Weight loss surgery, also called bariatric surgery, is seen as a treatment for type 2 diabetes and there is strong evidence it is an effective way to put your type 2 diabetes into remission long term.

Bariatric surgery changes the way the digestive system works in ways that are beneficial for people with type 2 diabetes. It involves bypassing or reducing the size of your stomach so you feel fuller sooner and eat less calories and lose weight. This type of weight loss surgery is sometimes also called metabolic surgery.

Evidence shows that bariatric surgery is a very effective treatment option for some people with type 2 diabetes and can be cost-effective. (Source: NHS)

Bariatric surgery improves control of diabetes through both weight-dependent and weight-independent actions. Weight dependent actions like insulin sensitivity and decreases inflammation and weight-independent actions like hormonal changes, such as increased GLP-1 secretion, which enhances insulin production and helps regulate blood sugar levels. These various mechanisms help explain the difference between individuals treated surgically vs. medically. They also explain differing effects of various bariatric surgery procedure types. Understanding how surgery affects diabetes will help optimise utilisation of the surgical procedure for both disease prevention and treatment.

How Does Bariatric Surgery Resolve Diabetes?

Obesity and diabetes are among the most concerning health problems that exist today. In India, an estimated 135 million individuals are affected by obesity, and upwards of 101 million Indians have diabetes. Both are treated with diet, exercise and medications but usually yield poor long-term results. Treatment with lifestyle modification usually results in progressive weight gain and worsening control of diabetes. Medical treatment of diabetes has the goal of delaying the onset of serious complications such as heart attack, blindness, stroke, amputation and kidney failure.

Recent studies and analysis have shown that bariatric surgery can lead to weight loss in patients who are affected by obesity and have Type 1 diabetes. Bariatric surgery may show significant improvement in insulin requirements and HBA1c in patients who have Type 1 diabetes. These favourable metabolic improvements from bariatric surgery may help with the medical management of Type 1 diabetes for patients with obesity. How is this possible? Well, it turns out that our gastrointestinal tract (stomach and small intestine) do more than just digest our food.

Current research supports the belief that the gastrointestinal tract is important for controlling blood sugar and that bariatric surgery is capable of both preventing and treating diabetes. This improvement in diabetes often occurs before the patient has had any sign of weight loss. After surgery, changes in intestinal hormones, bile metabolism and gut bacteria all instantly appear to play a role in getting rid of diabetes.

Mechanism of Diabetes Remission after Bariatric Surgery

While the gastrointestinal tract is known to produce over 100 different hormones, the precise mechanism by which it leads to diabetes remission remains unclear. However, several factors have been identified as contributors, including:

• Fasting
• Stomach
• Upper and lower sections of the small intestine

These segments of the intestinal tract help resolve diabetes following bariatric surgery by reducing appetite-stimulating hormones, bypassing sections so they no longer “sense food,” and quickly delivering food to the lower intestine after meals.

Is Bariatric Surgery a Permanent Cure for Type 2 Diabetes?

Like we mentioned before, weight loss surgery has significant potential to send a patient's type 2 diabetes into remission. That doesn't mean that their diabetes is cured, but rather that it is controlled to the point where they no longer need to take medication to stabilise their blood sugar levels. However, their symptoms may come back and medication may be needed if a patient regains the lost weight.

In some cases, it may be possible for patients to achieve a complete resolution of their type 2 diabetes. We've also observed this happening with some of our patients. This is more likely the case for those who were diagnosed with diabetes less than 5 years ago and were not taking blood sugar medication prior to bariatric surgery.

What Weight Loss Surgery Options are Available?

At MASSH Hospital, patients with type 2 diabetes are offered three types of weight loss surgery, based on the doctor's recommendation after a thorough review of their medical history and current health status:

• 3D Laparoscopic Gastric Bypass reduces your stomach size and reroutes the gastrointestinal tract so that food bypasses most of the stomach and part of the small intestine, reducing the number of calories the body can absorb.
• 3D Laparoscopic Sleeve Gastrectomy removes a portion of the stomach, making the stomach smaller and narrower. Gastric sleeve procedure decreases the body's production of appetite-increasing hormones.
• 3D Laparoscopic Roux-en-Y procedure creates a small pouch from the upper part of the stomach and directly connects to a portion of the small intestine, bypassing a large part of the stomach and the first section of the intestine (duodenum). This dual approach limits food intake and reduces calorie and nutrient absorption. It also leads to significant hormonal changes that help with appetite control and improvement in type 2 diabetes.

All these surgical procedures are highly effective and can lead to significant weight loss. There are benefits and risks to every surgery and either one surgery isn't universally better than the other. In our practice, patients and the doctor discusses their individual needs and preferences to make a personalised recommendation on which surgery is best for them.

When is Surgery Recommended?

Bariatric surgery is available at MASSH Hospital for people who meet certain criteria. These can include:

• You have a BMI of 40 or more, or a BMI between 35 and 40 and an obesity-related condition that might improve if you lost weight (such as type 2 diabetes or high blood pressure)
• You've tried all other weight loss methods such as dieting and exercise but have struggled to lose weight or keep it off
• You agree to long-term follow-up after surgery such as making healthy lifestyle changes and attending regular check-ups 

MASSH Hospital recommends that if adults with type 2 diabetes fulfil certain criteria they should be offered an assessment for bariatric surgery to see whether it is suitable. If you have been diagnosed with type 2 diabetes in the past 10 years, the guidance states that you should be considered or offered a quicker assessment, depending on your BMI.

Life After Surgery

Immediately after the operation, you will be put on a liquid or soft diet. Gradually, you will move to a balanced diet that you will need to stay on for the rest of your life. You will probably also have to take vitamin and mineral supplements. Once you have recovered from surgery, you will be advised to follow an exercise programme for the rest of your life. You will also need regular follow-up appointments to check how things are going.

Conclusion

Bariatric surgery is a highly effective treatment for type 2 diabetes, offering the potential for long-term remission and improved metabolic health. By altering the structure and function of the digestive system, it helps regulate blood sugar levels through both weight loss and hormonal changes. While not a guaranteed cure, it can significantly reduce or eliminate the need for diabetes medications, especially in patients diagnosed early. With proper follow-up care, lifestyle changes, and medical guidance, bariatric surgery can transform the lives of individuals struggling with obesity and diabetes.

For those considering this life-changing procedure, MASSH (Minimal Access Smart Surgery Hospital) is a highly recommended centre for bariatric surgery, known for its advanced 3D laparoscopic techniques, experienced surgical team, and comprehensive post-operative care. The SMART Weight Loss Programme at MASSH includes personalised surgical planning, nutritional guidance, physiotherapy support, psychological counselling, and regular follow-ups to ensure safe, sustainable, and long-term weight loss success.

Frequently Asked Questions

1. Will I need to have tests before surgery?
Yes. Before bariatric surgery, you will need a series of tests and evaluations to ensure you are a suitable candidate. These may include blood tests, chest X-ray, ECG, nutritional assessment, psychological evaluation, and possibly an upper GI endoscopy or abdominal ultrasound. These help assess your overall health and identify any conditions that need to be managed before surgery.

2. How long does the surgery take?
The duration of bariatric surgery depends on the type of procedure. On average:

• 3D Laparoscopic Sleeve Gastrectomy takes about 45–60 minutes
• 3D Laparoscopic Roux-en-Y Gastric Bypass typically takes 2 hours
• 3D Laparoscopic Mini Gastric Bypass usually takes 70-90 minutes

Recovery from anesthesia and post-operative monitoring adds additional time in the hospital.

3. What is pre-operative nutrition?
Pre-operative nutrition involves a specific diet plan prescribed before your surgery to prepare your body. The goal is to reduce liver size, improve surgical access, decrease complications, and improve overall outcomes. It typically includes high-protein, low-carb meals and may shift to a full or partial liquid diet closer to the surgery date.

4. Why do I need to make changes in my diet and lose some weight before surgery?
Losing weight before surgery helps reduce fat around the liver and abdomen, making the procedure safer and technically easier. It also demonstrates your commitment to the lifestyle changes needed after surgery and lowers the risk of surgical complications, such as infections or anesthesia-related issues.

5. What is the pre-op liquid diet?
The pre-operative liquid diet is a short-term, medically guided diet you follow 1–2 weeks before surgery. It typically includes:

• Protein shakes
• Clear broths
• Sugar-free drinks
• Low-fat dairy or non-dairy alternatives
• Water

This diet shrinks the liver and reduces intra-abdominal fat, improving surgical safety and visibility.

6. Will you remove my gallbladder during the procedure?
The gallbladder is not routinely removed during bariatric surgery. However, if you have gallstones, gallbladder disease, or a high risk of developing issues post-surgery, your surgeon may recommend removing it during the same procedure. This decision is made based on your medical history and imaging results before surgery.