A rodent model of caloric restriction using bone mass, microarchitecture, and stable isotope ratios: implications for revealing chronic food insufficiency in archaeological populations

ABSTRACT One important question with respect to past health and disease is the identification of patterns of caloric inadequacies. Given the substantial literature (animal and human) linking caloric inadequacy to reduced bone mass, microarchitectural deterioration, and changes in stable isotope values, we utilized a rodent model to examine whether integrating these data might help discern episodes of caloric insufficiency. Bone stable isotope values and bone morphometric data were analyzed from a sample of adult male rats in a controlled feeding study. Three-dimensional micro-computed tomography revealed substantial impacts to femoral bone mass and microarchitecture among calorie-restricted animals compared to controls, and we found significant correlations between those parameters and δ13Capatite values. Results support consideration of caloric inadequacy in differential diagnoses of bone loss within archaeological populations, and suggest that similar relationships among stable isotope signatures and bone morphometric parameters delineated within past human populations may help illuminate periods of food insufficiency.