The aim of this study was to investigate the impact of bariatric surgery on body composition, serum zinc and serum copper levels in obese patients over a period of 12 months following laparoscopic sleeve gastrectomy. This could be important considering that this procedure has been proven to be an effective tool in achieving absolute weight loss and reducing fat tissue in morbidly obese population. Thus, our present results are confirming some important modifications behind the biochemistry of the bariatric surgery and the aforementioned impact of laparoscopic sleeve gastrectomy on serum zinc or copper and body composition.