The Paleo Diet is a lifelong way of eating that will gradually restore your normal body weight, health, and well-being. If you follow the dietary guidelines and principles I have laid out, you will reap all the benefits that humanity’s original diet has to offer. Your health will immediately improve, and you will definitely begin to lose weight.
You’ll find three two-week meal plans. Any of them will work for you; the only difference is in the number of Open Meals. Level I allows you three Open Meals per week, Level II allows two per week, and Level III allows one. Just use the appropriate number of Open Meals for your level of the diet, and you’re set. Use these guidelines and the recipes in chapter 10 to help you embrace the diet that nature designed for us all.
If you are a beginner, you may want to adhere to Level I for two to four weeks before you move to Levels II and III—or, if you’re happy there, you may want to stay at this level of the diet. Note: You should try to include no more than one Open Meal on any given day, and do not try to make up for lost time with your meal choices. Use them as a safety net as you get used to humanity’s real foods: fresh, lean meats, seafood, and fruits and vegetables.
Should you definitely plan to move up to Levels II and III? Not necessarily. Depending on your nutritional and weight-loss goals, you may be happy with the results you achieve at Level I, particularly if you limit your consumption of the non-Paleo foods while consuming your Open Meals.
If you decide to jump into the Paleo Diet more rapidly by advancing to Level II, then you may substitute two Open Meals a week for any of the meals in the meal plans.
If you are one of those people who can make long-term behavioral changes abruptly and want to go cold turkey to the Stone Age, or if it is absolutely essential that you maximize the weight-loss and health benefits of this program, then you should adopt Level III. On Level III you should substitute one Open Meal a week for any of the meal plans.
However, most people do quite well at Level II, and this is the level I recommend for maintenance, except for dieters with chronic diseases, who may do better with long-term adherence to Level III.
Paleo Diet Level Guidelines Source :
The Paleo Diet Revised Edition, Loren Cordain, Ph.D.