Its not exactly a balanced diet... and certainly not good for any length of time. Trouble is that I find that I can put on weight eating the amounts and types of food that I should be losing weight on, and I'm active as well - and I'm not cheating either.
1st in 1 month - breakfast 1 grapefruit (eaten as per an orange ie skinned and in segments). Apple for 11's. Lunch - salad (lots of lettuce, toms, cucumber etc) with balsamic vinegar. Pot of fat-free sugar free yoghurt. Apple/ 2 mandarins for 4's. Supper - some sort of veg dish - ie lots of veg, portion of pulses of some variety, perhaps small amount of rice. (I'm vege - you could probably substitute v. low fat meat option instead of pulses sometimes, although pulses are great for losing weight)
This is really too low on protein, calcium and carbs to do for too long, but as a kick start to a weight loss regime it is great.
CAUTION: when you start to add things to this after how ever long you do it, you need to be really sensible and not go on a blitz otherwise you'll put it all back on in no time at all.
If I want to get this off to a really good start I just have fruit for a week, but don't suggest this for any longer than that, and not everyone can do this without getting faint etc (I find myself very energised by it and am bouncing around on only 5 pieces of fruit a day which shows you my metabolism is just cockeyed).
Hope it helps, although you do need to have a good deal of motivation to do this.