Objectives This randomized controlled trial aimed to assess whether structured dietary interventions, implemented both before and after orthognathic surgery, could minimize postoperative weight loss and thereby enhance recovery during the first eight weeks.

Material and Methods The study was conducted at Aalborg University Hospital, Denmark, from April 2017 to April 2022, involving patients undergoing single- or bimaxillary surgery. Participants were randomly allocated into two intervention groups receiving nutritional supplements and one control group. Body composition was assessed using a Body Composition Analyzer at five time points: pre-surgery examination, admission, and follow-ups weeks 1, 3, and 8. Primary outcome was weight, secondary outcomes included BMI, fat mass, fat-free mass, total body water, and visceral fat rating. Additional data were collected on age, gender, type of surgery, and hospitalization duration.

Inclusion Criteria:

• Adult patients of both sexes with dentofacial deformities who underwent single- or bimaxillary surgery (Le Fort I osteotomy and/or bilateral sagittal split osteotomy) were included in the study.

Exclusion Criteria: Patients not willing to complete the planned treatment in the intervention groups.