The Ideal Candidate for Adjustable Band Bariatric Surgery In order to qualify for bariatric surgery, patients do need to satisfy certain minimum requirements with regards to weight and body mass index or BMI. And those are numbers and statistics that came out back in 1991 when the National Institute of Health determined that a patient with a minimum BMI of 35 and associated medical conditions would be good candidates for bariatric surgery. Today, we still use those same criteria with regards to body mass index. And wait, but they become a little bit more lenient because of the safety associated with the operation.