The best diet is the one you stick to but really its all about a lifestyle change, you have to be able to eat like this for the rest of your life.
I have been reading a lot of forums/info in the net about diets/eating healthy and have found a lot of info I am using now in my everday life. At the moment I am using a 40/30/40 plan being 40% of my calories come from carbs 30% from fat 40% from protein. a good way of tracking this is on fitday.com (free) it breaks it all down for you in graphs etc. Most people need at least 1500 or more calories just to keep the fires of there motablism going.Especially if you are exercising which I assume you all are.
Also include good fats in your diet, eating 40 grams of fat is not bad if it includes good fat not all saturated stuff from fast food. Flax seed oil is a good suppliement has omega 6 3 and 9.
I am now eating lots of veges, fruit, meat, good carbs and good fats and loving the results.