Plant-based foods such as fruit and vegetables, nuts, natural vegetable oils and whole grains are an important component of traditional diets in Mediterranean regions. A large and consistent body of scientific evidence has provided solid evidences about the role of plant food-based diet as a whole, in the prevention of degenerative diseases. This book provides an overview of the evidence describing the health-promoting benefits of the consumption of plant food-based diets, as well as an illustration of the possible mechanisms through which the protection is carried out.