Behavioural interventions appear to improve weight loss at 12 months after bariatric surgery .
Background Significant , sustained weight loss through conventional , non-surgical interventions is often unattainable for people with severe obesity ( e.g. BMI ≥40 or ≥35 kg/m2 with co-morbidities ) .
Bariatric surgery is effective in treating severe obesity , but surgery alone without additional behaviour change management may not result in optimum long-term weight loss and maintenance .
This systematic review and meta- analysis of r and omised controlled trials evaluated the effectiveness of lifestyle interventions before and /or after bariatric surgery .
Benefits to patients choosing preoperative weight loss in gastric bypass surgery: new results of a randomized trial.
BACKGROUND Historically , preoperative weight loss has been encouraged for patients undergoing gastric bypass surgery  to decrease liver mass , technically facilitating the procedure . In an earlier prospect i ve r and omized trial investigating effects of preoperative weight loss on patients ' clinical outcomes , we reported no differences in postoperative complications or weight-loss profiles at 6-month followup . This article demonstrates results of the same study , with 1-year followup . STUDY DESIGN One hundred consecutive patients in an 18-month period preparing to undergo gastric bypass surgery at Stanford University Medical Center were selected . Fifty patients were r and omly assigned to lose 10 % or more of their excess body weight preoperatively , and 50 patients were assigned to no preoperative weight-loss requirements . After 1 year , patient demographics and data on postoperative complications , cure or improvement of comorbidities , and differences in weight-loss profiles were collected . RESULTS At 1 year , the 2 groups had similar preoperative demographics and body mass indexes ( BMI s ) . Patients in the weight-loss group , on average , lost 8.2 % of their excess body weight preoperatively compared with the nonweight-loss group , which gained 1.1 % ( p = 0.007 ) . After a year , the patients in both arms of the study showed no difference in weight , BMI , excess weight-loss , and number of remaining comorbidites . But when patients were divided according to those who had lost at least 5 % of their excess body weight preoperatively , the 1-year results for excess weight-loss , weight , and BMI were much lower for the weight-loss group . CONCLUSIONS Preoperative weight loss in patients undergoing gastric bypass surgery  is safe and feasible . It should be encouraged , because it will markedly improve longterm weight loss
Behavioural interventions appear to improve weight loss at 12 months after bariatric surgery .
Background Significant , sustained weight loss through conventional , non-surgical interventions is often unattainable for people with severe obesity ( e.g. BMI ≥40 or ≥35 kg/m2 with co-morbidities ) .
Bariatric surgery is effective in treating severe obesity , but surgery alone without additional behaviour change management may not result in optimum long-term weight loss and maintenance .
This systematic review and meta- analysis of r and omised controlled trials evaluated the effectiveness of lifestyle interventions before and /or after bariatric surgery .