Objectives: Many Roman pontiffs are known to have had kidney stone disease. However, no specific report has explored the prevalence of the various stones in popes, which is the purpose of this study.
Materials and methods: We extensively studied the histories of all popes (n = 264) from Saint Peter to John Paul II (34-2005).
Results: Among 206 popes reigning from 537 to 2005, 26 popes (12.6%) had uric acid stones. In the same period, 11 of 206 popes (5.3%) had nongouty stones (mainly calcium stones). In total, 37 of 208 (17.8%) popes complained of kidney stone disease. The ratio of calcium stone formers to other stone formers (including uric acid) was 0.42.
Conclusions: The data suggest a higher prevalence of uric acid stones, which is linked to higher consumption of meat and sodium chloride. However, the last pope with kidney stone disease died in 1914. Although renal stone disease disappeared from papal palaces, population studies now indicate an increase in uric acid levels in the general population. The data can be explained based on the "Theory of Epidemiological Transition," pointing to the importance of education in eradicating poor lifestyles.