BackgroundFew studies evaluated the association between nutritional disorders, quality of life and weight loss in patients undergoing bariatric surgery.AimTo identify nutritional changes in patients undergoing bariatric surgery and correlate them with weight loss, control of comorbidities and quality of life. MethodA prospective cohort, analytical and descriptive study involving 59 patients undergoing bariatric surgery was done. Data were collected preoperatively at three and six months postoperatively, evaluating nutritional aspects and outcomes using BAROS questionnaire. The data had a confidence interval of 95%.ResultsThe majority of patients was composed of women, 47 (79.7%), with 55.9% of the series with BMI between 40 to 49.9 kg/m². In the sixth month after surgery scores of quality of life were significantly higher than preoperatively (p<0.05) and 27 (67.5 %) patients had comorbidities resolved, 48 (81.3 %) presented BAROS scores of very good or excellent. After three and six months of surgery 16 and 23 presented some nutritional disorder, respectively. There was no relationship between the loss of excess weight and quality of life among patients with or without nutritional disorders.ConclusionsNutritional disorders are uncommon in the early postoperative period and, when present, have little or no influence on quality of life and loss of excess weight.