OBJECTIVES: To utilize the Cystic Fibrosis Foundation Patient Registry to evaluate whether pancreatic enzyme dose is associated with better nutritional status as measured by average body mass index (BMI) percentile. STUDY DESIGN: A retrospective analysis of the Cystic Fibrosis Foundation Patient Registry from 2005-2008 was performed. The final analysis included 42 561 patient visits from 14 482 patients 2-20 years of age taking pancreatic enzyme replacement therapy from 179 programs. Cystic fibrosis care programs were assigned to quartiles based on adjusted mean patient BMI percentiles. Differences in median lipase dose between programs in the highest and lowest BMI quartiles were examined using a mixed effects model that adjusted for individual patient BMI, age, race, ethnicity, forced expiratory volume in 1 second percent, acid-blocker use, presence of Pseudomonas aeruginosa, nutritional supplement use, growth hormone use, and diagnosis of cystic fibrosis-related diabetes. RESULTS: A significant difference in median enzyme dose existed between the highest and lowest BMI quartiles. Multivariable analysis demonstrated the effect persisted after adjustment for covariates. Highest quartile programs had a median enzyme dose of 1755 lipase units/kg/meal compared with 1628 lipase units/kg/meal for lowest quartile programs. CONCLUSION: Patients attending US cystic fibrosis programs achieving highest nutritional outcomes, measured by mean BMI percentile, have higher enzyme dosing than those attending programs at lower performance levels. Further randomized clinical trials are necessary to determine the role of enzyme dose in improving nutritional outcomes.