Prior analyses of NHANES data did not explore associationsbetween markers of the metabolic syndrome(eg, overweight/obesity, diabetes) and the prevalence ofstone disease. Since the last NHANES analysis, however,prospective data from three large cohorts clearly demonstratean increasing risk of incident stone disease withobesity, weight gain, and other measures related to themetabolic syndrome [4,5]. Physiologically, obesity has beenlinked to increased renal excretion of calcium and uric acid,as well as increased urine acidity, all of which increase therisk of stone formation [8–13]. For these reasons, weinvestigated potential associations between obesity and ahistory of kidney stones. In multivariable models, weobserved statistically significant relationships between ahistory of kidney stones and gout, diabetes, and obesity.