The CrossFit dietary prescription is as follows:
From CrossFit Inc: In plain language, base your diet on garden vegetables, especially greens, lean meats, nuts and seeds, little starch, and no sugar. That's about as simple as we can get. Many have observed that keeping your grocery cart to the perimeter of the grocery store while avoiding the aisles is a great way to protect your health. Food is perishable. The stuff with long shelf life is all suspect. If you follow these simple guidelines you will benefit from nearly all that can be achieved through nutrition.
If you're a long way off from eating in the zone, start out with ADDING the good foods and it will help immensely with ELIMINATING the bad foods later. Many people get started the opposite way and fail on a diet right away.