Gut microbiota ecology is altered in obesity and could link obesity and its complications.
Bariatric surgery enables a major and sustained weight loss therefore improving obesity
the investigators primary aim is to evaluate gut microbiota adaptation to weight loss and the
specific role of energetic restriction. Furthermore we aim to compare gut flora of obese
patients post bariatric surgery to that of lean healthy volunteers.
Thus, the investigators plan to compare gut microbiota from 140 obese individuals before and
after either restrictive (gastric banding) procedures or gastric bypass procedures to that of
40 lean healthy volunteers at baseline.