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What is metabolic surgery? Can it help treat type 2 diabetes? Dr Melvin Look, general surgeon at Parkway East Hospital, answers frequently asked questions about metabolic surgery and if it is suitable for everyone.

Last updated on 10 February 2022

What is metabolic surgery?

Metabolic syndrome

Metabolic surgery refers to surgical procedures used in the treatment of metabolic diseases, especially, type 2 diabetes.

Metabolic syndrome is a cluster of disorders of metabolism that tend to occur together, and is caused by obesity, physical inactivity, increasing age and genetics. Metabolic syndrome greatly increases your risk of developing elevated blood sugar (diabetes), elevated blood pressure (hypertension), elevated blood cholesterol and lipids (dyslipidemia) leading to heart disease and stroke.

Diabetes is a medical condition in which the blood glucose levels remain persistently higher than normal. Obesity is one of the most important factors in the development of diabetes.

Is metabolic surgery right for me?

In Singapore, 1 in 3 diabetics are unaware that they have diabetes. Among the diabetics who are aware of their disease, 1 in 3 has poor control of their condition. Persistently elevated blood glucose levels lead to long-term end organ damage to the eyes, kidneys, nerves, heart and peripheral vascular system. This in turn causes blindness, kidney failure, amputation, heart attack and stroke.

Diet and exercise remains the cornerstone in the management of diabetes. Many patients, however, are unable to achieve and maintain a healthy weight, and this in turn can lead to poor control of blood sugar levels despite the use of multiple oral medications and insulin injections.

Metabolic surgery should be considered for all poorly controlled diabetics, especially those who are overweight or obese. As a guideline for Asian patients we usually use a Body Mass Index (BMI) of more than 27 kg/m2.

Diabetic patients who do not want to take lifelong medication and prefer a surgical procedure to reverse diabetes should also consider metabolic surgery.

If you are keen to consider metabolic surgery, you will have to undergo screening procedures to see if you qualify. You must also be willing to make permanent changes to lead a healthier lifestyle.

What are the types of metabolic surgery

Types of metabolic surgery
The more common metabolic surgery operations are the laparoscopic sleeve gastrectomy and the laparoscopic gastric bypass. These are minimally invasive keyhole procedures similar to the weight loss procedures that are commonly done for patients with obesity.

Laparoscopic sleeve gastrectomy

This is a keyhole surgical procedure that coverts the stomach into a long narrow tube about the shape and size of a banana. This limits the amount of food the patient can eat and enhances the effect of intestinal hormones to bring down blood sugar.

Laparoscopic gastric bypass

This is also a keyhole surgical procedure which creates a small egg-shaped pouch in the upper stomach that is then connected to the lower part of the small intestine in a “Y” configuration. Food is diverted by this bypass and is only absorbed in a short segment of the intestines.

What are the benefits of metabolic surgery?

Benefits of a metabolic surgery include:

  • Weight loss. Significant weight loss that is sustained long term can be achieved with metabolic surgery.
  • Improved diabetes control. Marked weight loss from the surgery leads to significant improvement of type 2 diabetes, with remission also possible.
  • Improvements in other obesity-related complications. Improvements can be seen in associated conditions such as heart disease, high blood pressure and high cholesterol, non-alcoholic fatty liver disease, sleep apnoea and asthma.
  • Improvements in quality of life. Weight loss from the surgery also contributes towards generally improving wellbeing and quality of life.

How to prepare for a metabolic surgery?

Prepare for metabolic surgery
You will undergo a detailed consultation to discuss which metabolic surgery procedure is best for you. You will also undergo blood tests, abdominal ultrasound and gastroscopy to ensure that you are suitable for metabolic surgery. Your surgeon will lead a multi-disciplinary team of dieticians, physiotherapists and other medical specialists to ensure that all associated medical problems are managed in the perioperative period.

What is the recovery process for metabolic surgery?

Surgery is performed under general anaesthesia and takes about 2 hours. You will be put on a liquid diet for a few days better progressing to soft foods. Most patients will stay in hospital for 3 – 5 days. You will be mobilising the day after surgery and the majority of patients will be back to normal activities and exercise after about 2 weeks.

What are the side effects & risks of metabolic surgery?

Metabolic surgery side effects and risks
Metabolic surgery is a very safe operation with a proven long-term track record. The main risks are in the first few days after surgery due to complications such as bleeding and leakage from staple line, infections and medical problems such as respiratory difficulties, deep-vein thrombosis, and adverse reactions to anaesthesia.

You will be guided after surgery to institute lifelong changes to your diet and lifestyle. Long-term complications are rare but weight regain is possible if you persistently overeat.


Article contributed by Dr Melvin Look, general surgeon at Parkway East Hospital


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Metabolic surgery: A powerful solution or a last resort? (2017, June 07) Retrieved December 29, 2021, from https://diabetes.medicinematters.com/metabolic-surgery/type-2-diabetes/metabolic-surgery-a-powerful-solution-or-a-last-resort-/12343792

Bariatric-metabolic surgery: A guide for the primary care physician. (2017, July) Retrieved December 29, 2021, from https://www.racgp.org.au/afp/2017/july/bariatric-metabolic-surgery-a-guide-for-the-primar

Look Chee Meng Melvin
General Surgeon
Parkway East Hospital

Dr Melvin Look is a general surgeon practising at Parkway East Hospital, Singapore.