Intermittent fasting works just as well, and it’s maintainable. Eat during an 8-hour windows and only drink water tea or coffee during the rest of the day. It will reset your metabolism in a short period. Look at www1percentedge for an easy science-based diet. Add in a simple 5x5 weight lifting program, and you’ll see incredible results even if you do no cardio.
I can’t speak for short-term fasting, other than to say that people will not get into Ketosis with it, as several consecutive days of 100% fasting (water only) is needed.
But then again, if it works for some people, so much the better.