Pancreatitis is an illness that can bring about nutritional changes in connection with the underlying cause, the metabolic reaction to stress or the limitations that this pathology may represent for the processes of digesting and absorbing nutrients or for tolerating the diet. Although nutritional support is well accepted as a therapeutic measure in patients with severe acute pancreatitis, there is some dispute over the route of administration. In patients with mild pancreatitis, the use of parenteral nutrition may be accompanied by an increase in complications, particularly due to catheter-related sepsis, but in severe cases, early parenteral nutrition has been associated with a lower incidence of complications and a drop in mortality. Although parenteral nutrition is the preferred conventional method for the nutritional support of patients with pancreatitis, enteral nutrition offers the advantages of being more physiological, safer and less costly, at the same time as it seems to have a favourable influence on the progress of the pancreatitis. For this reason, the current recommendations suggest the use of enteral nutrition via the jejunum in those cases where the severity of the pancreatitis indicates nutritional support. Further research is, however, necessary in this field to clarify the group of patients in which the benefits of nutritional support would be most evident, the most appropriate type of diet, and the role of enteral nutrition on the evolution, both locally and systemically, of the changes brought about by the inflammation of the pancreas.