The NutriSystem diet is less of diet and more of "meal delivery plan". Dieters who don't want to think about portion sizes, planning, shopping for or cooking meals will love the NutriSystem diet plan. You simply make your food selections and then get a month's worth of meals delivered to your door in microwave-ready pouches. With NutriSystem diet, you receive three meals a day, plus a snack or dessert that are already cooked and shipped to you in what is called their "stay fresh" packaging. All you have to do is heat and eat.