A gastric sleeve often suits you if…
you mainly want smaller portions, and you don't have bad heartburn.

Gastric sleeve or gastric bypass
Both help you lose a lot of weight and keep it off. Here's how they differ, side by side, in plain words.
How does it help you eat less? | |
|---|---|
About 80% of the stomach, including the part that makes the hunger hormone, is removed, leaving a narrow tube so you feel hungry less often. | A small pouch at the top of the stomach joins further down the gut, so a small meal satisfies you. |
How much weight do people usually lose? | |
About 60 to 70% of their extra weight, with around 6 to 7 stone expected in the first 12 months. | About 70 to 80% of their extra weight, a little more over the long term than a sleeve. |
What is the operation like? | |
Much the same for both: keyhole surgery through small cuts, 1 to 2 hours under general anaesthetic, usually one night in hospital and about two weeks to recover. | |
What if I have bad heartburn? | |
New or worse heartburn (reflux) can happen in some people, so a sleeve usually suits people who don't already have bad heartburn. | A bypass can work better if you already have bad heartburn. |
What about type 2 diabetes? | |
As the weight comes off, type 2 diabetes and blood pressure often ease. | Type 2 diabetes often improves very quickly, and for some people it goes into remission. |
Will I need vitamins? | |
Yes, but the risk of running short over the years is lower. | Yes, every day for life, with regular blood tests to keep an eye on your levels. |
What happens if I eat sugary food? | |
A sleeve doesn't cause dumping syndrome. | Sugary food can cause faintness or sickness called dumping syndrome, which your dietitian shows you how to avoid. |
Can it be undone? | |
No, the part of the stomach that's removed can't be put back. | Rarely, and only for medical reasons. |
If you've tried diets, apps or weight loss medication and the weight came back, either operation can help it stay off.
you mainly want smaller portions, and you don't have bad heartburn.
you have type 2 diabetes or bad heartburn.
You don't have to work this out alone. At your free assessment, your surgeon looks at your weight, your health and how you eat, and recommends the one that suits you.
Request my free assessment
Dr John Loy, head of our bariatric unit, performs both operations and has done almost 3,000 weight loss procedures. Your dietitian, the app, your follow-ups and a 24/7 number for the surgical team are all here in Ireland.
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A member of our team calls you back, usually within one working day, to answer your questions. If you'd like, we then arrange your free assessment, online or in person. No obligation.
We'll call you back, usually within one working day, to talk through sleeve and bypass with you. There's nothing else you need to do.
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“Meeting Dr Loy to discuss the best surgery for me, I felt it was the first time in my life I was genuinely being listened to and not just blamed or judged for being overweight.”
“I had done alot of research into my options beforehand & now that i'm through it I'm very happy with my decision to go with Auralia for my gastric sleeve surgery.”
Yes, a bypass can be done after a sleeve if you need more help later. Your surgeon can explain when that might make sense.
Each one has a single price that covers your assessment, operation, night in hospital and aftercare, and you can pay monthly over up to 36 months. Our team gives you your personal quote.
That's fine. The call is there to answer your questions, and nothing is booked unless you want it.
Get honest answers, then choose in your own time.