The gastric sleeve surgery is an excellent procedure that relatively just a few years after being approved as a primary bariatric procedure has gained much popularity.


Unlike other methods which are also in demand by patients, the gastric sleeve has not made use of huge marketing investments from medical companies such as other procedures involving the placement of devices like as the gastric balloon or gastric band.


The popularity of the sleeve gastrectomy may be said to have won it "on its own" thanks to the great benefits that offers and the low rate of complications in the short, medium and long term when compared with other more invasive procedures such as gastric bypass  or duodenal switch.


But like any other surgical procedure in bariatric surgery, has its advantages, which we can discuss at another time, as well as its disadvantages or gastric sleeve side effects. We really do not believe that they should be seen as disadvantages because they are situations or changes that are completely controllable and manageable. In addition, when placing on a scale these advantages and disadvantages, the positive aspects are much more in favor of the decision to undergo this procedure full of benefits.


These gastric sleeve side effects are related to changes that are natural consequences of manipulation and changes made to the structure of the gastrointestinal tract. But most of these side effects are associated with poor patient compliance of the doctor's instructions. Which in many cases is not the patient’s fault but from surgeon itself who does not provide information on how to prevent such gastric sleeve side effects in a timely or appropriate manner.


This is why we insist that no matter who you decide to choose as your surgeon for your gastric sleeve operation, you should make sure that he/she provides adequate monitoring and all "weapons" necessary to prevent or combat the side effects.


We could classify the gastric sleeve side effects in two types: the ones related to the procedure itself and the ones related to inadequate guidance from your surgeon.



Content of this article:
Side effects proper of the procedure
Partially or totally preventable Side Effects of Gastric Sleeve
Classification of the gastric sleeve side effects by display time or duration



Side effects proper of the procedure

There are really very that can be listed and that is why we are great supporters of this particular procedure.


Gastroesophageal Reflux

Gastroesophageal reflux is a common condition in the general population which may have varying degrees of severity. In the specific case of obese patients, excess weight is the main factor to be considered as the cause of reflux.


Patients who wish to undergo gastric sleeve surgery and have severe reflux should consider the option of selecting another procedure such as the gastric bypass. Should you undergo gastric sleeve procedure, relevant preoperative evaluation should be performed in order to discard that the gastric sleeve operation will cause you to have even more severe symptoms related to reflux.


The reason why the gastric sleeve operation causes gastroesophageal reflux is simple: in the immediate postoperative period and mediate (let’s say the first 6 months) will be the periods when this symptom will be most notorious and this is due to the drastic change in the capacity of your stomach and that this organ will pass from an approximate capacity of 1500 cc (cubic centimeters) to only 90 cc after the procedure. This causes the acid produced by your stomach has some difficulty staying there without climbing, reflux, into your esophagus.


In addition, some experts in the physiology of the stomach argue that after the procedure there is a significant and sudden decrease acid production so the remnant stomach tries to compensate by over-producing acid. That is why the first few months is when this symptom occurs more intensely.


However, as months pass by after surgery, usually this gastric sleeve side effect gradually diminishes, the body and specifically the stomach adapts to this new shape, dimension and physiology and stops producing excess acid, besides the patient’s progressive weight decrease, that obesity is no longer present and therefore this factor ceases to exist. Allowing the patient to be free of reflux or at least be at a much lower level than it was before surgery and can be controlled with simple and occasional medical treatment , like everyone else.


The main recommendation to avoid this situation is to stick to the gastric sleeve post-op dietprovided by your surgeon and to avoid foods that will cause this symptom just as you would if do before surgery.


Since the goal of undergoing gastric sleeve surgery is to lose weight and eat less, logically it is important to focus on not eating more than what your sleeve allows you to, in other words, stop eating when you have a feeling of fullness and not when you feel "you just can’t have another bite anymore" because even though in the end, the amount of food you can eat after gastric sleeve is much less, you would still continue to overfill your stomach despite its reduced dimensions.


Finally it is said according to several medical papers and surveys, that less than 20% will continue to have some reflux 6 months after surgery to a variable extent.


You may also be interested... 

Is it safe to get gastric Sleeve in Mexico



Mild taste alterations

This situation is much less common than the one mentioned above but still sometimes occurs as a side effect after gastric sleeve surgery.


This fact has no clear scientific explanation, it just happens. Some patients perceive a change in the taste and smell of certain foods after the procedure.


The good news is that these changes are favorable in the sense that their perception of what was once thought of as "sweet" now perceived as "too sweet" and the same with the "salty" food. Viewed from the perspective of health and healthy eating, what better than sensing that what is sweet and high in calories that you used to like before surgery is now just too sweet to have it. The same with high sodium food which is unhealthy, you will also feel like avoiding it.

On this side effect there is no specific way to prevent it, but this fact plays in your favor.


Decreased tolerance to cold

This gastric sleeve side effect is not unique to patients who have gastric sleeve surgery but to any effective bariatric procedure, what happens is just that the natural insulation from body fat you had before surgery no longer exists.


Body fat has a secondary function as a natural insulation against low temperatures, avoids cold from penetrating your body. Then when you loose all those extra pounds, almost all of them come from the loss of body fat, both exogenous and endogenous (fat under your skin and fat between your organs); which diminishes your ability of insulation to cold and will be perceived as an increased sensitivity to low temperatures.


How to prevent it? Really the only way to avoid this is to wrap up well in cold weather, if you think about it is a situation that is completely worth to "suffer" as it is because it'll reflect that you are much healthier with those less pounds in your body and is completely controllable with good layers of clothing.


Reduced alcohol tolerance

This issue as we have previously discussed in other sections of our blog, so we shall not dwell much on it. We can only suggest that you see it as with the case of the change in taste:

The fact that your ability to tolerate large amounts of alcohol is diminished is simply a very favorable side effect in all respects, both in the sense of health to not being able to drink too much alcohol and the fact that we sometimes joke with our patients: from now on their "you’ll be a “cheap drunk"!



Partially or totally preventable Side Effects of Gastric Sleeve

These side effects unlike those mentioned above, can be prevented if the patient adheres to the suggestions of food and lifestyle given by your surgeon.


Hair Loss

This is one of the most common concerns of patients who undergo gastric sleeve surgery or any other bariatric procedure. This is totally understandable because although the hair is not vital to our functions, the vast majority feel uncomfortable with the idea of losing it.


In the specific case of the gastric sleeve procedure, wherein an alteration in the absorption of ingested nutrients by the patient is not altered, there is no defined medical reason why the patient should lose hair. Although, we know that a significant percentage of  gastric sleeve patients do lose hair, but in most cases this is because they do not follow the diet properly and neglect the quality of the food they eat after surgery.


Usually, if the patient is compliant, ingests recommended vitamins and supplements during the first 12 months, and also eats good quality food he or she will not lose hair. The patient that has undergone gastric sleeve surgery and takes his/her vitamins and supplements irregularly, that does not give priority to high protein foods and nutrients and fills the stomach with junk food, is the type of patient who will definitely lose hair in some extent.


A small percentage of patients suffers hair loss despite following the recommendations but that percentage is very low and just temporary, all happen to see an almost full recovery of such hair loss.


If you wonder how long does hair loss lasts after gastric sleeve surgery, if you are one of those rare patients with this situation, it is likely that at after 12 to 18 months, your hair will be as before the procedure



Nausea and vomiting after gastric sleeve surgery

Nausea and vomiting are common symptoms in any patient who is subjected to a major surgical procedure and even more so when that it involves the manipulation of the gastrointestinal tract and is performed under general anesthesia.


So, in summary, it is expected that this symptom to be present in some extent. The important thing is to remember that these symptoms usually do not last more than 24 to 48 hours after surgery.


There are situations in which the patient despite receiving appropriate support in relation to information on how to feed and how to follow the postoperative diet, do not follow these instructions and this leads him/her into a vicious cycle of nausea and vomiting which produces swelling of the gastric mucosa and this in turn increases food intolerance. This situation is completely preventable if the patient follows the instructions strictly.


If a patient suffers from severe nausea or frequent vomiting, postoperative diet of the gastric sleeve is followed properly and she/he is not in the immediate post-operative period, should contact the surgeon to rule out any situation requiring medical attention.


In rare cases, when the procedure is performed by inexperienced hands, a situation known as "stenosis" or "kinking of the gastric sleeve" can be present, in simple terms, it is a partial or total obstruction of the stomach to passage of food or even saliva to the intestine due to an inadequate technique at the time of the procedure. Unfortunately, this situation usually requires something more than medical treatment, being necessary periodic treatments done by endoscopy.



Changes in bowel movements and diarrhea after gastric sleeve porcedure.

This situation is largely similar to that described above because if the patient adheres to recommended food by your surgeon, the chances of it lasting more than a few days are very low.


The first days after the gastric sleeve surgery, the first bowel movements may be liquid or semiliquid and this may be due to several factors such as the manipulation of the gastrointestinal tract that may cause the presence of small quantities of blood and this causes some irritation, besides the fact that in theory all patients after gastric sleeve will be in a liquid-based diet so it is hard to think that their movements will have a solid consistency.


However, this is something that after a couple of weeks after the operation will be fully resolved and if it does not, you will have to consider whether you are following the diet as it was indicated.



Lack of energy after gastric sleeve surgery

The patient’s sensation of tiredness and lack of vigor after surgery is very common. Most show some fatigue in varying degrees the first few days after the procedure and this is due to several factors.


The main factor involved is the fact that any surgical procedure represents a kind of "aggression" to the body, it is aggression in the sense that surgery causes release of certain substances that lead to significant changes during the first hours after surgery . Without wishing to go into too much detail as not to confuse more than help with complex terms, the body enters a state of catabolism (consumption and use of energy and nutrients) for several hours before recovering. This is a completely normal and expected reaction but involves energy consumption which in a patient who is on a low calorie diet, it will manifest as a drop in energy levels.


Fortunately this only lasts a few days, usually begins three to four days after surgery and the patient recovers in a span of one to two weeks after this, and after this, patients usually refer the feeling of having more energy than ever.


Probably you may ask why we categorize this effect within preventable, and the fact is that what we just described is what happens when the patient follows the instructions, since when it does not comply to the indications lack of energy may last several weeks before feeling enough energy or pass by intermittent periods of fatigue and energy, which is a completely preventable situation.



Classification of the gastric sleeve side effects by display time or duration

All the effects or situations that we have described in this article could also be classified as effects in the short / medium and long term, we list them under that concept below:


Short / Medium Term:

  • Gastroesophageal reflux
  • Hair Loss
  • Nausea And vomiting
  • Alterations in bowel movements and diarrhea
  • Lack of energy


Long Term:

  • Decreased tolerance to cold
  • Decreased tolerance to alcohol
  • Slight alterations in taste


If you already had the gastric sleeve surgery, tell us what other side effects you have experienced or still experiencing…..


If you have not had surgery yet and  plan to, which side effects do you know of apart from those mentioned and which ones do you fear developing?



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 our email: 


We invite you to read our most popular blog articles:


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.