Simple Question about Constipation

Hi somebody of you have been constipated with protein? Im doing experiments and I mix 50% wpi and 50% wpc and gave to my friends and all of us are constipated? My question is : Wich protein couses that or the mix or the quantiti. We take from 15 to 25 grms from that mix. Thanks. (Sorry for my english) I'm Learning english and about protein.

Not really sure about that. I would say that is more of a personal issue as I dont ever experience that

FWIW, I am dairy intolerant and if I consume diary, one of the effects is that I do become constipated.

I did other mix but i dont remember what kind of protein i used in that mix and we did not have constipation.