Nutrition is a huge part of how successful you will be in CrossFit and in your life, whether your goal is to lose weight or just become stronger and faster.  You are definitely what you eat and your food has everything to do with how you look, how you feel, and how you perform at the gym and as well as in life.

The following paragraphs are courtesy of CrossFit Inc.:

Food quality and quantity
These two main categories must be addressed when dealing with nutrition.  Food quality refers to what kind of food you are putting in your body.  We address this with the Paleolithic (Paleo) diet.

Food quantity refers to how much of that food are you putting in your body.  This is where the Zone diet comes in.

What Should I Eat?
In plain language, base your diet on garden vegetables, especially greens, lean meats, nuts and seeds, no grains, 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.

The Caveman or Paleolithic Model for Nutrition
Modern diets are ill suited for our genetic composition. Evolution has not kept pace with advances in agriculture and food processing resulting in a plague of health problems for modern man. Coronary heart disease, diabetes, cancer, osteoporosis, obesity and psychological dysfunction have all been scientifically linked to a diet too high in refined or processed carbohydrates.

What Foods Should I Avoid?
Excessive consumption of high-glycemic carbohydrates is the primary culprit in nutritionally caused health problems. High glycemic carbohydrates are those that raise blood sugar too rapidly. They include rice, bread, candy, potato, sweets, sodas, and most processed carbohydrates. Processing can include bleaching, baking, grinding, and refining. Processing of carbohydrates greatly increases their glycemic index, a measure of their propensity to elevate blood sugar.

A list of things and why:

Do not eat grains. This includes bread, rice, pasta, corn, oatmeal, and all of those gluten-free pseudo-grains. That’s not real food, right?

Do not eat legumes. This includes beans of all kinds, lentils, and peanuts. (No peanut butter, kids.)

Do not eat dairy. This includes butter, cheese (hard and soft), yogurt, and milk.

Do not eat sugars of any kind, real or artificial. If you must sweeten, use minimal quantities of honey, maple syrup, or agave nectar. No Splenda, Truvia, Stevia, etc

Do not eat processed foods. This includes processed bars (like Zone bars), dairy-free creamers, etc.

Do not drink alcohol, in any form.

What is the Problem with High-Glycemic Carbohydrates?

The problem with high-glycemic carbohydrates is that they give an inordinate insulin response. Insulin is an essential hormone for life, yet acute, chronic elevation of insulin leads to hyperinsulinism, which has been positively linked to obesity, elevated cholesterol levels, blood pressure, mood dysfunction and a Pandora’s box of disease and disability. Research “hyperinsulinism” on the Internet. The CrossFit prescription is a low-glycemic diet and consequently severely blunts the insulin response.

How much should I eat?
This question is answered primarily by ‘the Zone’ diet,  a diet created by Barry Sears for those looking to improve health and reduce body fat. To us, the Zone seems like a sensible and conservative plan of eating that anyone could follow:

40% of your calories from Carbohydrates, 30% from Fat and from Protein. At every meal. This balance is maintained every time food is ingested, with the intent of regulating changes in digestive hormones, namely insulin. Food is often divided into ‘blocks’, the ratios amongst which are fixed to keep designing meals somewhat simpler. Ie., a three block meal may have 3 blocks of Carbohydrates, 3 blocks of protein and 3 blocks of fat.

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