Gastric bypass surgery

We offer the latest surgical techniques to help you lose weight when diet and exercise haven't worked and your health is at risk because of severe obesity.

Sometimes also called

  • Roux-en-Y bypass

At a glance

  • Typical hospital stay
    2-5 nights

  • Procedure duration
    1-3 hours

  • Type of anaesthetic

  • Available to self-pay?

  • Covered by health insurance?
    Some insurers, by exception

Why Spire?

  • Fast access to treatment when you need it
  • Consultants who are experts in their field
  • Flexible payment options to help you spread the cost
  • 98% of our patients are likely to recommend us to their family and friends

What is gastric bypass surgery?

A gastric bypass, also known as a Roux-en-Y, is an operation your doctor may suggest if your health is at risk due to severe obesity.

The procedure involves reducing your stomach size and connecting it to the lower part of your small intestine.

This restricts the amount of food you can eat and the amount of calories you’re able to absorb through your small intestines. It also causes hormonal changes that deter you from eating unhealthy foods.

The benefits of gastric bypass surgery are:

  • Weight loss – on average people lose between 66% and 75% of excess weight in the two years after gastric bypass surgery
  • Improvements in any weight-related conditions you may have, such as type 2 diabetes, high blood pressure, high cholesterol and heart disease
  • You're more able to do physical activity which can lead to increased energy, fitness, strength, stamina, bone density, improved mood and self-confidence

Your doctor may recommend gastric bypass surgery if:

  • You have a BMI of 40 or higher - this is known as ‘morbid obesity’
  • You have a BMI between 35 and 40 together with a serious condition that could be improved with weight loss
  • You’ve tried to lose weight through diet and lifestyle
  • You’re willing to have long-term follow-up appointments and adopt a healthy diet and lifestyle
  • You’re medically fit for surgery

Your doctor may recommend gastric sleeve surgery first. This is an operation to reduce the size of your stomach without changing how your digestion works.

Find your nearest Spire hospital

Almost all our hospitals offer gastric bypass surgery and have teams of bariatric (weight loss) consultants and surgeons who specialise in this procedure.

Spire Nottingham Hospital

How gastric bypass surgery works

Your surgeon uses surgical staples to make a small pouch at the top of your stomach and connects it to the lower part of your small intestine. This means the food that you eat will bypass the rest of your stomach and the upper part of your small intestine, going straight into your lower small intestine.

This helps you lose weight in three ways:

  • Restriction - you won’t be able to eat as much as before because there won’t be room in your new, smaller stomach pouch
  • Malabsorption - you’ll absorb fewer calories because your food will come into contact with less of your small intestine
  • Deterrent – you won’t feel like eating a lot of sugar because if you do, your body will produce too much insulin, making you feel light-headed and sick. This is called ‘dumping syndrome’

"The whole point of this surgery was to just live a normal life"

Colin, Imogen and Mary

Three bariatrics patients who underwent weight loss surgery at Spire Gatwick Park Hospital

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♪ [music] ♪- [Man] What a journey it's been. Sixteen months ago I had gastric bypass and I've lost eight stone. It's a journey that I didn't undertake lightly.

It's something I had to consider for a long period of time. - [Woman 1] It's a big decision.

- Huge decision. - [Woman 2] Life changing.

- Yeah. Well, for me it was a no-brainer. I mean, you could just spend the rest of your life being miserable or have this operation that is surprisingly easy, actually. I mean I don't know about you guys but I always thought it was this massive operation and you'd never be able to eat again. And it would be so...

- No, it really was quite easy, really.

- and actually it's so little, isn't it?

- Yes, absolutely.

- It doesn't really affect your life that dramatically in any negative way, I don't think.

- Well, mine was about four years ago now and I lost eight stone. I regained one, which is okay, but I absolutely love it. Doesn't stop me doing anything. In fact, it means I can do things I couldn't do before.

- Yeah, it does the opposite, doesn't it?

- So I can't say I wish I'd had it sooner because it was the right time to have it then, but absolutely no regrets and I would do it again tomorrow.

- I considered the op too long. I'd been thinking about it when I was 20, 25, 30 and my biggest regret is not doing it sooner. You know, why did I wait until I was 46 to have the operation done?

- We're quite opposite. I mean, I literally researched it and then three days later booked in.

- Some people said to me, you know, "You're being selfish having a surgery. You should just go on a diet." If just going on a diet was that easy... I've been on 30, 40 diets.

- But we've all dieted. We've been there. We've lost the weight, put it on plus more and that's just the way it goes, isn't it?

- And the knock-on effect of that constant dieting just puts you into this spiral of constantly thinking, you know, why can't I just get to a normal weight? Why can't I just be normal?

- Yeah.

- And that's one thing I think we all had in common is we just wanted to be normal.

- Normal.

- Yes.

- And for some people, it's normal again. For me, I've never been normal. I've always been big since I was nine years old.

- Yeah, and when you think about how hard it is to be overweight, it's just not worth spending a second being that way.

- No.

- If you've got a choice and you can do it, it's just the difference is...I don't know about you guys but it is a different life the way people treat you, the way you feel, what you can do. Just the way you think. Like I think so differently.

- There is a stigma with being big. Whatever people say, people do...

- It's horrific.

- Yeah.

- I've been abused in the street for being overweight. I would never eat anything in a public street, in a street where people could see me. I could never walk into a baker's and get a sausage roll because I'd be vilified for standing outside eating it. "Why are you eating that, fatty?"

- Well, I would eat my lunch in the toilet. You know? - [crosstalk] or you don't eat your lunch at all.

- I literally spent three years eating my lunch in the toilet because I was so ashamed of people seeing me eating.

- That's right.

- And it's horrendous. That's a hideous thing to have to do.

- It is.

- It's these things but as soon as you lose that weight, you get this freedom. Like, "I can eat that and not be ashamed."

- That's right.

- And it gives you confidence, as well because you know you look all right and you just fit in now.

- Yeah, just normal.

- You're just normal.

- Yeah, you can buy treats in any shop you like.

- But also feeling comfortable again because I've never, ever felt comfortable in any kind of clothes, whether it be jeans or tops. Everything's too tight. It'll stick to you. Especially in the summer, you'd feel uncomfortable and, you know...

- That sense of discomfort is horrible.

- Yeah.

- I sometimes look at thin people now and think, "Oh, you don't know how easy you've got it and how easy everything is." Because being big, you know how difficult it can be and how it's just so much easier, like walking. Like you were saying you walk a lot because you don't have to think about it anymore. It's not [crosstalk]

- Before, I would shy away from anything physical, you know, because I'd get hot and sweaty, my knees were killing me. I wouldn't walk half a mile. I wouldn't even walk to the local shop.

- You took a car everywhere?

- I would drive everywhere.

- It's just so difficult, isn't it? It's so hard.

- You don't want to walk because fear of being in pain, fear of being stared at, and the worry of just going out sometimes.

- don't know about you guys...obviously, I had a different operation to you but within 24 hours I was normal. I had a little bit of sickness, if that. It was nothing and then I was back to normal.

- So how many nights did you stay in after your op?

- I stayed in two.

- Two, yes.

- But I think that's more precautionary. I was literally fine by midday, the day after. I was completely normal. It was incredible, actually. It was nothing. Literally nothing. I remember I went back to work because I'd told them that I had been on holiday, and I went back in...bear in mind, it was seven days afterwards and they said, "Oh, you look really well and you look really tan."

I was like, "Oh, thank you." Little did they know that I'd had an operation but that's how easy it was. It was absolutely fine.

- Yeah.

- How did you find it?

- I found it quite easy. I've got a big dog and I wasn't allowed to walk him because of stitching, I think. So I had to have somebody who came and walked the dog for me for about the first three to four weeks that I felt a bit weak. So I wanted to go out with him but I couldn't. But anyway, once I got him back, everything was fine and, yeah, I found it pretty easy, really.

- Yeah, I didn't find it so easy.

- No?

- No, I felt like I'd been hit by a bus.

- What about fat or excess skin? Have you got much of that left?

- I do. Yeah, I cannot wait for the day I have my tummy tuck. I've been going on about it, haven't I, probably since the day after I had the surgery.

- So you knew straight away you were going to have that done?

- Yeah, definitely because I'm 25. You know, I want it to look better. So I still have probably a couple of stone that I want to get rid of and then I'll be good, but I cannot wait. To me, like, you get a lot of people who say, "Oh, you know, it's loose skin. I don't want loose skin." And they worry about it but actually, it just is the smallest inconvenience. I don't know about you guys, but compared to the weight, the skin, it just doesn't matter.

It doesn't matter at all.

- I can live with it because you can cover it up.

- You can cover it up and if it comes up as an issue, it's not something that's not fixable. If you do some toning exercises you can make it better.

- Yes, yes.

- It's not something that I think should be a consideration because what you get from the surgery is definitely worth a bit of skin.

- Absolutely.

- It doesn't matter at all. It's not something that ever bothered me.

- You have to change your mindset. The mindset is what has to change first before you have the surgery. You have to be prepared to make some changes and big changes.

- Yes, which is why it's not necessarily the right thing for everybody because some people wouldn't be prepared to do that and so it wouldn't fix it for them.

- No, you've got to be willing to put in the work.

- Absolutely.

- I mean, it is the support, isn't it, that's the most important thing. I'm really quite lucky because we've got the psychotherapist, we've got the dietitian, the specialist nurse. So we sort of were aware going into it what it was going to be, how much work it's going to take. We've also got that support because we know what to do and they're always there, aren't they?

- It's great that we can talk to each other, as well, in that Facebook chat. So if somebody's got an issue, they can say something and the surgeon usually gets back in minutes. He keeps up with it as much as he does, but we can get the proper advice from people who know.

- Yeah, we are lucky. It's really important to get that program where you've got that support and you've got that contact and those people advising you because personally, for me, the group thing was actually the most important bit. Because being part of a group like we were, the support group, that was the reason a lot of the time that I want to do so well. You know, I've got friends and they're there and they're there supporting you and you want to do well for them.

And, you know, you don't want to disappoint them. Now you want to do it together...

- And they understand.

- ...and do a good job. And they understand.

- Because they've been there.

- Yeah. It's really important to have that group dynamic. We're in it together and this's what you need. Otherwise, you [inaudible] lack that bit of information. It's that bit of reason to get up and go.

- And it's set up so that's for life, isn't it? You've got the option of going to those meetings that are on a monthly basis forever, which is a wonderful thought.

- Knowing that that support's in the background is one of the reasons that I had my surgery at Spire.

- It's also the fact that we can go back, as well, if we were to have any problems. You can go back and see your dietician, see the psychotherapists. They are always there for whatever stage you're at, however you're feeling. We've got that. You know, it's important.

- It is important.

- And that first six months post-op, I think are the most significant part of the healing process.

- Yes, because we're still learning, aren't we?

- Yes, we're learning how to eat, how to refocus the mindset around food. I learnt some important lessons over that first six months, that it doesn't have to be uncomfortable or painful or as dramatic. You can eat and live a fairly normal life, just on smaller quantities. Be careful of what you eat. I never, ever thought I was on a diet after the surgery.

This was never about dieting ever again. I never want to be on a diet. The whole point of this surgery was to just live a normal life, eat how normal people eat, and become normal. And I've achieved my goal. I can eat a sandwich. I can eat a small bowl of pasta.

I can eat a small dessert. Everything is just in small portions.

- Yes, moderation.

- Moderation and...

- Knowing when to stop.

- Which is how I should have been eating before I put eight stone on and I think once you've got your head round that and you're focused on making a definite change in your life, then you can see the benefits of it. And this is the first time in my entire life I've been a normal weight.

- Yes, ditto. A wonderful feeling, isn't it?

- It's crazy. It's absolutely crazy. I still look in the mirror and I don't recognise myself. I look in my wardrobe and I'm like, "Look at all these clothes."

- For me it's pictures.

- And pictures, yeah.

- You look at pictures and you think, "Who on Earth is that? That's not me. I can't look like that." It's crazy but...

- But it's not about how we look. It's about how we are inside. It's got to be healthier for us and the older you get, the more important it is because you can't carry on being the weight that I was before without something going wrong. Whether it would have been joint issues or heart or turning diabetic. Something would have gone wrong if I hadn't addressed it like this.

- And I'm looking forward to my new life.

- Absolutely.

- My new life as a [inaudible]

- You should actually look forward to it.

- As a normal person.

- And it must have prolonged your life.

- Hundred per cent. It's got to have done.

- They say eight years, on average, [inaudible]

- I saw my GP about six months ago and he said, "You know what?You having this bypass and losing the weight, you probably saved the NHS £50 grand over the next 20 years by not having to go on diabetic medication.By not having to have the knee surgery." Because that was called off because my knees have improved.

So I can only see positives that I hadn't thought of being negatives about the surgery. But obviously pre-op, yes, I had fears like everybody else, but they went away.

- We're a very lucky bunch.

- We certainly are. ♪ [music] ♪

Your operation: what to expect

Before surgery

You’ll be assessed to check that you’re fit for the operation. This may include blood tests, X-rays and scans, as well as an explanation of the surgery and long-term outlook.

You may need to follow a calorie-controlled diet to reduce the size of your liver. This will make the operation easier and safer.

During the surgery

A gastric bypass is a major operation so it’s carried out under a general anaesthetic, meaning you’ll be asleep.

It’s usually done by laparoscopic (keyhole) surgery, though this method isn’t suitable for everyone. Keyhole surgery has a much faster recovery time than traditional open surgery.

During the operation, your surgeon will:

  • Make small incisions (cuts) in your abdomen and pass through a tiny camera and instruments
  • Use surgical staples to make a pouch, about the size of a walnut, at the top of your stomach
  • Cut your small intestine and attach the lower part of it directly on to your new pouch
  • Join the remainder of your stomach and upper small intestine to the lower part – so digestive juices from your stomach can drain out
  • Close your incisions

If your surgeon thinks keyhole surgery isn’t suitable for you, they may suggest open surgery, which involves making one single, much larger cut.

How long does a gastric bypass operation take?

Between one and three hours.

Pain after gastric bypass surgery

It’s normal to feel some pain and discomfort after gastric bypass surgery, though it’s different for everyone. You’ll be given pain relief to help you.

Your hospital stay

You’ll usually be in hospital between two and five nights.

Q & A

Simon Monkhouse, Consultant Upper GI and Bariatric Surgeon

Talking about gastric bypass surgery

Your recovery: what to expect

Recovery time

You should be back to your normal activities by six weeks but may experience changes as your body reacts to rapid weight loss in the first few months. This includes symptoms such as aches, tiredness, dry skin, feeling cold, thinning hair and mood changes.

Aftercare and ongoing treatment

Your recovery care will include:

  • Pain relief
  • A review of any medicines you’re taking for weight-related conditions, such as diabetes or high blood pressure
  • A carefully controlled diet plan for the first four to six weeks, moving from liquids to pureed, soft then solid foods, plus advice on eating and portion sizes
  • An exercise plan to help speed your weight loss and improve your fitness
  • Blood tests to check if you need extra vitamin and mineral supplements

Your lifestyle after treatment

The surgery won’t stop you craving or eating unhealthy food, so you must be willing to make long-term lifestyle changes.

You’ll need to attend follow-up appointments for the rest of your life. Eventually, these may just be annual checks to make sure your bypass is working properly.

You should avoid becoming pregnant during the first 12 to 18 months after surgery. Your nutritional levels are likely to be low during this time, which could harm your baby.

Risks and complications

Most people have gastric bypass surgery without complications, but all surgery carries some risks. Your consultant will explain them to you before you go ahead.

Although rare, gastric bypass complications can include:

  • Blood clots
  • Infection
  • Food leaking from the join between your stomach and small intestine, or the gut becoming blocked or narrowed
  • Nutritional deficiencies
  • Gallstones
  • Folds of skin due to rapid weight loss – further surgery can remove them

At Spire hospitals, your safety is our top priority. We have high standards of quality control, equipment and cleanliness and an ongoing system of review and training for our medical teams.

Treatment and recovery timeline

Although everyone’s different, here’s a typical recovery timeline for gastric bypass surgery:

View interactive timeline View full timeline

2-5 days

Able to leave hospital

4-6 weeks

Follow a controlled, monitored diet

4-6 weeks

Back to most activities and some weight loss

3-6 months

Less symptoms of rapid weight loss

2 years

Most weight loss will have happened

  • 2-5 days

    Able to leave hospital

  • 4-6 weeks

    Follow a controlled, monitored diet

  • 4-6 weeks

    Back to most activities and some weight loss

  • 3-6 months

    Less symptoms of rapid weight loss

  • 2 years

    Most weight loss will have happened

The treatment described on this page may be adapted to meet your individual needs, so it's important to follow your healthcare professional's advice and raise any questions that you may have with them.

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