No correlation what so ever. I find that if I haven't been on GH for awhile, I am more likely to suffer some CT issues or elbow pain within a couple months. But I have used cheaper generics and felt sides. Then switched to Nap's Hyge at the same dose and gotten no sides. Yet had lab work to show that they were working well. I think that sometimes, it's the binders that cause issues. It may have nothing to do with quality of the actual GH, but to the reaction to the binders. This is a total bro-science answer though. I have no way to know for sure!! But like anything, side effects are not the actual effect ;) gotta keep that in mind. So many guys think that they need to "feel" things in order to know they are working!