Is there a safe way to completely empty my intestine/colon?

My problem is that it takes food 5 days to pass through my system. I am now regular and have a couple BM's everyday due to eating more fiber, less junk food, more water, more exercise, less caffeine and alcohol. But I have about 5 days worth of food in my intestine/colon at any given time and I know this is not healthy. Is there a safe way to flush most of this out so I can keep eating right and exercising and hopefully the meals after this flushing will come through my system in less than 5 days? Or is my digestive system really messed up and will continue to process things at such a slow pace? Having this much food in me, always makes me feel full and like I have to make another BM even after I just went. I also have a lot of gas at times and bloating, and other IBS symptoms. My doctors are idiots and dont know jack. They just tell me to eat more fiber and I'll be magically cured. Tweet