'Is weight loss surgery right for me?'

If you’re very obese and you’ve already tried improving your diet and exercise levels without success, then weight loss surgery could be the right option for you. But it’s not a short cut to losing weight easily as it will mean changing the way you eat forever.

If you are overweight, the best way to lose weight is by making long-lasting changes to your diet and level of physical activity. You can learn how by reading more articles in Lose weight.

But in cases where lifestyle changes, accompanied by weight loss medicines when appropriate, are not enough, then weight loss surgery, also called bariatric surgery, may be an option.

When considering weight loss surgery, it’s important to bear the following in mind:

  • Weight loss surgery should be seen as a last resort.
  • Not everyone is eligible to have it done on the NHS.
  • After surgery, you will never be able to eat the same way again, or you will become very ill if you do.
  • After surgery, you will need to follow a carefully controlled diet and take regular exercise.

You’ll need to show that you’ve changed your diet and lifestyle before the operation, and you'll have to stick to long-term changes afterwards. But surgery can help very overweight people to lose significant excess weight.

If you’re interested in weight loss surgery, talk to your GP to learn more.

What is weight loss surgery?

There are two main kinds of weight loss surgery.

  • Gastric banding. Here, a band is fitted around the top of the stomach. This causes a feeling of fullness after eating a very small amount of food, and means that food must be eaten very slowly.
  • Gastric bypass. Here, a much smaller stomach is made. This causes a feeling of fullness after eating a small amount of food, and means that the body absorbs fewer calories.

Both procedures are designed to be permanent. Learn more about these and less common weight loss operations.

Who can have weight loss surgery? 

Your GP can assess you to see if weight loss surgery is right for you.

To be considered for weight loss surgery on the NHS, you should have a body mass index (BMI) of:

  • 40 or more
  • (or) a BMI of between 35 and 40 along with a weight-related health condition, such as type 2 diabetes or high blood pressure

You can find out your BMI by using our Healthy weight calculator.

You should also:

  • be able to commit to long-term follow-up appointments after the operation
  • have tried to lose weight by changing your diet and exercise levels for at least six months
  • be healthy enough to have an operation under general anaesthetic  

Even if you pay for private surgery, it's still likely that your surgeon will only agree to the operation if similar criteria are met, because of the risks associated with such major surgery. 

What does the operation involve?

Before the operation
If your GP thinks that weight loss surgery is right for you, you’ll be referred to a specialist weight loss team.

A consultant will assess you to decide if weight loss surgery is the right step to take. The consultant should explain more to you about the different types of surgery. They should also discuss the weight loss that can result, and the changes to your lifestyle that you will need to make afterwards.

They will also discuss the risks and possible side effects of surgery. Weight loss surgery is carried out under general anaesthetic. Serious complications with general anaesthetics are rare, but can be more likely when you are overweight.

If you and the specialist team decide to go ahead with surgery, you should be offered ongoing psychological support and help with changing your diet and lifestyle before the operation.

Many people who undergo weight loss surgery must go on a special, very low calorie diet before having the surgery. This is meant to lose the excess fat stored in the liver, so that surgeons are able to carry out the operation. It's important for you to meet a dietitian who can help you with this diet, and it is essential that you stick to it.

Having the operation
The type of weight loss surgery you have will depend on your circumstances, including how overweight you are and any other health problems you have.

Most people who have a gastric band operation stay overnight in hospital, but this varies between treatment centres.

With a gastric bypass, the stay in hospital is typically between one and three nights.

After the operation
Your specialist team should schedule several follow-up appointments running across a year or more, and it is important that you attend all of them.

This ongoing specialist team support is vital to the long-term success of the surgery, because it will help you to change former eating habits, and to adapt to a new lifestyle.

Remember, after your operation you will never again be able to eat as you did before. This means changing your eating patterns. A dietitian in your specialist team will be able to help you with this.

They will give advice on a healthy diet and supplements that will provide you with the nutrients and energy you need.

If you were fitted with a gastric band, it may be necessary to adjust it. This is done by injecting fluid into a small port that sits underneath the surface of your skin, and if necessary it will be done at follow-up appointments.

Following weight loss surgery, you will feel full after very small portions of food. You’ll need to eat small portions of food at mealtimes. It will take much longer to eat, and you’ll have to chew food very thoroughly. If you try to eat too much you may experience discomfort, or may vomit.

How long after surgery would I start losing weight?

Your weight loss will also be monitored at the follow-up appointments. If you have been fitted with a gastric band, you should aim for a steady rate of weight loss at around 1lb or 2lb (about 0.5kg or 1kg) a week, that continues for a year to 18 months.

If you have had a stomach bypass it is common to lose weight faster than this at first. But over time, the weight loss resulting from gastric bypass and gastric band procedures is the same.

If you were very overweight, you may not achieve a healthy BMI even once your weight loss has stopped. But moving closer to a healthy BMI will decrease your risk of serious health conditions, such as type 2 diabetes, heart disease, stroke and cancer.

Once you have recovered from surgery, exercising regularly will help you to achieve and maintain a healthy weight.

You can find more information and advice in recommendations after weight loss surgery


Page last reviewed: 24/10/2014

Next review due: 24/10/2016


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The 12 comments posted are personal views. Any information they give has not been checked and may not be accurate.

Gemini Lady1 said on 20 October 2015

I like many others have been struggling with my weight for many years. I have tried almost everything but it is an uphill struggle. My bmi is 50.5 I have asthma and borderline diabetes and have a minor breathing obstruction COPD . I have been back and forwards to doctors but I have problems sleeping when I sleep on my side my weight obstructs my breathing my back is pain all the time and my knee is also giving me problems I also get dizzy spells. On my last visit to doctors she said needed to refer me for surgery and was to ring the referral facilitation service is not heard in 3 weeks. I didn't hear anything and rung them to find out I had not been referred and to speak to my GP. I found out that i was supposed to have blood tests and blood pressure test. I did both. I received a call from the surgery asking me if i was on high blood pressure medication? i said no and i was asked to come in the following week to do a self service blood pressure and pass into reception. Long story short i spoke to my gp and she said that she had made a mistake and that i would need to meet certain criteria ie have diabetes (this was picked up on my blood test apparently dangerously high) oh and regretfully as my blood pressure normal very doubtfully i would get referral? i was caught at a bad time and couldn't talk and the gp kept repeating its something non urgent?, Basically looks like surgery backtracking and also trying to play down my high blood reading. Anyway i rang back spoke to another doctor who was very rude and said they would only be worried if my BP was 200 i told her i was not happy i was having headaches nose bleeds and keep feeling tightness in my right arm. I explained that both my grandmother and brother died of brain haemorrhages but not interested said my readings normal they were148 over 87 rested were normal.....i just give up

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bobbylad said on 09 September 2015

This page is offering incorrect advice.

I am BMI 45 and was told by the bariatric team that NHS England will not pay for any operations on people with a BMI under 50 unless they have spent 12 months on a Tier 3 Medical Weight Loss programme, something which does not actually exist.

So you need a BMI 50 not BMI 35 or 40 as this article suggests.

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ivy1930 said on 19 June 2014

hello there im 59 years old and due to have surgery . but ive lost 3 stone myself since October last year I was 26 st 4 pounds im now 23 5pounds do you think I should go for surgery or not advice please

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bekh said on 15 February 2013

I have struggled with my weight for many many years now and have tried everything I can to lose weight only to fail terribly. I was diagnosed with PCOS about 8 years ago and have been battling to bring the symptoms under control. I spoke to my doc many times and was finally referred to a dietitian. Her answer was to avoid the kitchen as often as I can. I stopped seeing the dietitian and just decided to keep on with the diets. June 2011 I moved to a different area and decided to speak to my new doc about my weight. She has become my angel and has given me so much support and advise I can't thank her enough. I was referred to a Live We'll clinic and was told I had to do a 6 month stint at the gym to help. I embraced it and did my 6 months (it wasn't easy believe me). I recently went back to see my doc for a check up and she is supporting me in applying for surgery. At 5'2'', BMI of nearly 50, nearly 19st, borderline diabetic and have PCOS, she is applying to the board for my surgery. If it wasn't for her support and kind words I don't know where I would be now. It hasn't taken 20 months to get to this point since I saw my new doc.

It was very upsetting reading people's comments about their docs lack of support. My first doc was like this and it pushes you back rather than helping you move forward. Please don't give up people. Contact another surgery to see a doc, you have a choice.

As hard as it is for me to be confident, I try everyday to embrace all I can. I may feel like a mess but I don't let people see that, I think that is half the battle of being over weight.

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fluffyjo said on 26 October 2012

I have a BMI of 47 and have been told i need to lose weight so i can have much needed surgery. I have fibromyalgia, chronic migraines, osteoarthritis a pro lapsed bladder (which is why i need the surgery) and severe depression. My gp referred me for weight loss surgery 2 years ago but i was refused due to the fact i didn't have diabetes. Apparently my PCT will not even look at your referral unless you are diabetic. So i feel like i am being punished for not having diabetes, surely it's better to do the surgery to prevent me getting it! I have very little mobility, i am on permanent crutches and i am having a wheelchair assessment in 2 weeks. I cannot exercise apart from the odd stretch whilst sitting in a chair. It's not my fault i cannot exercise, my health problems have caused it. Now my gp is putting all my health problems down to my weight and has said he knows i cannot exercise so i need to eat less. I barely eat now! I take a few mouthfuls and cannot eat any more. If i eat less i wouldn't eat atall. How do i make the PCT understand that surgery is my only option? I am also on medication which has a side effect of gaining weight, only been on it a few weeks and have already gained a stone.

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emmamelaney said on 04 March 2012

i have a bmi of 40 and its the lkowest it has been in 3 years. I would never consider surgery. people that generally have surgery see it as a quick fix but it isnt because you have to work twice as hard afterwards. my friend went through the surgery as a last result because she weighed 50 stone comfort eating depression and everything now she says she wish she didnt because she feels faint all the time. she is down to 20 stone but wishes she did what i do and go to fitness classes even simple little circuits and just have fun and start enjoying yourself. this really should be a last resort i would never consider it i want to loose the weight myself and I am

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ohcarol said on 01 August 2011

I weighed about 9 stone 10 until I had hypothyroidism that went undetected for 6 months. In those 6 months I gained 4 stone and although I take thyroxine every day I am still very tired and still gain weight constantly. I am now 15stone 14 and loath myself. I tried all the healthy eating that once helped me lose 3 stone and nothing worked. I don't eat (or like) chips and fried foods (yuk) nor do I have butter on my bread I don't have sugar or sweeteners and the most bread I eat in a day is 3 rounds still I didn't lose weight ...not even a measly pound. So now I've taken to binge eating on sweets.
I have been trying to make an appointment for the weight loss clinic and have telephoned 4 times
1st time - the computers were down and they took my details to call me back I waited over a week but no one called
2nd time - it was the wrong day so I was given another number that didn't get answered.
3rd time I spoke to someone the computers were broken and they would make me the appointment and send it to me. She argued that it was not their error and must have been someone else's error. She informed me it would be August for my 1st appointment and I would get a letter. I had to bite my tongue
Yesterday I received a letter I was so excited finally I was going to get help but no such luck the letter was saying 'our records show you have not booked'
So I gave it one last try by trying to book online only to be informed that I had to call the number.
Not great when you hate yourself so much - each time is a slap in the face.
3 weeks ago I was positive I set myself new targets and was looking forward to my new life but now I have totally lost faith in any help they claim to be able to give. I just feel like a huge person who overeats and so its my fault
Thanks to them today I threw out all my size 10s 12s 14s 16s 18s and 20s and resigned myself to the fact that I am going to be like this forever
Sorry about the miserable posting I just feel so depressed.

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fabulous fifi said on 01 June 2011

I have had 2 weight loss surgeries. and I am still 15st. I just expected the weight to fall off, but alas not. I had a non adjustable lap band with stomach staples which I had removed last year when I had my gastric bypass.
I am 1 stone lighter then I was which to anyone who has weight to lose is great, however I have a mental problem with food and think about it all the time. You have to be prepared in the head just as you are when you manage to lose a stone by being careful with your eatingl. Its not always the answer and its certainly not always the easy option.

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LindsayShepherd said on 01 June 2011

I have a BMI of 36.4 , not high i know, but my weight is affecting my health more and more.

I have followed weight watchers, i lost about half a stone the first 2 or 3 weeks then gained over a stone back

i followed slimming world, lost a few lb and then gained once i got into it

I was even put on the NHS Why Weight weight loss scheme.. it lasted 12 weeks, i did a food diary and everything, followed their advice on portion sizes etc, told my team leader about my limits on exercise because of existing health complaints so exercise was and still is an issue and something i can not do, and over those 12 weeks i gained nearly 2 stone.

I have also done the cerial diets, they didnt work, and iv done slim fast. which first time i did i lost 23lb in 8 weeks then christmas came and i gained weight again.. now im trying slim fast again and the weight is going on again, yet i move about a bit more than i use to because i do school runs for my children 3 times a day.

I am depressed because of my weight, to the point of self harm, i have been put on anti depressants by the GP but i felt like a robot on them so i stopped taking them.

I reciently went to see my GP to discuss help with my weight, and the dr gave me a funny look and his attitude changed instantly, he sounded rather cross with me and told me i was not fat enought for help. i explained the diets id followed and tried and told him about the depression which is in my notes on file, and he still said "your not fat enough" and hurried me out of the door.

now i feel like i dont want to visit the GP any more because of the way he treated me, i thought GPs were meant to be there to help, i asked for help and was brushed off with that comment.

is there anyway i can get the surgery on the NHS without having to get referal from my GP first, because he is just not willing to help me

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Bennyboots said on 10 March 2011

I keep trying to pluck up courage to ask my doctor for help. Whenever I see any of the doctors in the practice they seem to look down their noses at me as though my weight is something that I should just be able to sort out for myself. I have had a weight problem for most of my life and I have tried really hard to lose weight and keep it off but I cannot manage it. I am now suffering from depression because of my weight but I comfort eat because of the depression and it is just a vicious circle. I would love to find an understanding doctor.

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MaggzieP said on 02 February 2011

@amylove I had a BMI of over 50 in September 2010. I was referred and accepted for bariatric surgery on the 25th of September at 25.3 stone. I am 5ft 8 so you can imagine the looks I got from previous doctors to the one I have now (who used to be 24 stone himself once). The consultant said that apart from having PCOS, the weight is not affecting my health (as in being put under general, healthy heart etc). But, if I ever want to conceive, I need to lose it so that they can then help me with that. I think that its a case of finding a GP that truly understands, not just cops-out (yes there are a few out there), its taken me a long time to find mine. My mum has always been a larger lady as well and it took her years to find a doctor she was happy with too. I also think that they have a lot of pre-conceived ideas about larger people that they shouldn't. They shouldn't tar everyone with the same brush. It should be done on an individual basis. Now, as I have been told I will be put through for surgery if I can lose some weight in 6 months (next appointment in March), I have been absolutely killing myself to shift it as PCOS makes it even more difficult to lose anything and loads easier to pile it back on again and more. My BMI is now in the 40s and I am over a stone (18 pounds) lighter than my last consultation. I think that small steps give you a more realistic goal. Instead of being told lose 10 stone or we won't help you like before, the consultant saying lose maybe 2 and I'll put you through for the surgery, mind you will need to change your lifestyle for good has really made the difference. You don't feel as overwhelmed and you feel more supported and that gives you strength that maybe you didn't have before. I think everyone needs to have the chance to prove themselves and be helped with issues like these, and there just isn't the support out there unless you are very lucky and find a good GP/ Consultant. I would try and find a different doctor/ practice otherwise.

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amylove said on 13 January 2011

I have a BMI of over 50 and have been trying to lose weight for the past 10 years let alone 6 months and have been back and forth to the doctors for them to help me get surgery and they seem to not want to aknowledge my case so what else do i have to do?

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Vicky Finch

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