Patients receiving extracorporeal membrane oxygenation (ECMO) inherit substantial disease-associated metabolic, endocrinologic, and immunologic modifications. Along with the technical components of ECMO, the aforementioned alterations may affect patients’ needs and feasibility of adequate macro- and micronutrient supply and intake. Thus, ECMO patients are at increased risk for iatrogenic malnutrition and will require targeted individual medical nutrition therapy (MNT). However, specific recommendations for MNT in ECMO patients are limited and, with some exceptions, based on an evidence base encompassing general critically ill patients. Consequently, clinician decision-making for MNT in ECMO patients is unguided, which may further increase nutritional risk, culminating in iatrogenic malnutrition and ultimately affecting patient outcomes. The purpose of this article is to provide educational background and highlight specific points for MNT in adult ECMO patients, which might serve as an evidence-based guidance to develop institutional standard operating procedures (SOP) and nutrition protocols for daily clinical practice.