Is the 48 hour hollywood diet (drink) unhealthy?

Better idea: Anything offering to "detoxify" you is a scam. You'll become thin and physically fit long-term when, and only when, you change your ideas about food (it's fuel, not comfort or entertainment) and make physical aerobic exercise a habit that defines you and your lifestyle. Get with a bunch of real fitness people for friendship and enjoyable times -- rather than drinking something disgusting.