Your Guide To Gastric Sleeve Risks

Your Guide To Gastric Sleeve Risks

One of the most popular weight-loss surgeries is a sleeve gastrectomy. Also called a vertical sleeve, this procedure is the most common bariatric procedure performed worldwide. In a gastric sleeve, the surgeon removes about 80% of the volume in your stomach. Your stomach becomes a slim tube with these surgical alterations that are a fraction of its original size. This surgery helps you lose weight because it restricts the volume of food you can eat and alters your digestive hormones. Like any other surgery, there are gastric sleeve risks you must take into consideration.

The Obesity Epidemic

The rates of obesity have accelerated exponentially in the past few decades. According to the CDC, 42.4% of Americans are obese. One of the biggest risk factors for being obese is developing other health conditions like:

  • Type 2 diabetes
  • Depression
  • Osteoporosis
  • Stroke
  • Heart disease
  • Certain types of cancer

Not to mention, obesity is a costly disease, where people spend more money to cover health-related costs than people who are of normal weight.

Your risk factors for other diseases like stroke and heart disease increase if you are overweight or obese.

There are few ways one can approach extreme weight loss. Strict dieting and exercise can work for a short time. However, because of the physiological and psychological strains obesity places on your body, it is difficult to achieve your weight goals with diet and exercise alone. Patients and their doctors often turn to weight loss surgery because this type of weight loss usually requires physiological shifts inside your body.

Meeting the Criteria for Sleeve Gastrectomy

You have to check a few boxes to be eligible for a gastric sleeve:

  1. Your BMI must be greater than or equal to 40, or you must be 100 pounds overweight.
  2. Your BMI must be greater than or equal to 35 with at least one or more obesity-related complications like high blood pressure, fatty liver disease, sleep apnea, or type 2 diabetes.
  3. You must demonstrate failed attempts at weight loss in the past through other efforts like diet and exercise.

There are also other factors your doctor will need to discuss with you before scheduling you for surgery. First and foremost, you must be willing to accept that you will need to make significant lifestyle changes starting even before surgery. You must demonstrate a willingness to adopt a healthier lifestyle, which includes changing your diet and eating habits, making changes to your behavior, and staying on top of other medical conditions. Being committed to making these changes can help decrease the risks of gastric sleeve surgery.

It is important to be committed to adopting a healthy lifestyle before signing up for weight loss surgery.

Gastric Sleeve Risks and Benefits

Like all surgeries, there are risks. However, people who are seeking gastric sleeve surgery have the added risk of being overweight. Obesity is a well-known surgical risk factor because it can add to complications during surgery. Yet, bariatric surgery teams are trained to avoid these risks during surgery.

Gastric Sleeve Risks In the Post-Op Period

After surgery, your health care team will immediately monitor you for complications from surgery and anesthesia, including breathing problems, perforations, infections, and bleeding. You will need to stay in the hospital for one night, at a minimum.

Within the first 3 months, you may encounter any of the following risks and side effects:

  • Nausea and vomiting
  • Difficulty tolerating certain foods
  • Acid reflux
  • Dehydration

Long-term risks of gastric sleeve surgery include:

  • Nutritional deficiencies
  • Ulcers
  • Strictures
  • Failure to sustain weight loss or gaining weight

Certain gastric sleeve risk factors are less common than others. Let’s dig into some of the more common risk factors.

Difficulty Tolerating Certain Foods

Your palette and preferences will likely change after surgery. One of the reasons this change occurs is because surgery alters your gut hormones, which often curbs your interest in food in general. However, one of the biggest factors is that your body cannot digest certain foods after surgery.

Sugary foods are hard to tolerate after gastric sleeve surgery and can cause unpleasant side effects like dumping syndrome.

Foods that are high in sugar or fat, and fried foods, are challenging to tolerate. Likewise, foods that cause bloating can make you feel quite miserable. Often, people experience nausea, vomiting, or diarrhea with these foods, which makes them less appealing, especially in the first few months after surgery. This is not to say you won’t crave sweet treats or drive-thru food one day, but its appeal will likely wear off if you have unpleasant symptoms after eating these items.

Nutritional deficiencies

One of the more severe risks, although uncommon, is malnutrition. Because you cannot tolerate more than a few tablespoons of food at a time, there is an extreme risk of having nutritional deficiencies.

Some of the most common post-bariatric nutritional deficiencies include:

  • Vitamin B12
  • Folate
  • Zinc
  • Iron
  • Copper
  • Calcium
  • Vitamin D

Aside from the above nutrients, there is also concern over your ability to get enough protein. This macronutrient is vital for supporting your entire body. Therefore, most of your meals will need to contain protein to help you meet your daily requirements. The American Society for Metabolic and Bariatric Surgery (ASMBS) recommends that bariatric surgery patients get between 60-100 grams of protein each day.

All bariatric surgery patients should work with a nutritionist to learn about the nutritional guidelines for gastric sleeve patients, develop an eating plan, and make sure they are on the right vitamin schedule.


As one of the most common risk factors in the early post-op period, dehydration can also occur anytime after gastric sleeve surgery. Because you have such limited space for eating and drinking, people can forget to drink, especially because you can’t “chug” water after surgery. Rather, you have to take small sips throughout the day and space them out from mealtimes.

The ASMBS recommends post-WLS patients drink at least 64 fluid ounces of water daily. The best way to measure your daily intake is to keep a water bottle with you that lets you measure your intake.

It is important to stay diligent with drinking plenty of water each day.

Failure to Lose Weight

You will lose some weight with this procedure. However, there is no guarantee that you will meet your weight goals and not re-gain weight. Sometimes, people hit a weight plateau that they cannot surpass. It is not uncommon for people to stall in their weight loss journey and consider further strategies, like changing their diet or exercise routine, and even another bariatric procedure like gastric bypass.

Benefits of Gastric Sleeve Surgery

A sleeve gastrectomy would not be a popular weight loss solution if it did not have obvious benefits.

Weight Loss

Perhaps the greatest benefit is that it does help people lose weight. Because it successfully restricts that amount of volume you can take in, people often see the pounds fall away. Yet, weight loss does not come without significant effort and dedication to your weight loss goals.

Improves Other Health Conditions

Aside from losing weight, one of the main benefits of this surgery is that it can help make your obesity-related conditions more manageable. In some cases, it may even treat these conditions (like type 2 diabetes). Because surgery can improve other health conditions, you may also find that you do not need to spend as much money on health-related costs.

Boosts Your Quality of Life

Finally, weight loss can add immeasurable value and positivity to your life. Although your relationships with certain people may change (especially if you a person is not supportive of your weight loss goals), people generally feel more confident, more capable, and free without the baggage of excess weight.

Losing weight can help boost your overall quality of life.

If you are considering weight loss surgery, the best place to turn is a trusted bariatric surgeon. Learn as much as you can about your options, connect with other people who have had WLS surgery, and do your own research to help you determine if the benefits outweigh the risks of gastric sleeve surgery.

Julia Rae Walker, RN, BSN, BA


Julia is an experienced critical care nurse with a background in pediatric and adult patient populations. Her passion is helping patients maximize their quality of life.

Gintas Antanavicius, MD, FACS, FASMBS

Medical Reviewer

Dr. G is a co-founder of BariBuilder. A US-based expert surgeon with over 10 years of bariatric experience, he regularly publishes research in medical journals like SOARD, Obesity Surgery, etc.