I don't think the acid is from the supplements. It's a genuine detox symptom, for sure. I think it may have something to do with the body eliminating acidosis (pH imbalance). The body may be using the stomach as a "dumping ground" for acid because it knows the stomach can handle it, considering it's designed to be acidic most of the time. But, this is just a theory. I am reading this forum to help find an answer as to what exactly the heartburn is all about. I have also had lower back pain. And the past few days I had a boil on my arm that slowly got bigger until it was the size of a quarter, but last night, probably one of the worst nights of my life, I suffered from ungodly heartburn. I passed some solid waste and it suddenly went away, and now I notice the boil has almost disappeared. Strange.