I think moderate fasting will clear up your skin thing. That does sound toxic, though that does not necessarily mean you have buildup in your colon! Sounds more liver-related... have you done any liver flushing? Great forum here at curezone with all the info.
Once you are done flushing yourself out with juice, go back to that cleansing/rebuilding diet with extra fiber. After a week or so, maybe try a liver flush.