What is Bariatric Surgery? Bariatric surgery provides an alternative option for weight loss for patients who meet the appropriate medical criteria, and for whom diet and exercise have proven ineffective. What are the 4 types of bariatric surgery? The most common types of bariatric surgery are sleeve gastrectomy, gastric bypass, and adjustable gastric banding. Lap banding is also known as laparoscopic adjustable gastric banding. During lap banding, your surgeon places an adjustable band around the top of your stomach.