Bariatric surgery: Everything you need to know

Find out more about bariatric surgery and whether it is right for you.
Habitual Team
min read
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Quick summary

According to a recent study, 37.9% of adults in the UK are overweight, and a further 25.9% are dealing with obesity. [1] As such, it is hardly surprising that many individuals are on the lookout for a healthy and sustainable way to lose weight.

While there are many avenues to pursue in this regard, such as following a calorie-controlled diet, increasing exercise levels or taking weight loss medication, each year, more and more people turn to surgical inventions, such as bariatric surgery.

What is bariatric surgery?

A few different forms of treatment that fall under the umbrella of bariatric surgery. This includes:

  • Gastric Bypass. A gastric bypass is a surgical treatment that reduces the size of the stomach by creating a small "pouch" from the stomach and connecting this to the small intestine.
  • Gastric Band. A gastric band is a keyhole surgical treatment that reduces the size of the stomach by wrapping a small band or tube around it.
  • Gastric Sleeve. A gastric sleeve is a surgical procedure during which around 80% of the stomach is removed. [2]
  • Gastric Balloon. A gastric balloon is a temporary form of weight loss treatment during which an inflatable medical device is placed inside the stomach.

By effectively shrinking the size of the stomach, individuals feel fuller for longer, reducing their appetite and food intake. This, in turn, is often associated with significant weight loss.

Does bariatric surgery work?

Many of those who have undergone bariatric surgery will notice positive results.

For example, one study found that patients who had undergone bariatric surgery exhibited 'rapid' weight loss in the first four months following the operation, losing, on average, 4.98 kg/mo. [3]

The majority of the weight loss will take place within the first six months to a year of the operation, and a weight loss of over 50% of excess weight is considered a success. [4]

Generally speaking, a proportion of those who have undergone bariatric surgery will regain some of the weight lost initially, especially over long periods of time. [5] However, the amount of weight regained is often relatively minor. For example, a recent study found that gastric bypass patients regained 3.% % of their body weight, and gastric sleeve participants regained 1.4% between three and seven years after the surgery. [6]

There are also many other benefits tied to bariatric surgery. One study found that five years after bariatric surgery [7]:

  • Only 14% dealt with the complications of type 2 diabetes (down from 36% pre-surgery)
  • 72% of patients were physically active (up from 34.4% pre-surgery)

Is bariatric surgery safe?

Most of those who undergo bariatric surgery will not encounter any major issues during the surgery and their recovery. However, as with any form of medical intervention, there are risks associated with this procedure. Common complications include [8]:

  • Blood clots
  • Stomach leak
  • Gastric band slipping out of place
  • Wound infection
  • Blocked gut

Bariatric surgery is also associated with an increased risk of malnutrition, especially when patients are not following a healthy, balanced diet following their treatment. For example, one study found that vitamin deficiencies, including vitamin D, A, and iron, are particularly common among post-op patients. [9]

Patients can work to minimise the chances of dealing with post-op complications by carefully following the recovery plan laid out by the team in charge of their care. This typically involves following a specific diet and exercising.

What is the criteria for bariatric surgery?

To be eligible for bariatric surgery, you need to meet specific criteria [10]:

  • A BMI (Body Mass Index) of over 40.
  • A BMI of over 40 and dealing with a health condition that could be minimised through weight loss, such as type 2 diabetes, high blood pressure, or arthritis.
  • Have tried other, more traditional weight loss methods first, such as exercising and dieting without success.

Individuals being considered for bariatric surgery must also agree to make an effort to follow a healthy lifestyle following the surgery. This can reduce complications and further weight gain.

How does surgery work in the UK?

Bariatric surgery is available in the UK through the NHS and private healthcare providers. Understanding your options ahead of time means you can make the best possible decision regarding your health and well-being.


What kinds of bariatric surgeries are available on the NHS?

Numerous forms of bariatric surgery are available on the NHS. This includes:

  • Gastric Bypass
  • Gastric Sleeve
  • Gastric Band
  • Gastric Balloon

The type of procedure offered to patients can vary depending on a variety of factors, such as your current weight/BMI, lifestyle and any pre-existing healthcare conditons you may be facing.

Do I qualify for bariatric surgery NHS?

In order to qualify for bariatric surgery under the NHS, you'll need to meet the criteria listed above. You'll also need to attend numerous appointments with different specialists ahead of time, who will determine whether or not you are a suitable candidate for bariatric surgery.

What is the wait time for bariatric surgery on the NHS?

The wait time for bariatric surgery on the NHS can vary on a case-by-case basis. However, the referral process can often take several months due to the fact that the surgeries are so in-demand.

NHS bariatric surgery timeline.

General appointment. 

Those interested in seeking bariatric surgery on the NHS should contact their GP. They will be able to determine whether or not you are eligible for this treatment method or whether alternative routes could be considered. For example, this could include weight loss aids such as Wegovy or Mounjaro.

If the GP feels you are a candidate for bariatric surgery based on the criteria outlined above, they will refer you to a local team or facility.

Initial referral. 

During the initial referral, the clinician in charge of your care will conduct a number of basic health screenings, such as taking your blood pressure and weight. They will also discuss your eating habits or any previous diets you may have followed. This ensures that bariatric surgery is the best course of action based on your lifestyle, mental well-being and medical history.

After your consultation, they'll arrange for numerous tests to take place to ensure that it is safe to proceed with bariatric surgery. This could include blood and urine tests, sleep studies and ECGs.

Second appointment. 

Once the results from the studies have been gathered, you'll be invited to attend a second appointment. Here, it will be determined whether or not you are a viable candidate for surgery. You will then be referred to a surgical team.


It is generally advised that you attempt to lose weight naturally ahead of your surgery date, and in some cases, it may be deemed medically necessary. Your doctor may also put you on a liver shrinkage diet ahead of your surgery, which can help to simplify the surgical procedure itself. [11]


Most patients can leave the hospital within 1-3 days of their surgery, ensuring they are not experiencing any complications. However, the total recovery period is between 4-6 weeks. Following surgery, you'll need to follow a very specific diet, which is liquid-based for the first two weeks. A specialist exercise plan will also be put in place, which can help to avoid complications and ease your transition back to your normal routine. You'll also have to attend regular follow-up appointments.

Private Options.

There are many reasons why you may want to pay privately for your bariatric surgery. After all, this means you can access the same high level of care and support without the long wait time typically associated with the NHS.

How much does bariatric surgery cost?

The cost of bariatric surgery can vary depending on various factors, such as the private facility you've selected or the nature of the procedure. Generally speaking, prices start from around £10,000.

Medical Tourism.

In recent years, a growing number of individuals have travelled abroad to undergo bariatric surgery to avoid long waitlists or the costs of going private. However, this may not be the best course of action.

This form of treatment in the UK is highly regulated, which helps keep patients safe. Abroad, the same guarantees are not always made, even if the surgeon comes highly recommended. They may also be less stringent in who they allow to participate in this form of treatment.

If you are considering participating in medical tourism, it's often advised to speak to your doctor beforehand. You should also research the surgeon and facility as much as possible so that you can make a more informed decision.

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How Does Bariatric Surgery Compare To Other Weight Loss Medications?

Bariatric surgery is not the only way to facilitate healthy weight loss, even among those who struggle to lose weight following more traditional routes. For example, many people have achieved great results when using weight loss medications, such as Mounjaro and Wegovy, especially when making lifestyle modifications alongside this.

What are Mounjaro and Wegovy?

Mounjaro. Mounjaro is a weight loss aid used in treating both obesity and type 2 diabetes. Administered through a weekly injection, participants lose, on average, 20.9% of their body weight in 72 weeks on Mounjaro.

Wegovy. Wegovy is a medication that was specifically designed to facilitate healthy weight loss. It is also administered through a weekly injection, and people lose 14.9% of their body weight in 86 weeks on Wegovy.

While they are made of different ingredients, both drugs work as appetite suppressants by increasing feelings of fullness among users. This means that it's easier to remain in a calorie deficit, and facilitate weight healthy weight loss.

How do they compare to bariatric surgery?

Both bariatric surgery and weight loss medication are viable options for those looking to lose weight, whether they pursue private healthcare and prescriptions or go through the NHS.

However, both Mounjaro and Wegovy are excellent choices for those who would like to avoid surgery. While they are administered through weekly injections, they are far less invasive than going down the surgical route.

As such, while it can take a little longer to lose weight through medication over surgery, it is the preferred option among those looking for a noninvasive yet still effective weight loss aid. 

If you’d like to find out more about either of these medications, or similar products such as Ozempic, please do not hesitate to get in touch today. 

Final Thoughts.

Struggling to lose weight can have a profound effect on an individual's overall health and well-being. For example, individuals who are classified as obese are more likely to deal with type 2 diabetes, sleep apnea, hypertension, and cardiovascular disease. [12]

While there are many possible avenues to explore for sustainable weight loss, bariatric surgery is one of the most effective, particularly among those who are classified as obese. Not only does it make it much easier for the patient to lose weight, but it can also bring forth positive changes relating to their health. For example, one study found that 'bariatric surgery reduced the risk of developing diabetes by 96% at 2 years post-intervention and 78% at 15 years.' [13]

When considering bariatric surgery, there are three potential paths: the NHS, private practitioners, or travelling abroad. Though many different factors can influence your final decision, from wait times to pricing, it is generally advised that you focus on care offered within the UK.

If you are interested in bariatric surgery, reach out to your GP or a local weight loss clinic. They will be able to provide you with tailored advice and guidance when it comes to losing weight or determining the best course of action moving forward.


[1] Adult obesity in England. UK Parliament. Retrieved 19 June 2024. Accessible here

[2] How weight loss surgery is done. NHS. Retrieved 19 June 2024. Accessible here.

[3] Douglas, Ian J., Bhaskaran, Krishnan., Rachel, L., et al. (2015) Bariatric Surgery in the United Kingdom: A Cohort Study of Weight Loss and Clinical Outcomes in Routine Clinical Care. PLOS Medicine. 12(12). Accessible here.

[4] Bariatric Surgery Frequently Asked Questions. NHS. Retrieved 25 June 2024. Accessible here.

[5] Noria, S. F., Shelby, R. D., Atkins, K. D., et al. (2023) Weight Regain After Bariatric Surgery: Scope of the Problem, Causes, Prevention, and Treatment. Current diabetes report 23(3)P31–42. Accessible here.

[6] Long-term Study of Bariatric Surgery for Obesity: LABS. NIH. Retrieved 20 June 2024. Accessible here.

[7] Nedeljkovic-Arsenovic, O., Banovic, M., Radenkovic, D., et al. (2020). Five-Year Outcomes in Bariatric Surgery Patients. Medicina (Kaunas, Lithuania) 56(12)P: 669. Accessible here

[8] Complications of weight loss surgery. NHS. Retrieved 19 June 2024. Accessible here.

[9] Ganipisetti, VM., Naha S. Bariatric Surgery Malnutrition Complications. (2023) StatPearls Internet. Accessible here

[10]Why weight loss surgery is done. NHS. Retrieved 24 June 2024. Accessible here

[11] Liver shrinkage diet for Bariatric Surgery. NHS. Retrieved 24 June 2024. Accessible here.

[12] Aronne, Louis J. (2002) Classification of Obesity and Assessment of Obesity-Related Health Risks. Obesity Research 10(12)P:105S-115S. Accessible here

[13] Affinati, A. H., Esfandiari, N. H., Oral, E.A., et al. (2019). Bariatric Surgery in the Treatment of Type 2 Diabetes. Current diabetes reports 19(12)P:156. Accessible here.

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