Probiotics!! I can't do dairy, so I've really gone with the Kombucha Tea, and it's REALLY took care of the constipation and toxins for good it seems like! Buttermilk, if it's store baught probably will do little or no good. I did do yogart for a few days a while back, and it helped a lot, but I stopped when my Kombucha was done and went with that. (I haven't done kerfir.) The Kombucha Tea was a little hard on my stomach after the first 2 weeks, so I stopped for a while, then went every other day for a while. It's totally fine with me now, and it's absolutely amazing!