Gastric bypass is often the best type of bariatric surgery for type 2 diabetes, but other options like sleeve gastrectomy or duodenal switch may work better, depending on your health needs.

Bariatric surgery is a procedure that changes your digestive system to help with weight loss. It may involve reducing the size of your stomach or rerouting your digestive tract.

Doctors often recommend it for people with severe obesity, especially if you have type 2 diabetes, a chronic condition that affects how your body uses blood sugar.

This article will discuss which bariatric surgery is best for type 2 diabetes, including its success rate, risks, outlook, and other weight loss options.

Gastric bypass is the best bariatric surgery for type 2 diabetes. It helps lower blood sugar the most and can even lead to remission for some people, according to research.

Remission refers to when your blood sugar stays in a healthy range without the need for diabetes medication. According to the American Diabetes Association (ADA), for most people, this means:

  • Fasting blood sugar: below 100 mg/dL
  • A1C level: below 6.5%

A 2024 review of studies found that people with type 2 diabetes who had Roux-en-Y gastric bypass had better long-term blood sugar management than those who had other types of bariatric surgery, such as sleeve gastrectomy.

However, each type of bariatric surgery has pros and cons. Depending on your health needs, a healthcare professional can help you choose the safest and most effective option.

There are four main types of bariatric surgery:

  • Roux-en-Y gastric bypass (RYGB): In this surgery, a doctor creates a small pouch in your stomach and reroutes part of your small intestine. This limits how much you can eat and may change hormones that affect appetite and blood sugar management.
  • Sleeve gastrectomy: This procedure removes most of your stomach, leaving a small “sleeve.” It helps you eat less and affects gut hormones linked to hunger and blood sugar management, leading to weight loss.
  • Adjustable gastric banding: A doctor places a band around the upper part of your stomach to create a small pouch. Doctors perform this surgery less often today because it leads to less weight loss and carries a higher risk of complications.
  • Biliopancreatic diversion with duodenal switch (BPD/DS): This complex surgery removes part of the stomach and reroutes the intestines. It often leads to the most weight loss, but also has the highest risk of nutrient deficiencies.

Bariatric surgery can offer several benefits for people with type 2 diabetes, including:

  • Improving how your body uses insulin and lowering your A1C levels (average blood sugar).
  • Supporting long-term weight loss, which can help control blood sugar.
  • Reducing your need for diabetes medications and, in some cases, helping you reach remission.
  • Lowering blood pressure and cholesterol reduces the risk of heart disease.
  • Boosting energy, mood, and overall quality of life after weight loss.
  • Your BMI is 35 or higher.
  • You have a BMI of 30 or higher with trouble managing diabetes medications and lifestyle changes.
  • You’re committed to making long-term changes after surgery, including diet, exercise, and follow-up care.

Doctors also consider your age, overall health, and mental readiness before recommending surgery.

Like any surgery, bariatric surgery has some risks to consider if you have type 2 diabetes.

These risks may include:

  • Surgical complications like infection, bleeding, blood clots, or leaks in the stomach or intestines.
  • Nutrient deficiencies, since some surgeries reduce how much your body can absorb vitamins and minerals.
  • Digestive problems, such as dumping syndrome, where food moves too quickly through the digestive tract. This can cause nausea, dizziness, or diarrhea.
  • Low blood sugar (hypoglycemia), especially if your body becomes more sensitive to insulin after surgery, but you continue using the same medications.
  • Weight regain over time if you don’t follow the recommended diet, exercise, and follow-up care plan.

​​Bariatric surgery may not be right for every person. You may need to avoid it if you:

In these cases, other treatments may be more suitable for you.

If you’re not a candidate for bariatric surgery or prefer nonsurgical options, there are other ways to lose weight and manage blood sugar levels. These include:

  • Lifestyle changes: Eating a diabetic diet and staying active can help lower blood sugar and improve your health.
  • Medications: Certain medications, like GLP-1 receptor agonists such as semaglutide (Ozempic, Wegovy) or liraglutide (Saxenda, Victoza), can support weight loss and blood sugar management.
  • Behavioral programs: Working with a dietitian or joining a weight-loss program can help you build healthy habits and stay consistent.

The outlook is often positive. Many people:

A 2024 study followed people with type 2 diabetes for over 10 years. Those who had a gastric bypass maintained lower A1C levels and had fewer diabetes-related complications.

Gastric bypass is often the best bariatric surgery for type 2 diabetes. However, other types of bariatric surgery, such as sleeve gastrectomy, may work better, depending on your health.

If you are considering bariatric surgery, consider talking with a healthcare professional to explore your options. They can also help you decide which procedure fits your needs best.