6 month physician supervised diet/ZONE DIET

today was my first appointment...EVER.
i was put on my 6 month pre op physician supervised diet.
1200 calories...40% carb 30%protein 30% fat...the doc said...just follow the zone diet.
ok, i thought. heard of it...i'll look it up later.
so i look it up..HUH? what is this crap?? lol
anyone ever done this? heard of it? ideas?