context: If you're getting ready to have weight loss surgery, you're probably looking ahead to the results. You can expect to lose a lot of weight. If you have a weight-related medical condition, like type 2 diabetes or sleep apnea, those conditions may improve. And almost all people who get weight loss surgery -- 95% -- say their quality of life improves, too. You'll want to get ready for the recovery and know what you'll need to do to make the changes last. Ask your doctor exactly what you can expect. It may depend, in part, on what you weigh now and the type of surgery you get. Sleeve gastrectomy is becoming a more popular weight loss surgery. People who get sleeve gastrectomy lose about 40% of their extra weight. On average, people lose 60% of their extra weight after gastric bypass surgery. Gastric banding is no longer a commonly performed weight loss surgery. Most gastric bypass surgery is laparoscopic, which means the surgeon makes small cuts. That makes for shorter recovery time. Most people stay in the hospital for 2 to 3 days, and get back to normal activities in 3 to 5 weeks. If the surgery must be "open," meaning the surgeon has to make a larger cut, healing takes longer. There are potential short-term and long-term complications from having weight loss surgery. Long-term risks vary depending on the type of surgery. Approximately 40% of people experience some sort of complication. Less than 5% have serious complications. If you do have any problems that concern you, check in with your doctor. Some common side effects include: Constipation is common after weight loss surgery. Your doctor can let you know how to handle it. Avoid granular fiber ( Metamucil or psyllium), which can cause obstructions. Dumping syndrome happens after eating high-sugar meals after weight loss surgery. Sodas or fruit juices are often to blame. The sugary food rushes through the stomach and can cause nausea, vomiting, and weakness. Gallstones are common when you lose a lot of weight quickly. Up to 50% of patients will develop gallstones after gastric bypass surgery, and these are usually harmless. Sometimes, gallstones can cause nausea, vomiting, and abdominal pain. About 15% to 25% of people need surgery to remove their gallbladder after gastric bypass surgery. Wound infections can happen up to 3 weeks after surgery. Symptoms include redness and warmth, pain, or thick drainage (pus) from the surgical wound. Wound infections require antibiotics and sometimes further surgery. Serious side effects include: Bleeding in stool, which can appear as reddish or black stools, can be serious. Let your doctor know about this immediately, or go to an emergency room. Blood clots to the lungsare rare, happening less than 1% of the time. They can be life-threatening. But blood clots can usually be prevented with blood thinning drugs and frequent activity. Leaks in the new connections made by the weight loss surgery are rare, but serious. They usually occur within 5 days of the surgery. Abdominal pain and feeling ill are common symptoms -- these should prompt a call to your doctor. Also, you may notice that your skin is sagging. You may choose to get surgery to remove it. Weight loss surgery changes how your body handles food. It becomes harder to absorb certain nutrients, including: Iron Vitamin B12 Folate Calcium Vitamin D You don't have to fall short on those nutrients. Ask your doctor if you need to take supplements. You can get dramatic results from weight loss surgery. You'll need to back those up with lifestyle changes to keep the pounds off. These tips can help: Eat small, frequent meals. The small stomach created by weight loss surgery can only hold so much. Eating large meals can cause problems. Many people with obesity are binge eaters. Adapting to eating smaller meals can be a challenge. Commit to good nutrition . Ask a dietitian to help you create a plan that will get you all the nutrients you need. Exercise. It helps you keep the weight off, and it's often easier after weight loss surgery, because losing weight may have helped your joints. Many weight loss surgery centers offer programs to help people shift to a healthier lifestyle before and after weight loss surgery.