Nutritional factors have long been implicated in the causation of pancreatitis; they also have major therapeutic relevance in established disease.
Dietary intakes of macro- and micro-nutrients in aetiogenesis of chronic pancreatitis have been studied over the years. Much of this has been informed by the pivotal role of the enhanced oxidative stress model in the necrosis-fibrosis sequence that produces the hallmarks of this disease.
Micro-nutrients, such as certain trace element and vitamins, ostensibly help to quench the reactive oxygen species (ROS) released by pancreatic injury, which would activate fibrosis mediated by stellate cells. Evidence for this has come from observational and experimental studies in humans and animals. However, due to the long course of disease evolution and perhaps the non-compliant nature of the disease population itself, causal inference derived from high-level prospective cohort studies and randomised controlled trials has been difficult to obtain. Further innovative clinical research strategies may be necessary to strengthen the existing body of evidence.
Nutrition for therapeutic purposes in pancreatitis is focused on counteracting catabolism in severe acute pancreatitis (SAP), and on ameliorating deficient exocrine function in chronic pancreatitis and in the recovering phases of SAP.
In acute pancreatitis, initial severity stratification is desirable in order to predict ongoing nutritional needs. For SAP, nutritional support is necessary in the acute phase. Most guidelines recommend enteral feeding in the presence of an intact gastrointestinal tract, reserving parenteral nutrition for exceptional cases. In the recovery phase, there may be a benefit from enzyme supplements during the period of exocrine function recovery, so as to maximise bio-availability of nutrient intake.
Enzyme replacement is similarly indicated in chronic pancreatitis, and should be guided by clinical features and tests of exocrine function. In some cases, vitamin and mineral supplements may be considered. Enteral feeding is occasionally indicated where there is gastric outlet obstruction, or in malnourished patients prior to surgery.