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Gastric Sleeve vs GLP-1s: Which is Better?
This is entirely based on your personal preference and situation. Both methods are safe and effective for most people, but factors like cost, your feelings on surgery, and whether you want a permanent or temporary treatment could be deciding factors.
On this page we’ll explore their differences, as well as the pros and cons of each option.
Medically reviewed by
Alexandra Cristina Cowell, Writer & Clinical Content Reviewer
What is a gastric sleeve?
A gastric sleeve is a surgical procedure in which around 70-85% of your stomach is removed. It’s an effective procedure, with patients experiencing an average of 82% excess weight loss one year after surgery.
While gastric sleeve surgery does come with some risks, such as infection, bleeding, nutrient deficiencies, and excess skin, the benefits often outweigh these concerns, especially when compared with the serious health risks of untreated obesity, which include a greater risk of heart attack, stroke, type 2 diabetes, joint pain, and more.
It’s important to understand that, as with all weight-loss treatments, there’s a risk of weight regain even after a gastric sleeve. A systematic review found that around 5.7% of people regained weight by the two-year mark, and this percentage increased to 75.6% six years after the surgery. Although part of the stomach is removed to reduce its volume, it can still stretch over time, potentially leading to increased appetite.
Several other factors can contribute to weight gain, such as not sticking to your diet, mental health challenges, a lack of physical activity, and hormonal or metabolic imbalances. To reduce the risk of regaining weight, it’s crucial to adopt a healthy lifestyle after surgery. You should also have regular follow-up appointments with your clinician so they can check everything’s progressing well.
Who is a gastric sleeve best for?
To be considered for the gastric sleeve, you need to meet the following criteria:
- Have a BMI of 40 or more.
- Have tried losing weight through other ways first, including diet, exercise, and medicine.
- You’re willing to make healthy lifestyle changes after treatment.
Your doctor might recommend a gastric sleeve if you have a lower BMI (between 35 and 40) alongside a weight-related health condition, like type 2 diabetes. The requirement is also lower for people of South Asian, Chinese, other Asian, Middle Eastern, Black African, or African Caribbean background.
A gastric sleeve is usually a last resort treatment for weight loss. Your doctor will typically suggest you diet and exercise first. If that doesn’t work, they’ll recommend weight loss medicine like Orlistat, Semaglutide, or Tirzepatide.
What are weight loss injections?
Weight loss injections are weekly or daily self-injectable treatments to aid weight loss. There are a few options available, such as Mounjaro, Wegovy, Nevolat, and Saxenda. They are effective medicines that can help you lose over 20% of your body weight by week 72.[popoverid=ref4]
Although they all work similarly, by reducing hunger levels and decreasing appetite, there are a few key differences between them:
- Active ingredients. Wegovy contains semaglutide, Nevolat and Saxenda contain liraglutide, and Mounjaro contains tirzepatide, which is a dual GLP-1 (glucagon-like peptide-1) and GIP (glucose-dependent insulinotropic polypeptide) receptor agonist. This makes tirzepatide more effective than semaglutide and liraglutide.
- How often you inject them. Wegovy and Mounjaro are injected once weekly, while Nevolat and Saxenda are injected once daily, making them a bit less convenient.
- Price. Nevolat is the most affordable option and Mounjaro is the most expensive.
Like all medicines, there’s a risk of getting side effects when using them. The most common ones are gastrointestinal, such as nausea, vomiting, diarrhoea, or constipation. But they should only last for a short period of time, until your body adjusts to the treatment. Overall, it’s a less invasive and intensive method than a gastric sleeve.
Who are weight loss injections best for?
The requirements for getting a weight loss injection on the NHS are higher than if you were to get it privately.
Via the NHS, weight loss injections are prescribed for people with a BMI of 40+, or 35+ with a weight-related health condition like type 2 diabetes or high blood pressure. The requirements are also lower for people of South Asian, Chinese, other Asian, Middle Eastern, Black African, or African Caribbean background.
Via a private provider, however, you only need to have a BMI of 30+, or 27+ with a weight-related health condition.
Gastric sleeves vs Weight loss injections
Important considerations
It’s important to consider everything before coming to a decision, including:
Cost
Gastric sleeve
A gastric sleeve is free on the NHS, but there’s a waiting list of over a year. You’ll also have to meet extensive criteria before you can have the surgery, as it’s often a last resort treatment.
If you go private, the surgery can cost anywhere from £8000 to £15,000. The waiting time will be much shorter, sometimes even less than a week depending on the circumstance.
Weight loss injections
Weight loss injections cost £9.90 per prescription on the NHS. This includes a pen that lasts four weeks, so over a year the total cost is around £128. While this is significantly cheaper than private prescriptions, the NHS has stricter criteria for weight loss injections. There’s also a shortage of medicines and limited availability, so there may be a long waiting list.
Privately, a year’s supply of Mounjaro can cost around £5400 and a year’s supply of Wegovy can cost around £3500. While this is significantly more expensive, there’s often no waiting time and a lower eligibility criteria (you only need a BMI of 30+ or 27+ with a weight-related health condition as opposed to 40+ on the NHS).
Efficacy
Both methods are effective at helping you lose weight. People lose an average of 25% of their body weight within a year after gastric sleeve, while you can lose up to 20% of your body weight within 72 weeks (a little over a year) of using Tirzepatide.
To get the best from both treatments, it’s essential to make healthy lifestyle changes alongside them. Without proper maintenance, there’s a significant risk of regaining weight with either option. So it’s important to continue following a healthy diet and exercising regularly.
Safety
Both treatment methods are safe, but there’s a risk of getting side effects with each option. That said, the benefits of weight loss usually outweigh the potential risks and side effects of treatment.
Gastric sleeve
The surgery itself is very safe, with many patients having no complications. While there’s a slight risk of side effects, a study found that people who underwent gastric sleeve surgery had a reduced risk of mortality, complications, and reintervention.
Additional health benefits include reduced blood pressure, a lower risk of stroke, cancer, non-alcoholic fatty liver disease (NAFLD), cardiovascular disease, and much more. Type 2 diabetes may also be reversed.
Weight loss injections
Weight loss injections are generally safe and well-tolerated. Although nearly all users may experience gastrointestinal side effects, such as nausea, vomiting, and diarrhoea, these effects are usually manageable. In fact, only 1.8% of patients discontinued treatment with tirzepatide due to side effects. Furthermore, most side effects tend to subside within a few weeks as your body adjusts to the medication.
Other health benefits include reduced blood pressure, a lower risk of stroke, cancer, non-alcoholic fatty liver disease (NAFLD), cardiovascular disease, and improvement in blood sugar levels and knee and joint pain.
Which is the best option for you?
This choice largely depends on your personal preferences. If you’re looking for a permanent and convenient solution, a gastric sleeve might be the best option for you. But if you prefer a less invasive approach and are okay with regular injections, weight loss injections could be more suitable.
Regardless of either option, you’ll need to make lifestyle changes and maintain your progress through proper dieting and exercise.
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Five-year outcomes of laparoscopic sleeve gastrectomy as a primary procedure for morbid obesity: A prospective study. World Journal of Gastrointestinal Surgery, 9(4), 109.
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What is weight loss surgery?
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