Ok. I asked because when in contest prep, low calories, my IGF-1 dropped all the way down to 54. I don't remember my hgh dose right now (I can probably find it) but I think it was either 4 or 5 iu daily.
The same hgh at the same dose scored 345 a few weeks after the contest when I was eating everything in sight.
So, yeah, I believe diet affects IGF-1. I would say that is only an experiment of one, but I have had other competitors who tested during a contest prep tell me the same thing happened to them, so I tend to think that diet can greatly influence IGF-1.
Going off memory at the time my natty IGF-1 was 220 or so.
In my ignorance I kind of went after the source . . . I felt badly about that after the same hgh scored much higher after the contest. I publicly posted the results in the same source's forum to undo any damage I might have done if possible.