As we have discussed in previous articles, it is important that every patient who is planning to undergo gastric sleeve surgery consider the following:


  • Keep in close communication with your surgeon
  • To be informed and guided in the steps to follow before the procedure
  • Know the reasons why such suggestions are being made


Being one of the most important tips is undergoing a preoperative diet to shrink the liver size in order to facilitate things as far as possible during surgery.

If you don’t know why you should lose weight before any bariatric surgery such as the gastric sleeve we invite you to read first our  article: Why follow a pre-op diet when having a gastric sleeve surgery?


Regarding the need to reduce the size of the invariably enlarged liver in patients with obesity, it is very common to ask "how much weight should I lose or how to know if my liver size reduced enough?"


This is a difficult question to answer with certainty because each body is different and responds differently to low calorie intake.


Overall, what we seek in Obesity Free is for the patient to lose 10% of their initial weight, method that has worked in our practice in 100% of cases to reduce liver size to a degree that allows us to work properly. Some other practices will require an exact weight amount or exact duration of the diet. We rely on the individual case of each patient.



How long should I follow the preoperative diet?


Time will be determined by your bariatric surgeon depending on his/her experience and your particular case. In Obesity Free we focus specifically on the Body Mass Index (BMI) to determine how many weeks of diet the patient will require before surgery.


Patients who are BMI:

  • 35-42 are should follow a one week diet
  • 42 to 45 should follow a two week diet
  • For BMI’S over 45 we rely on the weight in pounds, say, if you weigh 300, would be 3 weeks, 400 lbs 4 weeks and so on.


We always insist our patients that in the months or weeks prior to their surgery  DO NOT have too many "last meals" as they would wish, since they enter a state of nostalgia which seems that they are saying goodbye forever to a lifetime friend, and we do not consider that they are necessarily wrong, however this may delay the process and the ideal timing for surgery because by being determined to have the gastric sleeve surgery they neglect what they eat prior to the procedure, they gain weight and when having to follow the preoperative diet it has to be longer than initially planned.


You may also be interested... 

18 Tips to prepare for Gastric Sleeve surgery


In Obesity Free we seek to help the patient realise that food is only an important part, but not the most crucial one, in the life of an individual. There is a very wise saying: "We should eat to live, not live to eat”


Something very important to highlight to avoid overestimating the apparent difficulty that sticking to the diet could be, and since for this and other reasons you are looking for help in weight loss surgery is the following:


  • It is practically the last diet that you will do in your life!. (In the postoperative phase of the diet the procedure will be your ally).
  • The benefit of following the diet to the letter is enormous, reducing the chances of complications during surgery and leading to a faster recovery.
  • It will help not only physically but also mentally in preparation, which is crucial as the beginning of a new lifestyle that includes a proper food quality and quantity.
  • Sounds hard to stick to a diet but certainly we can assume that you have done it previously and probably more than once, usually multiple times, the difference is that this diet itself will bring the results you’ve always desired.
  • No matter how strict the diet is (depends on the bariatric group you choose), it is possible. The first 2-3 days are the hardest, then, every day will get easier. (We say this advisedly from the experiences that our patients share with us.)
  • Doing the preoperative diet will also help you to have at home everything ready for your return after surgery because there will be no inadequate food in your refrigerator or pantry.


If you would like to have more details on what the preoperative diet consists we invite you to visit our article Gastric Sleeve Pre-op diet


The gastric sleeve procedure in México is totally safe, we invite you to get a free evaluation with us and share your questions about the gastric sleeve cost in México, side effects, etc, to


Written by: Gabriel Rosales

Dr. Gabriel Rosales is a highly skilled, board certified surgeon in constant pursuit of learning the latest innovations in the weight loss surgery field to give his patients the best care possible.