Cheating on Pre-Op Diet Before Weight Loss Surgery

Question Below Submitted By:  

Ella (a patient from NJ)

I’m having the gastric bypass done in less than a week and my doctor has had me on a diet of only fish, protein shakes, soups and jello for 3 weeks.

I want one last good meal… do you think they will cancel my surgery if I do? Would they even know about it? Is “cheating” with one last good meal dangerous – that is, would it increase my risk of complications?


Expert Responses to the Question Above

RE: Cheating on Pre-Op diet before WLS

by: Arif Ahmad, M.D., F.A.C.S., F.R.C.S.

Hi Ella,

The surgeon will not know if you have one "cheating" meal. However cheating is a bad policy for your own well-being and success with weight loss surgery.

Weight loss surgery involves a long term relationship whose integrity is dependent on mutual honest and frankness. It is far better to address this question with your surgeon and get his or her approval for any action you plan to take.

This surgery is not about deprivation. Rather the key is earlier satisfaction. There is no such thing as a "last meal".

Patients who are honest with their surgeons lay down the foundations of their own success and are able to continue to enjoy normal meals for the rest of their lives.

I wish you the best of luck with your weight loss surgery and hope it leads to a healthy happy lifestyle,

Arif Ahmad, M.D.

long island bariatric surgeon

(click here for Dr. Ahmad's full bio & contact info)

DISCLAIMER: This educational advice is based on the depth of your question and the details provided. The above should never replace the advice of your local physicians as they have the ability to evaluate you in person.

Related Pages:
- Bariatric Diet (What you eat)
- Bariatric Eating (How you eat)
- Bariatric Vitamins


Patient Responses to the Question Above


by: Mary

If you are planning on cheating now, you are not a good candidate for surgery. Having had the surgery successfully nearly 10 years ago, I can tell you it is not magic. You will forever have to watch what you eat and exercise. And yes, you will be able to cheat and will gain your weight back after your surgery. If you want to be successful, you may wish to examine the reason you want to cheat so badly. That is something you will need to deal with head on.

Response about smoking

by: Jeff

Hi Anonymous, Please see this post about smoking before and after weight loss surgery. I hope that helps, and good luck! Jeff

Related Pages:
- Bariatric Surgery Complications
- Bariatric Surgery Risks - Mortality


by: Anonymous

I have a question . I have surgery set for 07/21/2015. At the time I set up all this I didn't smoke as much maybe 5 a day..but I started smoking a pack a day.will this hurt my surgery? Should I cancel it?

Don't Cheat....It's NOT worth it!

by: Anonymous

Don't cheat, it's not worth it! If you cheat now, you will cheat later...if you wanted one last good meal you should have done so before the implementation of the Stage II diet.

High fat foods and "solid foods" can increase the thickness of your liver which can make it more difficult for your surgeon.

Difficulties in surgery moving your liver, means longer time under, which can lead to more issues.

Your surgeon is giving you a "GIFT" by helping you change and enhance your life, don't make it more difficult for him/her.



by: Anonymous

i was reminded that i was suppossed to be dieting 3 days before my sleeve surgery and wonder if they will cancel my surgery because of it or how it will affect me during surgery...

Why would you do that?

by: Rosanne

You are only hurting yourself by doing that! After the surgery it is not like you can't ever eat what you want again... after about 8 weeks or so when you feel better with regular food again, you will start to see what your system can tolerate (everyone is different).You can eat whatever you want little by little, but I guarantee your taste will change in the foods you like! If you eat something that you used to love you might find out it is not for you anymore. For me it is beef.

It seems like it is just too heavy for my stomach now. And I used to hate fish unless it was fried, now I don't like fried foods and absolutely love fish fixed any way BUT fried! I don't know how the change in food taste works but it does change after Gastric Bypass. You will be able to eat again just in moderation. Good luck with your surgery. I had no problems at all and neither did my husband. I had mine about 1 1/2 years ago and my husband had his just 6 months ago. We both are doing great!! Best thing we ever did for ourselves!! Again, Good Luck

Getting back on track

by: Gina

I had gastric bypass about 4 years ago, moved to a different state and have since gained back some weight. I do not have insurance so I am not able to see a doctor about this. Does anyone have the pre-op and post-op diet ?

Cheating before surgery

by: Kim

I am having surgery and want to know the same thing. Will it cancel surgery if you cheated a little even though your still doing the shakes and 64 ounces of water?

Be grateful

by: Anonymous

Great that you can have fish.

I am having the sleeve on 10/27 and I can not have no meat at all protein shakes, water, broth, sugarless popsicles, and 1 cup of fresh vegetable.

weight loss before surgery


I recently had my bariatric consultation and the MD and I decided that sleeve surgery would be the way to go.

I am at a BMI of 36.

After my consultation I was sent to see a nutritionist to talk about healthy eating and start on a diet.

At this meeting I was told that if I lose 5 lbs I will no longer be eligible for surgery.

She instructed me to NOT lose weight.

Is this true? If you fall below 35 prior to surgery you no longer qualify? So if I get sick the week before my surgery and happen to lose 5 lbs I can't have the surgery?

Duodenal Switch

by: Richard

I'm having surgery in one week. I'm started my pre-opt diet one week ago. I admit I have cheated a little. I have had soup and an apple on occasion. I'm still taking my required protein shakes and protein drinks as prescribed, an well as my vitamins. I'm scared, but I've been so weak. I don't want to be cancelled out as a patient for my deed. Please help?

2 Weeks Before Surgery

by: Coming Up

I have seen on the internet and on this site prerequisite four surgery. I am two weeks before surgery on an entirely liquid diet. Period.

I have approximately 60 G of a protein shake a day and no less than 64 oz of water a day and only broth. What are you people talking about eating anything at all?? Then after surgery along with all the other medical things that I have to see to, for the next 3 weeks after the surgery I'm still on an entirely liquid diet.

Now, that seems a bit harsh to me. But from what you guys are saying you are all eating before the surgery. And I assume after the surgery. Is anyone else using the instructions that I was given for the before and after diet for the sleeve surgery?

My surgery is set 4 January 30th. I've been on a total liquid diet for 8 days now. I'd just like to eat an egg white or something.

All I want is a Donut

by: Donte

5 Days Pre-OP and all I want is 1 stinking French Cruller. Would that be so bad? Can my doctor tell?

by: Patrick Furlong

It's a good idea not to cheat... Build your habits now so you're ready after surgery.

5days till surgery

by: Bea

I am so thinking about getting up and putting me 2 pieces of catfish in my air fryer because i am so freaking hungry!!!

Ughhh I eat Jello or eat a popsicle to get over my cravings.... Will it hurt anything if I eat that just for today?

All liquid diet

by: Momuv4

I to have an all clear liquid diet was supposed to have 4 weeks of it but escaped a week, Im supposed to only have 2 protein shake sugar free jello sugar free pudding and light yogurt. Oh yes, and the freaking popsicles!

I'm over in only have about 11 days till my surgery and I hope I didn't blow it today but going strong for the rest of the days hopefully reading everyone's diets I didn't blow it and my liver will be I wish I could have fish and salads lol


by: Carleen E Perry

I'm on my 2-week liquid diet and all that I can have is sugar-free popsicles, water, Premier protein shakes, sugar-free Jell-O and broth.

I don't know how you guys are able to have food..I would love to have vegetables..I was told by my Dr that I could only do a liquid diet.. and the same thing after surgery

VSG Preop diet

by: Sleevedlei

So per my surgeon I am on a two week preop diet that contains the following:
3 meal replacements 180-200 calories & 15-20g of protein each
1 “Real food” meal

I was given a list of free foods (raw veggies, sugar free jello, broth) that I can eat in any amount through this diet. And a recommended 1000 food menu to compile my real food meal. I’m allowed 1 real food meal a day up until 5pm the day before surgery then clear liquids after 7 no liquids after midnight.

Sooooooo my surgery is scheduled for 4/17/18. On 3/30/18 I got a call from my surgeons office that there has been a cancellation and I could be sleeved the following Monday 4/1.

I expressed my concern of lack of preparedness and that I wasn’t on a preop diet and was told not to worry about it, that’s just ideal conditions......

Ultimately I passed on the earlier date because obviously I want ideal conditions when being operated on but now the lack of emphasis on the pre op diet is lingering over my head and I find myself eating a protein cookie (full of carbs) to satisfy my sweet tooth.

FYI I’m on day 3. Just wanted to share my experience as I see so many people on strict liquid diets for 14 days and I’m able to eat a full meal


by: Di

My surgeon was super strict. My diet was super strict. For two weeks I was allowed protein shakes. Broth. Sugar-free gelatin and sugar free popsicles. That's about it.

For three weeks after surgery the same thing. The next month there was a little bit added but nothing that was enjoyable trust me. Then the next 2 months I am on Turkey, poultry, some veggies. I don't know what in the world the rest of the people are.

They have all this food to eat. So, until May 16th I'm able to eat a little bit more than the broth. But as I said that's just your poultry turkey eggs broiled, baked, fricasseed (😉) protein. Absolutely nothing ride. Oh I can also have string cheese. That's about it.


by: Di

My weight loss is going very well. My advice to before-surgery would be to research what the protein shakes and the vitamin B12 are to your body.

I knew that it was beneficial to my body but I didn't realize just how much. That being said immediately after my surgery I kind of cheated on the protein shakes. However once I researched the protein shake and its benefits I began to use it everyday in the amount that I was supposed to ingest.

The other thing I did not know was about to vitamin B12. I did not know to not swallow it -not knowing that it should have been placed under my tongue. After research I realize that I've been checking it and the wrong way and corrected it.

Pre-op diet

by: VAAubrey

Hello I’m on day 6 of my 2-week clear die, today is June 2nd im having my VGS in 8 days. On my pre-op diet I can have the norm Prtein shakes, broth, popsicles and jello. But I can also have Epic protein bars which is basically a fat piece of Beef Jerky. So I’m glad of that because some of you seem to be on a hard liquid diet. I did slip up and eat some tuna 5 days In I hope that won’t be that big a deal. I would say to everyone first of all MYSLEF remember why we have decided to take this step.

I'm also on a two week liquid diet

by: Eddie

So how did it go when u ate a meal before ur surgery? They they do the surgery and they it when well?

Asprin one time before surgery

by: Elaine

Will my gastric sleeve be cancelled if I took 2 Excedrin 4 days before my surgery? I am so scared they will cancel it!

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