Gastric bypass surgery Singapore: An effective weight loss solution?

Obesity is a serious condition. Those with obesity often have a series of medical conditions, such as sleep apnea, cancers and cardiovascular diseases. Worldwide, there are about 2.8 million obesity-related deaths every year.

At a fundamental level, increasing physical activity and consuming less calories would naturally lead to weight loss. But eating behaviour and our ability to lose weight is also driven by genetics, hormones and neural circuits — so thinking that combating obesity with just eating less is over simplifying the matter. 

Over the years, studies have shown that gastric bypass surgery or any weight loss surgery in general produced greater and more sustainable weight loss results. Coincidentally, these surgeries also demonstrated a higher remission of obesity-related conditions like type 2 diabetes and metabolic syndrome. 

Is gastric bypass surgery really a permanent and effective weight loss solution? Let’s find out more.

What is gastric bypass surgery?

Gastric bypass surgery is a procedure where surgical changes are made to your stomach and digestive system to limit how much food you consume, how nutrients are absorbed or both. Gastric bypass surgery is a major procedure that’s almost permanent and usually requires long-term adjustments to your lifestyle and diet. 

As with all major surgeries, gastric bypass surgery carries its own risks and thus is only recommended for severely obese patients who cannot lose weight through traditional measures such as diet and exercise.

Guidelines to qualify for gastric bypass surgery in Singapore

Not everyone can qualify for this procedure if they want to lose weight; you need to meet certain medical guidelines.

In general, gastric bypass surgery is an option if:

  • Your efforts to lose weight have been successful despite following a diet and exercise plan 
  • You have a body mass index (BMI) of 40 or higher 
  • You have a BMI of 35 or more together with weight-related health conditions, such as severe sleep apnea, type 2 diabetes and high blood pressure 
  • You are a teenager who have undergone puberty and meet the above requirements

Apart from these requirements, most patients will likely go through an extensive screening process to determine their eligibility. This evaluation will determine if gastric bypass surgery is right for you, if the benefits of the surgery outweigh the potentially serious risks that come with it, and if you’re medically ready to undergo such a procedure. 

Your medical team will consider:

Your weight and eating history
Diet attempts, exercise regimen, weight trends, stress level, time constraint, motivation are some of the factors that will be reviewed

Your medical condition
Some medical conditions may increase the risks associated with having gastric bypass surgery or may be worsened by the surgery, including liver disease, nutritional deficiencies, blood clots, heart problems and kidney stones. The team will also study what medication you take and if you smoke and drink. You might also be evaluated for sleep apnea.

Your psychological status
The presence of mental health conditions may make it difficult to sustain the health benefits of gastric bypass surgery. They may contribute to obesity too. These conditions include anxiety disorders, binge-eating disorders, schizophrenia and major depression. While mental disorders may not entirely prevent you from having gastric bypass surgery, your doctor may first want to ensure that any significant sources of stress are appropriately managed.

Your attitude and motivation
Gastric bypass surgery is not a free and easy pass for weight loss. Are you willing and able to follow through with the recommendations provided by your doctors, as well as stick to a diet and exercise routine?

Gastric bypass surgery procedure in Singapore

How is gastric bypass surgery done in Singapore?

Gastric bypass surgery is often done through a laparoscopic or keyhole technique. It is also called  Roux-en-Y gastric bypass. 

Through this procedure, a small stomach pouch is created by “bypassing” or removing most of your stomach and the first part of your small intestine. This allows food to be directed down the path of the small intestine, which allows the patient to eat less. The length of intestines left to process calories is also shorter, reducing the number of calories and nutrients absorbed, thus leading to weight loss.

How much weight can a patient lose?

Gastric bypass surgery can help lose about 65 percent of excess weight over 6 months to a year. With proper diet and exercise, this weight loss can be sustained even after 10 to 15 years. 

Most patients experience a better quality of life, and most of their obesity-related issues improve or resolve after one year.

How will life be like after gastric bypass surgery in Singapore?

Since you can only eat a small amount of food, you will feel full and satisfied more quickly. Most patients can only eat about 25 percent of what they used to eat. Weight loss down the road will be more sustainable, as the feeling of hunger in dieting will not be present. 

Following surgery, sugary and fatty foods are best avoided as they will be poorly tolerated by your body. If consumed, you may experience some abdominal discomfort, palpitations and nausea. 

Your doctor or nutritionist will prescribe multivitamins and supplements that are extremely important and must be taken to ensure you get in enough vitamins and nutrients. 

It’s important to not overeat after surgery your pouch can stretch over time, causing you to eat more and regain back the weight you lost.

Are there any side effects?

While side effects are rare, they include: 

  • Vitamin and nutritional deficiencies 
  • Acid reflux 
  • Increased sensitivity to alcohol 
  • Stomach ulcers 
  • Bowel obstruction 
  • Infection 
  • Blood clots 
  • Intestinal leaks 

In the long term, the weight you lose may bounce back if you do not stick to the recommended lifestyle changes, including eating healthier and exercising regularly. Surgery alone is not the answer. You need to be prepared to make lifestyle changes in order to benefit from gastric bypass surgery.


  1. Cummings, D. E., Overduin, J., & Foster-Schubert, K. E. (2004). Gastric Bypass for Obesity: Mechanisms of Weight Loss and Diabetes Resolution. The Journal of Clinical Endocrinology & Metabolism, 89(6), 2608–2615.
  2. Liakopoulos, V., Franzén, S., Svensson, A.-M., Miftaraj, M., Ottosson, J., Näslund, I., Gudbjörnsdottir, S., & Eliasson, B. (2019). Pros and cons of gastric bypass surgery in individuals with obesity and type 2 diabetes: nationwide, matched, observational cohort study. BMJ Open, 9(1), e023882.