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Elevated IGF-1 Levels

Just before I started TRT, it was the first time I tested IGF-1 and it was just above range - 252ng/ml(44-280). The TRT specialist from USA that I consulted said it is totally fine. The thing is I’ve been on caber for several months and later I found reports that caber can elevate it significantly. But I’ve been also on metformin, which should reduce it. The doctor did not explain why it was fine.

3 months after starting TRT it has further increased to 280ng/ml which I guess is expected. We also made a consultation and he said it is OK. I decided to test it again today, result will be ready in a couple of days.

I read studies that high IGF-1 can cause sleeping cancer cells to grow and puts patients at a risk for developing cancer. I also did not understand whether a cancer under development can cause elevated IGF-1. And in fact I have no evidence mine is elevated from the cabergoline because I havent tested it before starting caber.

Should I be worried about this IGF-1 and what further tests should I take to check If Im at a risk?

I know some optimization doctors that put their patients on GH even chase IGF-1 of 300 and many of them consider elevated IGF-1 above range to be a good thing. So the topic is very confusing to me…

vonko, I have probably seen some of the same studies as you. It seems low is not good, and high is not good with the optimal level thought to be around 175.

How much protein do you consume?

Lance Armstrong has said the only season he took HGH was just before he was diagnosed with testicular cancer, fwiw.

I consume around 140-150g, though dont measure it, but does that affects it?

I’m jealous.

I had my baseline IGF1 tested and it was 135 (slightly below normal for my age). I then started taking MK-677 and within 2 weeks a bunch of old chronic nagging injuries disappeared. My next labs showed that my IGF1 was now 195.

However, followup labs has my IFG1 dropping to near original baseline. My doc speculates that my original purchase of MK-677 was good, and that they’ve been sending me bunk afterwards. He said it happens.

And yes, most of my aches and injuries started reappearing. So I envy you having high IGF1. The upper normal lab range my lab uses is 317. So either way, you’re upper normal which I would think is optimal.

Thank you for your opinion, it is very reassuring.
I also thought the lab ranges for IGF-1 may be flawed like the testosterone lab ranges but could not find any info. Is this 317 upper limit in ng/ml as well?

I know high normal IGF-1 has many benefits. But Im a bit worried not to put myself at risk of cancer. Also Im a bit worried whether elevated IGF-1 cannot be CAUSED by already developing cancer? Is the relationship only one way? At the end Im not sure whether in my case it is caused by cabergoline. There are a few studies showing cabergoline raising IGF-1 and it is only my guess that is the case with me.

Yes, the upper limit of 317 is in ng/ml.

Also, I am on caber too, so for me it hasn’t seemed to help raise my IGF1. I’ve only read a few studies regarding caber and increased IGF1, and they were based on people with adenomas, prolactinomas, acromegaly etc…I never read anything on its behavior in healthy individuals.

There are no such studies I guess.
Unfortunately I havent tested it before caber

High protein and high glycemic index diets can increase IGF-1.

Although my diet is definetely not perfect or “clean” it is very balanced in macros and for sure Im not overeating proteins

Yes, I don’t think diet is an issue for you.

I’m not sure I would worry about it if I am you. There are a lot of men and women out there taking hGH, even in supraphysiologic doses, slightly, not too crazy, and seem to be doing very well. Think of some of the celebrities.

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Well my worry is a bit from not knowing know about the IGF matter while reading it increases risk of cancer, not knowing from what is this caused in my case and not being sure whether an ongoing cancer can cause elevated IGF-1

I understand. You’re speaking of an carcinoid tumor, very rare. Your levels are not crazy.

By the way I speak to an endocrinologist who said the lab should have levels by age, yet the lab I use has only one reference range. So if this reference range is mean considering Im 31 maybe my levels are not so high?

I hope today will come out the latest result I tested the day before yesterday

The new result came out, a little lower but still above the range:

IGF I S ! 276.20 ng/ml 82 - 244 CLIA

Quest uses these, but they are not referenced on the lab report. The Z-Score is and is determined by the IGF-1 level and age.

Adult (ng/mL)
18-19.9 Years 108-548
20-24.9 Years 83-456
25-29.9 Years 63-373
30-39.9 Years 53-331
40-49.9 Years 52-328
50-59.9 Years 50-317
60-69.9 Years 41-279
70-79.9 Years 34-245
>80 Years 34-246
Z-Score (Male) -2.0 - +2.0 SD
Z-Score (Female) -2.0 - +2.0 SD

Here is a sample report. This is a 46y/o woman. As you can see, her Z-Score places her slightly below the mean for her age.

Thans. Here I also found a table according to which Im in range. So I guess I should just continue to enjoy the benefits of this IGF-1 level?

I have a question for you. What is your experience with patients’ IGF-1 levels and cabergoline?

I thought it should raise it, but the endo told me that caber is supposed to even lower IGF-1 as a treatment for acromegaly… Which means my IGF-1 is slightly higher due to other reason.

Not much, I don’t manage those needing cabergoline, they are sent to neurology. I have a few who came with a history of large adenoma/prolactinoma, levels were 200-300 and tumors as large as a tennis ball in one. Their hormones are shot, very low and while medical treatment brought prolactin down to the 30s and decreased the tumor, the other hormones did not recover. IGF-1 remained low. So, while they were on cabergoline when presenting and I do not know the IGF-1 levels initially, their IGF-1 levels did not seem to have responded over time.

Of those with microadenoma, diagnosed by MRI after initial bloodwork revealed elevated prolactin, no treatment was needed. We’re giving them TRT and watching.