Adherence to Mediterranean Diet or Physical Activity After Bariatric Surgery and Its Effects on Weight Loss, Quality of Life, and Food Tolerance.

OBJECTIVE To assess whether a healthy dietary pattern or physical activity after bariatric surgery mediates the effects of surgery on weight loss, the quality of life, or food tolerance. METHODS A prospective observational study conducted in the context of a randomized controlled trial. We assessed the extent to which increasing or decreasing adherence to the Mediterranean diet (MedDiet)-assessed by MEDAS (Mediterranean Diet Adherence Screener)-and of increasing or decreasing physical activity (PA)-assessed with the Short Questionnaire of International PA (IPAQ-Short Q)-after bariatric surgery affected changes in weight, body mass index (BMI), quality of life (Moorehead-Arlet Questionnaire), and food tolerance (Suter test). Assessments were recorded at baseline and quarterly up to 12 months of surgery. RESULTS Seventy-eight morbidly obese participants undergoing bariatric surgery were assessed up to 1 year after surgery. Those individuals who increased adherence to MedDiet showed a significantly higher mean of total weight loss percentage than those who decreased or maintained their adherence during follow-up: 37.6% (35.5-39.8) versus 34.1% (31.8-36.5) (p = 0.036). No significant differences were observed in changes in weight or BMI comparing individuals who increased their PA versus those who maintained or decreased PA, nor in quality of life or food tolerance between those individuals who increased versus those who decreased adherence to MedDiet or PA during the follow-up. CONCLUSIONS After bariatric surgery, morbidly obese subjects present greater weight loss if they adhere to the MedDiet. PA after surgery is not associated with the magnitude of weight loss nor the quality of life and tolerance to diet.