Calorie restriction and the Mediterranean diets: a pilot-study on the Apulian and Sicilian Prototypical Mediterranean Diets

The present PhD thesis collects the work of my three years Doctoral degree in Human Food and Nutrition Sciences, which I started at Washington University in Saint Louis (MO, USA) in 2013, and continued at Campus Bio-Medico University of Rome (Italy), from February 2014 to December 2015. In the first chapter, I present the main subjects studied during the first year of PhD program, thoroughly exploring their features and systematic applications: Calorie restriction and a number of related topics, such as Intermittent Fasting and Calorie Restriction Mimetics. In fact, throughout the year spent at the Washington University in St Louis, I worked with professor Luigi Fontana, who has been studying Calorie Restriction (CR) for as many as twenty years, and currently leads as the Principal Investigator (PI) of a clinical research team at the Division of Geriatrics and Nutritional Sciences and Center for Human Nutrition, Washington University School of Medicine. Within this context, I took part in three different clinical studies, two of which are currently still ongoing, and I learnt for the first time how clinical research really works, quickly developing a true passion for it. Thanks to this experience, I could write and see published my first two papers: one regarded the role of CR in promoting healthy longevity, and the other presented the latest data on long-term CR in enhancing cellular quality-control processes in human skeletal muscle. I am still now very passionate about this theme, thence I have chosen to thoroughly discuss it in this chapter, to illustrate both the state of the art and the future perspectives of such a debated topic. In the second chapter, I expose an overview of the literature regarding the features of the Mediterranean Diet (MD). More specifically, I first present the original MD model, then I compare it with four other dietary patterns – basing such evaluation on the available scientific data -, and afterwards I illustrate the latest evidences on the MD's role in preventing multifactorial diseases and promoting longevity. Finally, this section also aims at introducing my own PhD project, which is fully described in the third and last chapter of my dissertation. In this chapter, I describe the pilot study I performed between March 2014 and October 2015, within two different areas of Southern Italy. This study was realized thanks to the Campus Bio-Medico University, and particularly to professor Raffaele Antonelli Incalzi, who first exposed to me the idea of investigating the evolution of the MD by characterising the past dietary pattern of a delimited Mediterranean area, in order to better understand whether the diet was more respondent to the MD original model six to seven decades ago than it is today, as well as if the current diet can be considered 'Mediterranean' in its real sense. To investigate this hypothesis, we performed the "Prototypical Mediterranean Diet study" within two selected and geographically delimited areas of Southern Italy, by comparing the diet adopted sixty to seventy years ago (Prototypical Mediterranean Diet, PMD) with the contemporary one (Contemporary Mediterranean Diet, CMD). More specifically, we first collected quali-quantitative data on both the PMDs and the CMDs by singularly interviewing the 208 recruited subjects; we then analyzed the macronutrients and micronutrients intakes for both groups and carried out the qualitative characterization of the two PMDs; lastly, we verified to which extent both the PMDs and the CMDs fitted the recommendations of two well recognized international guidelines, the Italian dietary recommendations (LARN) and the USDA dietary guidelines.