To demonstrate the research potential of the National Burn Repository, we examined outcomes affecting the obese burn population, specifically length of stay and mortality. This retrospective analysis evaluates burn patients from the repository coded as "obese." We queried admissions from burn units between the years 2000 to 2006 (n = 101,450). We initially intended to associate and stratify obesity with several complications and outcomes using multivariate analysis. However, because of the lack of standardized data fields, a surrogate yard stick (length of stay > or =7 days) was a straightforward and sensible outcome measurement. Mortality was used as a second outcome measurement. Two statistical approaches were used: logistic regression and the Cochran-Mantel-Haenszel test. Obese patients were 4.1 times more likely to have a length of stay > or =7 days (P < .0001) and were 2.6 times more likely to die (P < .0001) than patients not described as obese. The results not only highlighted obesity as a major challenge in burn care, but also identified means of improving the National Burn Repository to facilitate future nutrition research. The repository has vast potential to be a useful research tool for the dietitian. With standardization of the data dictionary and the addition of nutrition-related fields, such as height and weight, future research will be greatly enhanced.