Twenty-four orthognathic surgery patients were studied to determine the impact of a high-calorie liquid supplement on preventing or minimizing catabolism commonly associated with surgery. The experimental group of 12 subjects, chosen at random, consumed blenderized foods ad libitum and a high-calorie dietary supplement providing a minimum of 50% of energy requirements. The remaining 12 subjects consumed only blenderized foods and served as the control group. The nutritional status of all patients was assessed one day before surgery and on Day 7 of the first, third, and sixth postoperative week. In general, nutrient intake in the experimental group remained similar to that before surgery, whereas intake in the control group decreased significantly, particularly at the one-week postoperative evaluation. It was concluded that the addition of a high-calorie liquid supplement to the dietary regimen of orthognathic surgery patients helped maintain nutrient intake at a level comparable to that before surgery. This resulted in better maintenance of body weight and somatic protein compartments compared with the control group.