OBJECTIVES: Patients who do not incorporate diet modifications in their therapy regimen may create an undesirable escalation in blood glucose level leading to hyperglycemia and chronic complications. The objective of this study is to investigate the prevalence of diabetic patients who incorporate diet modification in their therapy, and its association with health care utilization and expenditures for the U.S. civilian noninstitutionalized population.   METHODS: Our study was conducted with a quasi-experimental design approach.  Subjects included were patients who reported being diagnosed with diabetes and reported the treatment of diabetes with diet modification from the 2011 Medical Expenditure Panel Survey. A series of weighted inferential statistics were used to test the effect of diet modification on the variables associated with health care use and expenditures. All analyses were accomplished by taking into consideration MEPS sample adjustments using SAS 9.3. RESULTS: There were an estimated 21.8 million who have been diagnosed with diabetes in the US in 2011, of which, 4.6 million (21%) did not include diet modification in their therapy.  For total health care expenditures, those who did not include diet modification had more expenditure (M = $11,230, SE = 811.84) comparing with those who included diet modifications (M = $10,638, SE = 487.25), t (172) = 25.26, p<.0001. Moreover, total inpatient expenditure for those who did not include diet modification (M = $3,003, SE = 497.3) and patients who included diet modification (M = $2545.66, SE = 251.45), revealed a significant difference between the groups; t (172) = 12.33, p<.0001. CONCLUSIONS: The study findings indicated that diabetic patients with diet modification had significant lower utilization and expenditures. Regulating diet is extremely important for people who have diabetes. It can be very effective in preventing or postponing the progression of diabetes, and subsequently managing the cost and utilization associated with it.