Juice fasting I don't think would be along the same lines as juices have many carbs in them that we do not digest well, but feed the bacteria you are trying to starve out really well. Vivonex has carbs in it (the juices also won't provide the protein in it) but they look like ones that you should digest completely (made up of all glucose). It doesn't have fructose or sorbitol which would be in a lot of the fruit juices. Some veggies also have fructose, and again you aren't likely to get the balanced protein you need.You really do need to get breath testing if you can. I know at the GI clinic I go to they do breath testing and have found that some people who the doctors are sure must have SIBO based on symptoms really don't. It is hard to diagnose strictly on your symptoms.