Weight loss surgery for type 2 diabetes

Weight loss surgery, also called bariatric surgery, can be a very effective way of losing weight and putting type 2 diabetes into remission. It involves bypassing or reducing the size of your stomach — so you feel fuller sooner and eat less. This type of surgery is known as bariatric surgery or metabolic surgery.

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

Bariatric surgery and diabetes

For people with diabetes, bariatric surgery isn’t just about weight loss. It is now seen as an actual treatment for type 2 diabetes, and the weight loss becomes a bonus. It helps your body to produce and use insulin more efficiently and effectively.

Research has shown people’s blood sugar levels dropping to below the diabetes range soon after surgery, even when they haven’t lost weight. Because of this, most people who have bariatric surgery have their diabetes medications stopped soon afterwards. 

Bariatric surgery changes the way the digestive system works, in ways that are beneficial for people with type 2 diabetes. It can:

• make you feel full more quickly, which means you eat less
• change how the hormones in your gut work, which in turn affects how your body makes insulin
• increase the amount of bile acids that your body makes – these make your body more sensitive to insulin
• improve the way your body uses insulin, leading to lower blood sugar levels.

One study found that almost a third (30.4%) of people who had surgery were in remission after 15 years. 

Types of bariatric surgery 

There are different types of surgical procedures, including a gastric band, gastric bypass or a sleeve gastrectomy.

• Gastric band – a band is placed around the upper part of the stomach, which means that you won’t have to eat so much in order to feel full.
• Gastric bypass – the digestive system is re-routed to bypass most of the stomach except for a small pouch at the top. You will feel fuller sooner and absorb fewer calories from your food.
• Sleeve gastrectomy – part of your stomach is removed but the intestines are not re-routed. Again, you won’t have to eat so much food to feel full.

“The procedure I had was a gastric bypass. Immediately after surgery, my consultant told me to stop taking metformin. 

“Within four months of having the surgery, my weight had dropped to 12 stone and my regular blood tests showed my blood sugar levels had returned to normal.

“I feel so much healthier and there is so much more I can do.”

Kieran had bariatric surgery – a gastric bypass – in August 2017. His type 2 diabetes is now in remission. Read Kieran’s story

When is surgery recommended?

Bariatric surgery is available on the NHS for people who meet certain criteria. These 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 

If you're considering surgery

Speak to your GP if you think bariatric surgery might be an option for you. If you qualify for NHS treatment, you will be referred for an assessment to check whether surgery is suitable.

The NHS guidelines are broadly similar to a set of international clinical guidelines published in 2016 by a group of leading international diabetes organisations, including Diabetes UK. These guidelines also recommend a lower BMI threshold for people from a South Asian background with type 2 diabetes. 

The risks of surgery

Any kind of surgery carries some risk with it. Bariatric surgery does not carry any greater risk than other common surgical procedures. You will have a thorough assessment before surgery is considered. And the risks will be explained to you. Following surgery, you will need long-term follow-up monitoring.

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.