Previous studies have suggested that binge eating disorder (BED) impairs weight loss following bariatric surgery, leading some investigators to recommend that patients receive behavioral treatment for this condition before surgery. However, many of these investigations had significant methodological limitations. The present observational study used a modified intention-to-treat (ITT) population to compare 1-year changes in weight in 59 surgically treated participants, determined preoperatively to be free of a current eating disorder, with changes in 36 individuals judged to have BED. Changes in weight and binge eating in the latter group were compared with those in 49 obese individuals with BED who sought lifestyle modification for weight loss. BED was assessed using criteria proposed for the Diagnostic and Statistical Manual (DSM) 5. At 1 year, surgically treated participants without BED lost 24.2% of initial weight, compared with 22.1% for those with BED (P > 0.309). Both groups achieved clinically significant improvements in several cardiovascular disease (CVD) risk factors. Participants with BED who received lifestyle modification lost 10.3% at 1 year, significantly (P < 0.001) less than surgically treated BED participants. The mean number of binge eating days (in the prior 28 days) fell sharply in both BED groups at 1 year. These two groups did not differ significantly in BED remission rates or in improvements in CVD risk factors. The present results, obtained in carefully studied participants, indicate that the preoperative presence of BED does not attenuate weight loss or improvements in CVD risk factors at 1 year in surgically treated patients. Longer follow-up of participants is required.