Gastric Sleeve Surgery vs. Gastric Bypass

Uses, Benefits, Side Effects & More

When diet and exercise alone are ineffective at keeping weight loss off long term, your healthcare provider may recommend weight loss surgery, also known as bariatric surgery.

People who are considering weight loss surgery have several options. Two of the most common options are gastric sleeve surgery and gastric bypass surgery. Despite having the same goal, there are key differences between the two.

This article will discuss the differences between gastric sleeve surgery and gastric bypass surgery to help you decide which one may benefit you. However, it's important to speak with your healthcare provider to discuss your options.

Surgeons working in an operating room

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What to Know About Gastric Sleeve Surgery

Gastric sleeve surgery, also known as vertical sleeve gastrectomy, involves removing a portion of the stomach to help you take in less food. It is the most popular bariatric procedure worldwide.

How Does It Work?

Gastric sleeve surgery works by removing the majority of the stomach. The new, smaller banana-shaped stomach holds less and, thus, reduces your total calorie intake.

The procedure also removes the upper, rounded portion of the stomach called the fundus, where most of the "hunger hormone" ghrelin is produced. By reducing ghrelin levels, the surgery can also promote fullness and decrease hunger.

It is often recommended to treat obesity in people with a body mass index (BMI) over 40. Other people who are considered for gastric sleeve surgery include:

When paired with the recommended lifestyle and dietary changes, a person can expect to lose 60%–70% of excess body weight within 12 to 18 months following surgery.

How Gastric Sleeve Surgery Is Performed

Gastric sleeve surgery is a minimally invasive procedure usually done using a laparoscope (a long, thin tube with a light and camera attached). The procedure itself takes between 40 and 70 minutes. Before surgery, you will be placed under general anesthesia, in which you will be unconscious. You will not feel any pain or remember anything.

Two to five small incisions will be made in your abdomen, allowing the laparoscope and other surgical tools to pass through.

Next, the surgeon will remove the majority (roughly 80%) of your stomach. This is performed by using surgical staplers to seal and divide the majority of the stomach, creating a long, narrow tube or "sleeve."

You will likely have to stay in the hospital for at least one day following surgery. The total gastric sleeve recovery time is approximately two to four weeks.

Side Effects

The gastric sleeve is considered a safe bariatric procedure and is endorsed by the American Society for Metabolic and Bariatric Surgery (ASMBS).

In addition to standard risks of surgery and general anesthesia, possible disadvantages or complications of gastric sleeve surgery include:

  • Heartburn or reflux
  • Making existing heartburn or reflux worse
  • Weight regain
  • Loose or saggy skin (from weight loss)
  • Vitamin and nutrient deficiencies from insufficient food intake
  • Stricture formation (narrowing of the sleeve)

Prices and Where to Get It

Gastric sleeve surgery can cost around $15,000, but the surgery is covered by most insurance plans.

It can be difficult to predict your costs for any surgery, including gastric sleeve surgery, until you meet with your healthcare provider. Once your provider has recommended a treatment plan, contact your insurance company to determine how much it will cost.

When searching for a local qualified surgeon to perform your gastric sleeve surgery, you can ask your primary care provider for a referral to a weight loss surgeon. Alternatively, you can also find a surgeon in your area by visiting the ASMBS website and searching under "Find a Provider."

What to Know About Gastric Bypass

Gastric bypass, also referred to as Roux-en-Y gastric bypass, is the gold standard weight loss procedure. It aids in weight loss by altering how the body processes and digests food.

However, it has a slightly higher complication risk and a longer recovery time than gastric sleeve surgery.

How Does It Work?

Gastric bypass works by essentially shrinking the size of your stomach, making it difficult to consume large amounts of food, and changing how food is digested. It also alters hormones in the gut to help you feel fuller longer.

It's typically recommended for those with a BMI over 45 who have attempted other weight loss methods without success.

Most people can expect to lose 60%–80% of excess body weight within the first 12 to 18 months following surgery.

How Gastric Bypass Is Performed

Similar to the gastric sleeve, you will be placed under general anesthesia for surgery. The total procedure takes two to four hours to complete.

The procedure can be performed laparoscopally or as an open surgery, in which a large incision is made to cut open your abdomen.

Gastric bypass surgery involves creating a small, egg-sized pouch from the upper portion of the stomach and connecting it directly to the small intestine. This allows your food to bypass the rest of your stomach and the upper part of your small intestine.

Because many nutrients are absorbed in the beginning of the small intestine, gastric bypass results in fewer calories absorbed from the foods you eat.

Most people stay in the hospital for two to three days following surgery. Total gastric bypass recovery time is three to six weeks.

Side Effects

Gastric bypass surgery is also considered to be a safe bariatric procedure and is endorsed by the ASMBS.

However, because gastric bypass surgery is more complex than gastric sleeve surgery, it has more potential side effects and risks. These include:

What Is Dumping Syndrome?

Dumping syndrome is characterized by bloating, diarrhea, nausea, dizziness, and abdominal cramps following a meal. It happens when the food you eat is "dumped" from your stomach pouch into your small intestine undigested.

It can occur in at least 15% of people who have had a portion of their stomach removed for any reason. Certain foods like sugar tend to worsen the condition. Treatment involves making dietary changes.

Prices and Where to Get it

Gastric bypass can cost around $20,000. However, as with other bariatric surgeries, insurance often covers gastric bypass as long as you meet specific requirements.

If you have insurance, it's important to contact your insurer directly to discuss how much you will owe.

To find a bariatric surgeon in your area, visit the ASMBS website and search under "Find a Provider."

Your primary care provider may also be able to refer you to a qualified bariatric surgeon.

Which Treatment Is Best for You

The type of bariatric surgery that is best for you depends on:

  • Underlying health conditions
  • Your current weight
  • Your medical history
  • How much weight you need to lose

When you visit with your bariatric surgeon, they will be able to discuss the pros and cons of both treatment options to find out which is best suited for you.

Can Gastric Sleeve Surgery and Gastric Bypass Be Used Together?

In some circumstances, often when a person has a substantial amount of weight to lose, a gastric sleeve may be the first step in a two-step bariatric surgery process.

Gastric sleeve is commonly recommended in people with a BMI over 60 who are at risk for major complications from surgery. Those deemed a candidate will have gastric sleeve surgery, allowing them to achieve a weight loss of 80–100 pounds.

After eight to 12 months, their sleeve will be transformed into a formal gastric bypass for more substantial, long-term weight loss.

Coping With Side Effects

During the first few weeks after surgery, it's normal to experience nausea, vomiting, decreased appetite, and fatigue. You may also notice changes in bowel patterns, gas, and postsurgical pain.

To minimize uncomfortable side effects, it is important to stick with your treatment plan, stay in contact with your bariatric team, and closely follow the diet and hydration guidelines provided to you.

Your healthcare provider will likely prescribe prescription pain medications to help you stay comfortable. Other medications are also available to help alleviate the discomfort associated with bariatric surgery. These include:

  • Over-the-counter (OTC) pain medications, such as Tylenol (acetaminophen)
  • Antacids for acid reflux, heartburn, and indigestion
  • Stool softeners for constipation
  • Proton-pump inhibitors such as omeprazole (Prilosec)
  • Probiotics promote the growth of beneficial gut bacteria

NSAID Warning

The use of nonsteroidal anti-inflammatory drugs (NSAIDs) after bariatric surgery can increase your risk of stomach ulcers. Examples of NSAIDs include aspirin, Advil (ibuprofen), and |Aleve (naproxen).


Gastric sleeve surgery and gastric bypass surgery are both safe, effective types of weight loss surgery. Gastric sleeve surgery is minimally invasive and involves removing around 80% of your stomach. Gastric bypass, on the other hand, is a two-step procedure that involves attaching a small pouch of the stomach to the second part of your small intestine to allow food to bypass the stomach.

Both come with benefits and risks. Gastric sleeve surgery is more popular and generally has fewer side effects because it is a less complex surgery. However, those who have a significant amount of weight to lose may benefit more from gastric bypass.

If you are considering weight loss surgery, consider talking with your primary care provider. They can help you decide if you are a good candidate and, if so, refer you to a qualified bariatric surgeon.

A Word From Verywell

Making the decision to have weight loss surgery can be difficult, and deciding which procedure to have can add to the confusion and worry. Both are highly effective procedures that can result in long-term weight loss if you follow and implement the recommended diet and lifestyle changes. The good news is that your healthcare team will be there to guide you and support you every step of the way.

Frequently Asked Questions

  • Is the gastric sleeve better than gastric bypass?

    Generally speaking, the gastric sleeve comes with fewer complications than gastric bypass. However, if you have a significant amount of weight to lose, the benefits of gastric bypass can outweigh the side effects.

  • Do you lose weight faster with the sleeve or bypass?

    Gastric bypass will produce faster weight loss compared to the gastric sleeve. The majority of people who have gastric bypass will lose as much as 80% of their excess weight within the first 12 to 18 months.

  • What are the downsides of gastric sleeve?

    Although gastric sleeve can be an effective weight loss tool, it can cause nutrient deficiencies, bleading, and leakage.

13 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
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By Lindsey DeSoto, RD, LD
Lindsey Desoto is a registered dietitian with experience working with clients to improve their diet for health-related reasons. She enjoys staying up to date on the latest research and translating nutrition science into practical eating advice to help others live healthier lives.