In the 1960s, the recorded dietary pattern of Southern European populations was typical of the traditional Mediterranean diet. However, diets have been rapidly changing. The aim of the current work was to examine the extent by which present food habits of inhabitants residing in various Mediterranean islands uphold past dietary traditions of the Mediterranean diet. A population-based, multi-stage sampling method was used to voluntarily enroll 876 men and 936 women (aged > 65 years) from 12 Mediterranean islands. Demographic, behavioral, clinical, and dietary data were collected. Principal component analysis derived fruits, vegetables, and greens as part of the main dietary pattern across most Mediterranean regions. Surprisingly, Crete had the highest frequency of fast-food and sweets consumption. Malta had the lowest frequency of fish and vegetable consumption and the lowest MedDietScore. As Mediterranean populations gradually move away from traditional dietary patterns, public-health efforts to preserve these diets are needed.