**2. Nutritional support in clinical AP**

### **2.1 Overview**

Nutritional therapy and nutritional supplements have great advantages in maintaining the integrity of intestinal barrier, providing major immunomodulatory and antioxidant effects, but more importantly restoring energy balance [21]. The main benefit of nutritional support lies in its immunologic effect, including maintenance of normal intestinal mobility and IgA production, prevention of bacterial overgrowth and infection, diminished bacterial translocation, promoting adequate intestinal permeability [22], decreasing the inflammatory response [22–24], and disease severity, and also promoting a better resolution of the disease process (i.e., duration of systemic inflammation, hospital length of stay) [23, 25]. Clinical evidence suggests that dietary antioxidants and supplements have the potential in protecting against the augmented inflammatory response of the pancreas and oxidative stress during the initial phase of AP. This includes the use of glutamine, antioxidants, probiotics, omega-3 fatty acids, as well as different formulations of enteral and parenteral nutrition [21, 26–28].

## **2.2 Metabolic response to acute pancreatitis**
