Background and Objectives: The Mediterranean diet has been demonstrated to provide a range of health bene- fits in observational and clinical trials and adopted by various dietary guidelines. However, a broad range of defi- nitions exist impeding synthesis across trials. This review aims to provide a historical description of Mediterrane- an diets, from the ancient to the modern, to inform future educational and diet index tool development represent- ing the ‘traditional’ Mediterranean diet. Methods and Study Design: Nine databases were searched from incep- tion to July 2015 to identify papers defining the Mediterranean diet. The definition accepted by the United Na- tions Educational, Scientific and Cultural Organization (UNESCO) was also reviewed. Results: The ‘traditional’ Mediterranean diet is described as high in unprocessed plant foods (grains, vegetables, fruits, legumes, nuts/seeds and extra virgin olive oil), moderate in fish/shellfish and wine and low in meat, dairy, eggs, animal fats and dis- cretionary foods. Additional elements relating to cuisine and eating habits identified in this review include fre- quent intake of home cooked meals; use of moist, lower temperature, cooking methods; eating main meals in company; reduced snacking occasions; fasting practice; ownership of a vegetable garden; use of traditional foods and combinations; and napping after the midday meal. Conclusions: Scope exists for future tools to incorporate additional elements of the ‘traditional’ Mediterranean diet to improve the quality, consistency, and synthesis of ongoing research on the Mediterranean diet.