Over the last 20 years there has been considerable research into the use of immunonutrition, also referred to as pharmaconutrition, in the management of patients undergoing and recovering from elective gastrointestinal surgery for malignancy. In this group of patients, the use of pharmaconutrition seems to confer superior outcomes to standard nutrition formulations with regards to postoperative infective complications and length of hospital stay. It is therefore frequently recommended for use in elective gastrointestinal oncological surgical populations. However, it remains unclear whether the data supporting these recommendation is robust. Studies reporting improved outcomes with pharmaconutrition frequently compare this intervention with non-equivalent control groups, do not report on the actual nutritional provision received by study participants, overlook the potential impact of industry funding on the conduct of research and do not adopt a multi-disciplinary approach to the research undertaken. For these reasons, an urgent critical re-appraisal of the use and recommendations of pharmaconutrition in this group of patients is warranted to resolve some of the above mentioned issues.