Simply add protein-rich vegetarian foods to your current diet to maintain the correct protein to carbohydrate ratio. Ideal choices are firm and extra firm tofu and isolated soybean protein powder. The new generation of soybean-based meat substitutes (hot dogs, hamburgers, sausages, etc.) are another excellent way of turning a carbohydrate-rich vegetarian diet into a vegetarian Zone Diet. Traditional vegetarian protein sources, such as beans, have an exceptionally high amount of carbohydrate for the amount of protein they provide, which makes it impossible to achieve the desired protein-to-carbohydrate balance to enter the Zone. Also, check out "The Soy Zone" by Dr. Barry Sears.