OBJECTIVES: The United States is experiencing an obesity epidemic with 67% of adults being either overweight or obese.  While it is known that excessive weight increases the opportunity for skin infections, this relationship has not been well studied.  This study contributes to the knowledge about the relationship between these two conditions.  METHODS: Using the H-CUP national database for inpatient hospitalizations, this study analyzed the data from hospitals in the Southern states for the number of skin and soft tissue infections in 2003, 2005 and 2007 in adults.  The proportion of patients who were also coded as obese in this population was quantified.  Two t-tests were performed comparing the average length of stay for patients who were obese and not obese and the average total hospital charges for patients who were obese and not obese. Two linear regressions analyzed the impact of obesity on the cost of health care by using length of stay and total hospital charges as dependent variables. RESULTS: The proportion of patients hospitalized for skin and soft tissue infections who were also obese increased from 48.09% in 2003 to 51.7% in 2007.  The average length of stay was 7.97 days for non-obese patients verses 4.6 days for patients coded as obese which was statistically significant.  The average total hospital charges were $26,653 for non-obese patients compared to $20,876 for obese patients.  This was also statistically significant.  Surprisingly, the co-morbidity of obesity has a negative predictive value for both hospital length of stay and total hospital charges. CONCLUSIONS: It is possible that patients who are obese are being discharged sooner because of differences in severity of infections.  More research is needed to determine whether obesity is a causal factor in skin and soft tissue infections and how this is affecting the cost and delivery of health care.