**2. Management of oxidative stress in cystic fibrosis**

Nutrition plays an essential role in the survival and quality of life of CF patients. CF patients have high caloric requirements due to an increased resting energy expenditure (REE), bacterial infection, and malabsorption. REE is higher in CF patients with a more severe phenotype. Lung function and nutritional status are closely correlated, and the severe weight loss can lead to a decrease in lean body mass, with consequences for respiratory muscles. There is a significant correlation between growth retardation and the severity of pulmonary involvement [4]. Recently, Yen et al. found that greater weight at age four years is associated with greater height, better pulmonary function, fewer complications of CF, and better survival through the age of 18 years. Furthermore, greater weight for age in the peripubertal period is associated, on average, with improved tempo and timing of pubertal height growth [5]. Long-term nutritional management is as integral a part of modern care as pulmonary therapy, and is intimately linked to pulmonary outcomes.

Dietetic management is based on the replacement of pancreatic enzymes and fat-soluble vitamins (A, D, E, K), together with a high-protein diet and high calorie intake (120–125% of the normal recommended daily allowance). The recommended Body Mass Index (BMI) for adult CF patients is ≥22 kg/m2 for females and ≥23 kg/m2 for males. Overnight enteral nutrition via nasogastric tube or gastrostomy provides supplementary nutritional support when BMI is suboptimal [6].
