Food and disease at the Renaissance courts of Naples and Florence: a paleonutritional study.

A paleonutritional study of the Medici Grand Dukes in Florence (16th-17th centuries) and of the Aragonese Princes in Naples (15th-17th centuries) was performed. Carbon and nitrogen stable isotope analysis of bone collagen showed high values of delta(15)N at the level of carnivores and demonstrated a diet that was very rich in meat. delta(13)C values are in accordance with an intake of fish, especially for the Aragonese series from Southern Italy, which can be estimated at 14-30% for the Medici and 12-40% for the Aragonese. Adherence to medieval fasting is likely to have been the main reason for this dietary change.