For patients with cystic fibrosis (CF), overweight and obesity were associated with higher FEV1 compared with patients of normal weight, according to a study published in JAMA Network Open. Rita Nagy, MD, and colleagues conducted a systematic review and meta-analysis to examine the association between altered BMI or body composition and clinical outcomes in patients with CF. A total of 61 records were included in the qualitative analysis, 17 of which were included in the quantitative synthesis; the investigation included 9,114 patients. Compared with normal weight, overweight and obesity were associated with higher FEV1 (weighted mean differences, −8.36% and −12.06%, respectively). Patients with normal weight had increased odds for CF-related diabetes and exocrine pancreatic insufficiency compared with those who were overweight (OR, 1.49 and 4.40, respectively). In the analysis of pulmonary function, high heterogeneity was seen.