The short answer: Eat meat and vegetables, nuts and seeds, some fruit, little starch, and no sugar. Keep intake to levels that will support exercise but not body fat. To optimize health and fitness, you will need to measure and record intake, evaluate performance and potentially change intake until the desired results are achieved. This approach to diet is no different than the CrossFit approach to workouts. To start, we recommend everyone give the baseline Zone Diet prescription a try for four weeks. Doing so will help you establish measurable, observable, repeatable data on your input (food) and output (performance). Once you have completed a minimum baseline term of four weeks, you might find you have to make adjustments to the prescription until you achieve optimal levels of health and fitness. This type of measured, systematic self-observation will be the best guide as to whether you should eat any type of food or implement any diet “strategy.” For instance, experimentation will give you valuable information on grains, legumes, dairy, and salt, and it can even help you plan the frequency and timing of your meals. You might need to adjust your food intake for your lifestyle, goals, discipline, commitment level, etc. You might choose to experiment with supplementation, post-workout nutrition, fasting and so on. You might choose to include a cheat meal, eat more fat, consume more food, etc. Overall, diet is specific to each individual, and you can optimize your diet by carefully tracking input and output.