Most studies on RFS conducted on patients with eating disorders, but few are Randomized Controlled Trials (RCT). In later years there has been a paradigm shift in regards to refeeding patients with anorexia nervosa (AN). For years, a low calorie approach has been recommended, but these recommendations has led to poor weight gain and prolonged hospital stay. Garber et al. did a systematic review on refeeding patients with AN, and concluded that higher calorie approaches on AN patients in hospital is feasible, when close medical monitoring is provided. Studies on patients with eating disorders indicate that the severity of malnutrition rather than the total energy intake predict the development of RFS. For instance a calorie level at both 125 and 1900 kcal a day led to hypophosphatemia. The great difference in recommendation for initial refeeding rates in patients with eating disorders, illustrates the lack of studies and international consensus on the topic.