reference range on both, but to my understanding , thanks to @Ghouls informative posts, what matters if im correct in reading his post is keeping Z Score below 3.

If this is the proper way to gauge this, should I stay where im at? Or should I add more to hit the max range of Z Score of 3?

Any advice is appreciated.

 

[Ateam2023]

Background - Male early 50s
First time taking rHGH
Goal: long term benefits
Natural IGF1 test score:
IGF1 206. Zscore 0.9

Started for 1 month at 2iu , then past 2 weeks at a total of 3iu. Tested last week , results posted below..

Im past my reference range on both, but to my understanding , thanks to @Ghouls informative posts, what matters if im correct in reading his post is keeping Z Score below 3.

If this is the proper way to gauge this, should I stay where im at? Or should I add more to hit the max range of Z Score of 3?

Any advice is appreciated.

Imo , I think that's a very good IGF1 score for a 50+ year-old , i also fall into that category of 50+, you could push the envelope, "but why", when you are at a optimized level and a very good one at that, why risk the potential side effects that come with having IGF-I too high. I would ride out your current protocol and retest in another six weeks to see if you're maintaining that superb IGF1... then you'll know if you are at a stable dosing protocol,

 

[Nighthawlk]

If your goals are to avoid acromegaly, you want to keep it under 3. It looks like you have a little room to spare but is it worth paying for another blood test? Your IGF-1 looks very good on 3iu. Maybe just keep it where it is?

I am mid-40s taking 4iu. I got bloods yesterday and waiting on results. If I am under 3 but as close as you are, I am planning to keep the dose the same. Close enough in my book and much better than not taking it. Your IGF-1 is like you are in your mid-20s.

 

[S1L3NC3D]

Thanks for your advice. I was on the same train of thought, but since I have little experience with this I just needed a sounding board. @Ateam2023 and @Nighthawlk - thank you !

I will retest in a month. As of now, no side effects as far as CTS. Just overall concerned not to overdue it and risk long term health issues.

I will report back to this thread in about 1.5 months once testing comes back. Ill be doing another full panel test as my creatinine and eGFR are out of refernece range also. I was also running Test C @250 week, NPP @75mg week, and Mast P @150mg week. So I am assumiong this could have effected it. I have since dropped both the NPP and Mast and lowered my TestC down to 175mg week to cruise for a while
*Creatine 1.44
*eGFR 58

 

[S1L3NC3D]

Test Results

 

[johnjay06]

Test Results

Do you supplement creatine, and did you workout prior to the test? Those can skew the results. Have you ever had EGFR test prior to this one to have a reference?

 

[Ateam2023]

Thanks for your advice. I was on the same train of thought, but since I have little experience with this I just needed a sounding board. @Ateam2023 and @Nighthawlk - thank you !

I will retest in a month. As of now, no side effects as far as CTS. Just overall concerned not to overdue it and risk long term health issues.

I will report back to this thread in about 1.5 months once testing comes back. Ill be doing another full panel test as my creatinine and eGFR are out of refernece range also. I was also running Test C @250 week, NPP @75mg week, and Mast P @150mg week. So I am assumiong this could have effected it. I have since dropped both the NPP and Mast and lowered my TestC down to 175mg week to cruise for a while
*Creatine 1.44
*eGFR 58

Get that EGFR under control man, , "advice that was given to me when I had skewed numbers, just like you " was toGet a "Cystatin c " test that will give you a better picture of kidney health etc, thank you @Sampei for that recommendation, that's how I found out that I had stage 3A CKD , which is totally treatable, and thankfully, I caught it early

 

[fit2beking]

Test Results

Get that EGFR under control man, , "advice that was given to me when I had skewed numbers, just like you " was toGet a "Cystatin c " test that will give you a better picture of kidney health etc, thank you @Sampei for that recommendation, that's how I found out that I had stage 3A CKD , which is totally treatable, and thankfully, I caught it early

Look into Astragalus and Cordyceps-M. This should help.

 

[Photon]

If your goals are to avoid acromegaly, you want to keep it under 3. It looks like you have a little room to spare but is it worth paying for another blood test?

It's a pretty cheap test in the US.
30 max.
15 of you have a Fitomics sub..

 

[Ateam2023]

So Here my ridiculous z score (for my age) when running 5 ius and eating in a "slight" surplus and on a small bulk of 750 ish mg total AAS load per week, , this was in June 2025, i have since lowered my Igf1 and z score to a more appropriate number,

 

[Ghoul]

Background - Male early 50s
First time taking rHGH
Goal: long term benefits
Natural IGF1 test score:
IGF1 206. Zscore 0.9

Started for 1 month at 2iu , then past 2 weeks at a total of 3iu. Tested last week , results posted below..

Im past my reference range on both, but to my understanding , thanks to @Ghouls informative posts, what matters if im correct in reading his post is keeping Z Score below 3.

If this is the proper way to gauge this, should I stay where im at? Or should I add more to hit the max range of Z Score of 3?

Any advice is appreciated.

I’d leave things as they are, with a little buffer under 3, particularly since you’re using Quest.

Quest used LC/MS for IGF-1.

It’s very selective and only counts “wild type”, ie “normal” IGF-1 molecules.

The other types of tests, ie, labcorp, include a bunch of “mutant forms” of IGF-1 in the total count. Some of those are inactive trash, but some are active, often just weaker than regular IGF-1 or have a shorter half life.

So Labcorp (and pretty much everyone else but Quest) errs on the side of (probably slightly) overestimating active IGF, and therefore risk.

Quest on the other hand may underestimate risk by not counting weak but active isoforms of IGF.

It’s no big deal if you’re on Labcorp thinking you’re Z 2.9, but really only 2.6, vs Quest, thinking you’re 2.9 but really 3.6, for example.

There’s only a small chance of the later, and in the vast majority of cases Quest is much more accurate, but since this is about long term safety, especially when considering “riding the edge” with Z up to 3, I think a small buffer with Quest is the way to go. Of course you could always get a test done at Labcorp to compare and see if you have lots of isoforms.

 

[Photon]

I’d leave things as they are, with a little buffer under 3, particularly since you’re using Quest.

Quest used LC/MS for IGF-1.

It’s very selective and only counts “wild type”, ie “normal” IGF-1 molecules.

The other types of tests, ie, labcorp, include a bunch of “mutant forms” of IGF-1 in the total count. Some of those are inactive trash, but some are active, often just weaker than regular IGF-1 or have a shorter half life.

So Labcorp (and pretty much everyone else but Quest) errs on the side of (probably slightly) overestimating active IGF, and therefore risk.

Quest on the other hand may underestimate risk by not counting weak but active isoforms of IGF.

It’s no big deal if you’re on Labcorp thinking you’re Z 2.9, but really only 2.6, vs Quest, thinking you’re 2.9 but really 3.6, for example.

There’s only a small chance of the later, and in the vast majority of cases Quest is much more accurate, but since this is about long term safety, especially when considering “riding the edge” with Z up to 3, I think a small buffer with Quest is the way to go. Of course you could always get a test done at Labcorp to compare and see if you have lots of isoforms.

So the limit is higher with LC

 

[Ghoul]

So the limit is higher with LC

Definately ok to “ride the line” at 3 because you won’t go over. But you could be way under and not realize it.

Endocrinologists switch to Quest when IGF looks good but the patient still has “low IGF symptoms”, because on Quest, IGF will be low, and there will be a note about high amount amounts of IGF-1 variants detected but not counted in the IGF-1 measurement or Z-score”.

Labcorp can’t tell the difference between inactive or Active variants and normal IGF. It may miss some variants entirely (so it’s possible with Labcorp you could unknowingly have excessively high IGF too if those variants are active, but this is very unlikely).

 

[S1L3NC3D]

Do you supplement creatine, and did you workout prior to the test? Those can skew the results. Have you ever had EGFR test prior to this one to have a reference?

I did a full panel before starting anything besides running TRT Test C at 140mg a week. Put my test a little above 900.

I do not take creatine, and I did not work out 48 hours before test as I read i could effect certain outcomes of the test.

Attached is my before results.

 

[S1L3NC3D]

Get that EGFR under control man, , "advice that was given to me when I had skewed numbers, just like you " was toGet a "Cystatin c " test that will give you a better picture of kidney health etc, thank you @Sampei for that recommendation, that's how I found out that I had stage 3A CKD , which is totally treatable, and thankfully, I caught it early

Will do. Thanks for the advise. It the original level I posted above , does it look to be an issue ?

I know the on cycle results look bad and I did read abou lt the 3A CKD. Kind of scared me. Im hoping coming of the NPP and Mast and just running TRT at 140mg and rHGH at 3ius will resolve this. I will retest of course in about 1.5 months. What's your thoughts on this ?

 

[Elektrobot]

I did a full panel

What does full panel mean to you?

It might mean something different to others.

If you didn't check cystatin-c, then in the context of what we are doing here, it wasn't a full panel.

** I just saw your post about coming off npp and mast

Did you do a lipid panel, apob, lpa, thyroid panel, cystatin-c, ggt....

 

[S1L3NC3D]

I’d leave things as they are, with a little buffer under 3, particularly since you’re using Quest.

Quest used LC/MS for IGF-1.

Makes sense . Thank you for this perspective.. I didnt realize the test were so different.

I will take everyone's advice here and stay where Im at.

I will also take your advice and test at Lapcorp. I just wasn't sure Labcorp added in the Z Score with the IGF1 test. I knew Labcorp did , thats why i selected them . That being said i will schedule a test for next week .

 

[S1L3NC3D]

What does full panel mean to you?

It might mean something different to others.

If you didn't check cystatin-c, then in the context of what we are doing here, it wasn't a full panel.

** I just saw your post about coming off npp and mast

Did you do a lipid panel, apob, lpa, thyroid panel, cystatin-c, ggt....

I had my Primary Dr pull bloods and urine. Asked him to pull a full panel. Hes not very liberal about AAS and rHGH, so I don't say anything to him.

Here's the test he ordered. This was before I started the cycle , and was only running TRT.

 

[Elektrobot]

I had my Primary Dr pull bloods and urine. Asked him to pull a full panel. Hes not very liberal about AAS and rHGH, so I don't say anything to him.

Here's the test he ordered. This was before I started the cycle , and was only running TRT.

For general health he hit most of the things, but like others have said, a cystatin c test would probably be good to get after seeing your other numbers.

What did your lipid panel come back looking like?