An isotope signature for diffuse idiopathic skeletal hyperostosis?

OBJECTIVES: Diffuse idiopathic skeletal hyperostosis (DISH) has recurrently been associated with a rich diet (high in protein and higher trophic level foods); however, very few studies have investigated this link using carbon and nitrogen (δ (13)C and δ (15)N) stable isotope analysis. This paper explores the relationship between DISH and diet in two Roman urban communities by analyzing individuals with and without DISH. MATERIALS AND METHODS: δ (13)C and δ (15)N analysis carried out on collagen from 33 rib samples (No DISH: 27; early DISH: 4; DISH: 2) selected from individuals buried at the Romano‐British site of Baldock (UK), 41 rib samples (No DISH: 38; early DISH: 3) from individuals from the Catalan Roman site of Santa Caterina (Barcelona, Spain). Additionally, six faunal samples from Baldock and seven from Santa Caterina were analyzed. RESULTS: Standardized human isotope data from Santa Caterina show high δ (15)N probably associated to a diet combining terrestrial resources and freshwater fish. In contrast, isotope results from Baldock suggest a terrestrial‐based diet. Individuals with DISH do not show isotopic ratios indicative of rich diet and there is no correlation between stage of DISH development and δ (13)C and δ (15)N. CONCLUSION: The results of this study suggest that individuals with DISH followed a similar or isotopically similar diet as those individuals without DISH in Baldock and in Santa Caterina and therefore, while DISH may have been influenced by individual's dietary habits, this is not reflected in their isotopic signature.