Everything you ever wanted to know about weight loss surgery

But the truth is that weight loss surgery is a lot more complicated than that.

Formally known as bariatric surgery, weight loss surgery is a term used to describe many different types of procedures, which involve reapportioning or rerouting your stomach and intestines to reduce your appetite and facilitate digestion, resulting in significant weight loss. Within the medical community, the controversy surrounding bariatric surgery has been swirling for years. While most doctors will recommend that patients looking to lose weight should adopt major lifestyle changes before considering bariatric surgery, many experts agree that for some people, it is a viable option.

If your body mass index (BMI) is 35 or higher (the official definition of obesity is 30 or higher) and if you have two or more obesity-related chronic diseases, like diabetes or high blood pressure, you might be a good candidate for the procedure. says Stacy Brethauer, M.D., a surgeon at Cleveland Clinic and president of the American Society for Metabolic and Bariatric Surgery, and your insurance will likely cover the procedure. If your BMI is 40 or higher, you qualify even if you aren't experiencing those other health issues.

“Bariatric surgery should not be the first option considered, but it should also not be the last resort,” she adds.

Plus, if you fall into this category and have consistently failed to maintain weight loss after trying traditional methods in the the past, weight loss surgery might be for you.

“The truth is our bodies are designed to resist starvation, but they’re not designed to lose weight,” says Erik Dutson, M.D., an associate professor and bariatric surgeon at UCLA Medical Center. “Diet and exercise are critical to a healthy lifestyle, but when you look at the statistics and meta-analyses we have going back many years, you find 98 percent of patients who lose weight through diet and exercise gain it back within six months.”

That said, any time you go under the knife, it comes with risks. The main question: Is the surgery right for you—and if so, do the risks outweigh the reward? If you’ve been debating, here is what you should know about the most common types of bariatric surgery and what to expect after the operation.

1. Sleeve Gastrectomy

A sleeve gastrectomy involves removing the top 80 percent of your stomach. “The top areas of the stomach are more involved with storage, while the bottom of the stomach serves as the grinder that sends food downstream to the intestines,” Dr. Dutson explains. “So we’re removing that top portion while leaving the bottom.”

Since your stomach is much smaller following the procedure, it holds less food, causing you to feel full very quickly. The removal of the top half of the stomach also causes beneficial changes to hunger hormones and gut-brain communication.

“We’ve found that three weeks after the procedure, there is already a profound change in the way the brain responds to food and appetite,” Dr. Dutson says.

For those with inflammatory bowel disease, other bowel issues, or prior operations, this procedure is usually the go-to option, Dr. Brethauer adds.

The Pros: Patients can expect to lose 100 pounds during the first year following a sleeve gastrectomy. It also requires a shorter hospital stay than other weight loss procedures.

The Cons: Sleeve gastrectomy is non-reversible and can potentially put you at risk for long-term vitamin deficiencies, according to the American Society for Metabolic and Bariatric Surgery (ASMBS).

2. Gastric Bypass

Gastric bypass is slightly more complicated than a sleeve gastrectomy and is often considered the “gold standard” bariatric procedure, Dr. Dutson says.

The surgery involves separating the top 10 percent of your stomach from the bottom 90 percent. That small top portion is made into a “pouch,” which is then connected directly to a middle portion of your small intestine. The remaining stomach and the top part of the small intestine is also tied into the small intestine farther down.

The part of your stomach that receives food is much smaller, leaving you feeling full very quickly. In fact, the food you eat will actually bypass most of your stomach and the upper part of your small intestine, causing you to absorb fewer calories, according to National Institute of Diabetes and Digestive Kidney Diseases.

By keeping the rest of the stomach and connecting it to the small intestine, your stomach continues to produce digestive enzymes and hormones, which mix in with the food farther down your GI tract, Dr. Dutson explains.

“For patients with diabetes or reflux disease, those two issues are managed a little better with gastric bypass,” Dr. Brethauer adds.

The Pros: Gastric bypass can help you lose 60 to 80 percent of your excess weight. Patients typically continue to lose more weight in the long term than those receiving a sleeve gastrectomy, explains Dr. Brethauer.

The Cons: Because gastric bypass involves a little more rerouting and changing of your digestive anatomy, it comes with slightly higher risks. Those include ulcers or blockages, and also the unintended healing or closing-off of surgery connections, which could require emergency or follow-up procedures, says Dr. Dutson.

3. LAP-BAND Surgery

Gastric band or LAP-BAND surgery involves installing a band around the top portion of your stomach to limit the amount of food you can consume.

The Pros: It doesn't require any cutting of the stomach or rerouting of the intestines, according to the ASMBS.

The Cons: While the surgery used to be popular, it is now seldom performed, Dr. Dutson says. “You heard a lot about it a decade ago, but in the long-term, we’ve learned it’s not a good option for most patients,” he explains.

Just 20 percent of patients experienced good results, while most had problems—including inadequate weight loss, or issues associated with the band shifting or “expanding” into surrounding organs, which can cause pain or, in very rare cases, even death.

What Happens After Weight Loss Surgery?

The surgery recovery process is intense: “Because the stomach has been cut, patients are usually on a liquid diet for two weeks while they’re healing,” Dr. Dutson says. After about 6 weeks, patients can go back to eating regular whole foods.

Over time, the remaining stomach will loosen a bit and allow for less restrictive eating, but post-op patients will always have to watch what they eat to ensure they’re not sabotaging the surgery or failing to get the nutrients they need. All patients take multivitamins and, in some cases, protein supplements to ensure they’re meeting their body’s nutritional needs.

You’re also at risk for complications. Hernias, bowel disorders, digestive issues (like diarrhea or vomiting), ulcers, and malnutrition are just a few of the potential downsides. Luckily, these complications are experienced by a small percentage of patients—just 1 to 2 percent, Dr. Brethauer says.

Bottom line: Bariatric surgery isn’t a cure-all, or a way around a healthy diet and exercise. It does, however, allow traditional lifestyle improvements to work where they failed before, Dr. Dutson says.

The success of the surgery is largely up to you. “Even the most perfectly done operation will fail if patients don’t get their act together,” he says, but if you discuss it with your doctor, and he or she thinks you’re a viable candidate, it might be worth careful consideration.