Assessing Semi-Liquid Diets and Taste Alterations in Bariatric Surgery Patients: A Pilot Comparative Study of Foods for Special Medical Purpose and Traditional Weaning

Objective: Obesity is a global epidemic, associated with metabolic disorders and significant health risks. It is often treated with bariatric and metabolic surgery (BMS), such as Roux-en-Y gastric bypass and sleeve gastrectomy. These interventions impact not only weight loss but also taste perception and food preferences, possibly influencing dietary habits. This study investigates taste and nutritional outcomes during the post-BMS weaning phase, evaluating an alternative semiliquid diet with “Foods for Special Medical Purposes” (FSMPs) for improved taste acceptance and nutrient intake. Methods: Thirty-two patients undergoing BMS were divided into two groups 16 were placed on an FSMP-based diet (Group A) and 16 on traditional homogenized foods (Group B). Sensory evaluation included taste strips, sensory questionnaires, and weekly dietary questionnaires. Hematochemical analyses and bioimpedance measurements were conducted presurgery (T0) and 1-month postsurgery (T1) to assess nutrient status and body composition. Results: Patients in Group A showed improved protein intake and a trend toward better compliance with the FSMP diet. Significant changes in taste perception were noted, particularly for sour and salty tastes, with patients reporting altered taste intensity and preferences, especially for high-calorie foods. There were no significant differences in anthropometric or hematochemical outcomes between the groups, although FSMPs showed a marginal benefit in maintaining protein levels. Conclusions: FSMPs may offer an effective alternative in the post-BMS weaning phase, supporting nutrient intake and adherence to dietary guidelines. The observed changes in taste perception highlight the importance of tailored dietary strategies to support long-term dietary adjustment and weight management.