Misconceptions About Bariatric Surgery

Written by: Emily Russo, MS, RD, CDN

Bariatric surgery is considered a safe and successful weight loss solution, and is statistically as safe as gallbladder removal. So why isn’t it the right choice for everyone and what are some of the potential side effects that should give us pause?

Bariatric surgery is considered a safe and successful weight loss solution, and is statistically as safe as gallbladder removal. So why isn’t it the right choice for everyone and what are some of the potential side effects that should give us pause?

For Part 1 of this article, check out Medical Intervention for Weight Loss

Since more and more people will be pursuing bariatric surgery (adults and kids alike) it seemed to me like good timing to address misconceptions about it, as there are many. As a dietitian who used to cover the inpatient bariatric surgery units, here are some recurring assumptions we encountered.

#1 – Bariatric surgery is stomach stapling
There are a few different kinds of bariatric surgery, and all of them do have a restrictive component. But it’s more involved than simply stapling the stomach.

In a Sleeve Gastrectomy, the majority of the stomach (80%) is removed so it looks more like a banana, or a sleeve. This will restrict how much food can be eaten because the stomach vessel is that much smaller. Additionally, the area where “hunger hormones” are produced is removed, which makes us feel fuller faster.

With Gastric Bypass (or roux-en-y, or shaped like a “y”), the stomach is mostly removed except for a small pouch. The rest of the unused stomach stays put, but it gets bypassed and the food goes into the tiny pouch (egg-sized).

The small intestine is divided so that one part connects with the tiny pouch and the other connects with the larger unused pouch (hence the Y-shape reference). Gastric juices and enzymes from the original stomach can still flow into the intestines, but a portion of it that is normally used to absorb nutrients is skipped. This procedure has the best outcomes for Type 2 diabetes remission.

Sleeve Gastrectomy and Gastric Bypass combined account for more than 85% of all bariatric surgeries worldwide and provide for the most weight loss. Others include Biliopnacreatic Diversion with Duodenal Switch, which creates a sleeve stomach and bypasses a decent portion of the small intestine; and Gastric Band, an adjustable, removable band tied around top of stomach to make us feel more full.

#2 – Bariatric surgery is only for people with a BMI >40
Recently updated guidelines from ASMBS-IFSO (two organizational authorities on bariatric surgery) will make surgery much more commonplace over the next few years. They are now recommending it for anyone with BMI >/=35 (down from >40) without any comorbidities, and 30-34.9 (down from >35) for those with comorbidities, including adolescents.

Following suit, the AAP is now recommending bariatric surgery for teenagers as a viable method for weight loss. Along with weight loss medications (such as Wegovy) it’s billed as a “last resort,” but the AAP acknowledges the first line treatments for obesity are not available to most children in America. This means the last resort becomes a viable option quicker than we’d hope.

#3 – Insurance pays for bariatric surgery
Prior to surgery, most insurance companies need proof of blood tests, medical imaging, sometimes routine endoscopy, proof of participation in at least three to six months of weight loss programming that didn’t work, and mental health evaluations – at baseline.

Some insurance does cover the surgery, but not always. It depends on a variety of factors. And if unexpected complications occur, the price may increase – and this is not uncommon.

For example, in a recent interview with Marc Bessler, MD, Director of the Center for Metabolic and Weight Loss Surgery, he reports that about a third of his practice has become taking care of issues with operations that other physicians have performed or revising surgeries to improve side effects like gastric reflux or weight regain.

#4 Weight loss is guaranteed
There are conflicting statistics on how much weight is lost after surgery, even on average. One of the reasons is because some studies measure what’s called “excess weight” using an equation to determine how much extra weight a person is carrying (this excess weight loss is also advertised in commercials for Wegovy). And some studies focus on overall total weight loss.

ASMBS reports patients may lose up to 60-70% of excess weight within a year, and that five years after surgery, an average patients maintain 50% of their excess weight loss. A 2020 research study indicated 15-35% of patients don’t reach their weight loss goals, and that many patients will regain their lost weight after two years. Yet another statistic indicates that 30% will regain most of their weight in five years.

And not only is the weight loss often a gradual process over the first year, but there is typically a lot of loose skin leftover. What most bariatric surgery centers advise is to think of the surgery as a tool, just one of many in the arsenal – it’s not a quick fix.

They tell patients to avoid carbs as much as possible, keep the meal size to six ounces, and exercise regularly. In other words, the instructions are to continue the lifelong dieting pattern that didn’t seem to work for folks to begin with. This can be frustrating.

#5 Complications are rare
While statistics indicate 4% will have chronic complications, what constitutes a complication is not fully defined. Personally, in the short term I have seen gastrointestinal leaks, infections, fevers, nausea/vomiting, and/or intolerance to food. In the long-term, I’ve seen ulcers, hernias, reflux, dumping syndrome (pretty much exactly what it sounds like), and vitamin abnormalities. These are just a few examples.

Studies are conflicting on mental health post-op – some indicate an improvement while others show an increase in depression, binge eating disorders, and alcohol or substance abuse.

#6 People are healthier after getting bariatric surgery
In some ways they are, but here are some other things to consider:

  • Doesn’t it cure diabetes? Bariatric surgery is the most effective way to put Type 2 diabetes into remission, and this occurs in about 75% of patients (though the mechanism is still not fully understood). Unfortunately, remission is not always permanent nor is it a guaranteed result for everyone.
  • Isn’t it a super safe procedure? Bariatric surgery has <1% mortality rate, but studies do show an increase in accidental and suicidal death after bypass.
  • Don’t people go on to live longer lives? People are living longer lives post-op, and that’s a huge deal (some studies indicate by 30-50%). But one of the reasons people get this surgery is because they are denied other surgeries (life-saving heart surgery, or knee surgery, for example) until they make a certain weight. Therefore, it’s not necessarily the surgery or the weight loss that saves lives, but it’s the gatekeeper to the life saving intervention.
  • Doesn’t the surgery prevent absorption of junk food? Altered anatomy changes how all components of food (including the nutrient dense components) are absorbed. A decreased absorption of vitamins and minerals such as iron, calcium, vitamin D, B vitamins, fat soluble vitamins (A,K, and E) can lead to serious deficiencies. Therefore, most patients have to remain on a lifelong vitamin and mineral regimen.

Bariatric surgery is the most effective method for weight loss at this time, but it doesn’t come without serious side effects. Careful review and understanding of the surgical process and insurance coverage, as well as managing expectations post-op, is vital prior to making any decisions about surgical weight loss intervention.

It is important to also remember that we can be healthy at a wide range of sizes, and feeling good about ourselves does not have to align with how thin we are. If thinking more about the rhyme and reason behind bariatric surgery, and its place in our current culture, check out my post on Medical Interventions for Weight Loss

💛 And as always, we love to hear from readers, so please share your comments and questions below!

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  1. Valerie Peery

    Gastric sleeve Best thing I ever did for myself. Went from 300 lbs with insatiable appetite to 195, regained to 230. Gradually went back to 210. Maybe it doesn’t seem like a huge amount but I felt lighter than air. Gradually over 10 years went down to 150, present weight. So glad.