The Effect of Mediterranean Diet Adherence and Physical Activity Level on Weight Loss After Laparoscopic Sleeve...

Metabolic and bariatric surgery (MBS) is an effective treatment for severe obesity; long-term weight loss success depends on the extent to which patients adapt to lifestyle changes. Mediterranean diet and physical activity are important lifestyle components for sustainable weight control. This study examines the effect of adherence to the Mediterranean diet and physical activity levels on weight loss in patients in the second year follow-up after sleeve gastrectomy (SG).

This cross-sectional and observational study included 97 patients who underwent SG surgery at a university hospital in Türkiye and reached the 24th-month follow-up. Data were collected using the Mediterranean Diet Adherence Screener (MEDAS) and the International Physical Activity Questionnaire-Short Form (IPAQ-SF). Weight loss efficiency was evaluated using percentage of excess weight loss (EWL%), total weight loss (TWL%), and body mass index (BMI).

Overall, 60.8% of the participants demonstrated moderate-to-high adherence to the Mediterranean diet, while 18.6% achieved sufficient physical activity levels. The EWL% and TWL% values of those with moderate-to-high adherence to the Mediterranean diet were statistically significantly higher at 3, 6, and 24 months (p < 0.01). The effect of physical activity level on TWL% was significant at 18th and 24th months (p < 0.05). The rate of weight regain in the 18-24-month period was 26.8%, with low baseline body mass index (BMI) and male gender increasing the risk, moderate-to-high adherence to the Mediterranean diet reducing it, and physical activity showing no significant effect.

Adherence to the Mediterranean diet and regular physical activity are important factors for maintaining weight loss after SG. Implementing a multidisciplinary, patient-centered case management approach may enhance long-term outcomes. Clinicians should note that reliance on self-reported diet and activity data may introduce recall and social desirability biases, highlighting the need for objective assessments in future studies.