Immunonutrition

Immunonutrition is a nutrition approach that aims to influence the immune system and inflammatory response by providing specific nutrients with immune-modulating properties. It is usually delivered as specialized enteral formulas and, less commonly, as parenteral nutrition, and is used to support immune function, wound healing, and recovery in certain clinical settings.

The concept centers on nutrients such as arginine, omega-3 polyunsaturated fatty acids (EPA and DHA), and nucleotides, often combined with glutamine. These components are thought to support lymphocyte activity, enhance gut barrier integrity, and modulate the balance between pro- and anti-inflammatory mediators. The goal is to optimize immune competence while reducing infection risk and systemic inflammatory burden in stressed or catabolic patients.

Immunonutrition has been studied primarily in patients at high risk of infection or prolonged catabolism, including those undergoing major abdominal or thoracic surgery, burn or trauma patients, and some cancer patients. Evidence from randomized trials and meta-analyses indicates potential reductions in postoperative infections and, in some cases, shorter hospital stays, but results are heterogeneous. Variability in formulations, dosing, patient selection, and outcome measures means benefits are not universally observed, and some reviews call for caution in extrapolating findings to all patient groups.

Safety considerations include potential cardiovascular effects of arginine in septic or hemodynamically unstable patients, necessitating individualized assessment. Guidelines generally endorse considering immunonutrition for selected high-risk surgical patients or other clearly defined groups, while recommending caution and ongoing evaluation in broader ICU or critical illness populations.

Delivery typically involves specialized immune-enhancing enteral nutrition, with dosing and timing tailored to the clinical condition and broader nutritional goals.