Weight Loss Operation
Types of Weight Loss Operations

Dietitian, Juliette Kellow explains the types of operations available for weight loss in the UK.

Types of Weight Loss Operation Available in the UK

By Dietitian, Juliette Kellow BSc RD

Operations for obesity are not a miracle cure to help people shift a few unwanted pounds and should not be considered to be similar to cosmetic surgery. They are a last resort for people who have severe health problems due to their excessive weight.

All surgery comes with risks and these risks are even greater for people who are obese, so any procedure should be given plenty of thought and not be undertaken lightly.

Before undergoing surgery you should be properly prepared and understand both the risks and the benefits, both in the short and long term.

You should also be fully aware of what you can expect to achieve and the type of lifestyle changes you will need to follow after the operation, including changes to your diet.

The type of operation you have will help to determine how much weight you will lose. But a big part of the success of any of the treatments will depend upon your willingness to change your eating and lifestyle habits.

Don’t be fooled into thinking that having a weight loss operation means you won’t ever need to diet or exercise again.

Ultimately, for most people, surgery means they will be on a life-long restricted eating plan that allows only small amounts of food.

Bottom line: large meals, loads of snacks and lots of fatty and sugary foods will continue to be off the menu.

There are several operations for weight loss to choose from and obese people who are suitable for surgery should discuss the risks and benefits of each with a health professional.

Some weight loss operations reduce the size of the stomach so that only small amounts of food can be eaten; others bypass part of the small intestine so that the body absorbs fewer calories from food; and others combine the two.

Types of Weight Loss Operation available in the UK

Implantable Gastric Stimulator

This operation is not readily available on the NHS.

The procedure involves implanting two electrodes into the wall of the stomach via keyhole surgery. These are then attached to a small battery powered stimulator that’s inserted beneath the skin to the side of the stomach.

The stimulator sends out programmed electrical pulses to the electrodes, which in turn stimulate the stomach to send messages to the brain to induce feelings of fullness.

Initial trials revealed that 80 percent of people lost weight after having the device implanted, with 60 percent losing more than 10 percent of their body weight over 29 months.

Bilopancreatic Diversion

The Bilopancreatic Diversion removes about 75 percent of the stomach and attaches the small pouch that remains to the final part of the small intestine. Bile and pancreatic juices that aid digestion are also diverted to enter the small intestine lower down.

This type of operation works by enabling most of the fat and carbohydrate eaten to pass through the body without being absorbed.

Unfortunately, side effects include loose stools and foul-smelling flatulence. Plus ulcers can develop at the junction of the stomach and small intestine. The surgery can be carried out by keyhole or regular surgery.

Gastric Bypass

Like the gastric band, this procedure tends to be carried out using keyhole surgery but involves 4-5 nights in hospital. It can also be carried out by normal surgery for people who are very obese where keyhole surgery may not be suitable.

This operation has more risks and complications attached to it than a gastric band. Plus complications can happen after surgery, for example, developing a leak from the join between the stomach and the small intestine, development of a hernia or nutrient deficiencies due to the poor absorption of nutrients.

Weight loss is normally greater than with a gastric band – studies show that on average, people lose between 66 and 75 percent of their excess weight.

As with a gastric band operation, you will need to dramatically change your diet, starting with fluids only for the first week, then progressing to puréed food for the next three weeks and mashed food for the next two weeks. You will also need to take vitamin and mineral supplements for life as the surgery affects the absorption of these nutrients.

Duodenal Switch

This is a variation of the bilopancreatic diversion. A large portion of the stomach is removed by a sleeve gastrectomy.

At the base of the stomach, a small section of the small intestine (the duodenum) is left behind, but the remainder is cut. The lower half of the small intestine is then joined to this small piece of remaining duodenum. As with the bilopancreatic diversion, bile and pancreatic juices are redirected to the lower part of the small intestine.

The operation can be performed by keyhole or regular surgery but it’s extremely complex and can take up to seven hours to complete, and requires 5-6 days in hospital.

This operation is linked with the greatest weight losses – after two years, 80 percent of people reach a normal weight – but it’s also one of the most risky operations.

It also has unpleasant side effects including wind and diarrhoea caused by the malabsorption of fat, although eating a low-fat diet can help to limit this.

Nutrient deficiencies, including protein, iron, zinc, and the fat-soluble vitamins A, D, E and K, are also more likely and can lead to severe malnutrition. Supplements therefore need to be taken for the rest of life, together with a diet that contains twice as much protein as normal.

Gastric Band

A gastric band acts like a belt around the top part of the stomach and creates a small pouch. Food enters the pouch and then passes slowly through the opening created by the band into the main part of the stomach.

Ultimately, a gastric band severely restricts the amount of food that you can comfortably eat and helps to keep you fuller for longer.

It’s fitted using keyhole surgery in a one-hour operation under a general anaesthetic. Most people are in hospital for no more than 1-2 days.

The band can be tightened or loosened to alter the amount of food that can be eaten and the rate at which it passes into the main part of the stomach – in fact, most people have their band adjusted several times in the early months until the setting is optimal for their individual weight loss. These adjustments take only a few minutes and don’t require an anaesthetic.

Whilst a gastric band is usually fitted with plans to leave it there permanently, one of the main advantages is that it can be removed without leaving any permanent changes to your stomach.

Studies show that people lose between 50 to 65 percent of their excess weight within two years of having a gastric band fitted.

However, you still need to be prepared to restrict what you eat. Ultimately, this involves pureeing all your food for around the first four weeks, followed by mashing for the next few weeks, before finally returning to solid food – and even then, you will only be able to eat small amounts.

Complications are rare with this procedure.

Intragastric Balloon

The Intragastric Balloon operation isn’t readily available on the NHS but more research is being carried out on it and it’s sometimes an option for private patients.

This is a short-term treatment that involves placing a deflated silicone balloon into the stomach through the mouth and gullet under sedation. Once in the stomach, the balloon is filled with liquid and so partially fills the stomach to create a feeling of fullness.

The balloon must be removed after six months – if it’s not removed it can deflate and cause an obstruction.

This type of operation is considered to be most appropriate to help people lose weight before they have any type of surgery.

It’s also a good option for people for whom surgical procedures to treat obesity may be inappropriate.

So far, studies have shown a weight loss of between 25 to 44 percent of their excess weight after having an intragastric balloon fitted.

Sleeve Gastrectomy

This operation reduces the size of the stomach by around 75 percent. The stomach is divided vertically from top to bottom, leaving a banana shaped stomach along the inside curve.

The stomach still functions as normal, but is much smaller so that people who have this operation can only eat small meals.

The operation is usually done by keyhole surgery and requires a 1-2 night stay in hospital. Most people lose 30-50 percent of their excess weight in the first 12 months.

This operation is sometimes carried out as the first step in a two-part procedure for extremely obese people with a BMI of 60 or more, where other procedures are more risky to them. After 12 to 18 months of receiving a sleeve gastrectomy, these people may then go on to have a gastric bypass or duodenal switch.

Stomach Stapling (Vertical banded gastroplasty)

This operation is now considered to be obsolete by most surgeons and has been replaced by the gastric band, which has fewer side effects and a more positive outcome.

Summing Up

As you can see, having operation to lose weight is a complex subject that will need a lot of consideration and preparation. If you are thinking that it may be an appropriate treatment for you, make an appointment with your GP who will be able to talk to you about eligibility, benefits and risks and other options.

You can find more information about having surgery in my Weight Loss Surgery Q & A

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For more information on surgery to lose weight see Weight Loss Surgery Info.

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