Bariatric Surgery: last resort for obesity sufferers

The obesity is acquiring frightening proportions worldwide and causing much concern to experts, since it is major risk factor for the emergence of numerous chronic diseases.

In an attempt to reduce the incidence of obesity, it is advisable to take care of food and exercise regularly, however, in some cases, only these changes in the routine may not be enough.

Therefore, it is necessary that many people resort to bariatric surgery, as a way to lose weight more quickly, reduce the likelihood of diseases and consequently improve the quality of life.


What is bariatric surgery?

In a significant part of the cases, excess weight occurs due to an unhealthy routine.

Bariatric (and metabolic) surgery is the term used to define methods developed for the purpose of reducing the stomach and thus facilitating weight loss in patients classified as obese.

Obesity over the years has become one of the biggest public health problems in Brazil.

According to a survey conducted in 2019 by the IBGE (Brazilian Institute of Geography and Statistics), 1 in 4 people in the country (aged 18 or over) has some degree of obesity, which corresponds to 96 million people .

In general, the main cause is carelessness with food and the practice of regular physical exercises, however other factors can interfere with hormonal changes

Excess weight is a cause for concern due to a number of diseases that can be caused in the individual, such as high cholesterol, diabetes , sleep apnea , hypertension, urinary incontinence, among others.

These diseases consequently affect health and quality of life, and can even cause death.

Thus, many seek bariatric surgery as an alternative to reduce excess weight and avoid future complications.

The main factors that influence the procedure are:

  • BMI: the acronym corresponds to the Body Mass Index, an international measure that is obtained by dividing the weight by the square of height. In general, when this result is above 30, the patient is obese (grade 1);
  • Comorbidities: these are one or more diseases that come from the same “source”, that is, excess weight is the reason for other diseases that are affecting the individual. These comorbidities can be classified as mild, moderate or severe;
  • Age: those in the age group between 18 and 65 years old can usually perform the surgery without any restrictions, however those over 65 years old are considered more fragile and therefore the procedure presents a higher risk. In relation to children and adolescents, bariatrics can only be done with the consent and monitoring of family members.  

Although these are the main criteria for assessing the patient’s ability to undergo surgery, each person presents a unique clinical picture. Therefore, there are a number of situations that may make the procedure possible or not.

Because of this, the person undergoes evaluations with different health professionals.

Some of them are:

  • Endocrinologist: in many cases, overweight occurs due to difficulties that the body has to metabolize fat and sugar. In this way, the specialist will indicate bariatric surgery as a way to reduce weight and alter the individual’s metabolism;
  • Cardiologist: some people who intend to have surgery have problems such as hypertension and heart failure, so this specialist will certify that these diseases will not affect the performance of bariatric;
  • Pulmonologist: due to being overweight, patients may have developed respiratory and pulmonary complications, thus, the professional will do preventive exams to certify that there are no risks for stomach reduction surgery;
  • Nutritionist: will define which diet should be followed during the period before the surgery and also what should be the dietary routine after the intervention, avoiding the risk of the patient becoming overweight again;
  • Physiotherapist: this professional will help in recovering the patient’s motor coordination after the procedure and will also guide (together or not with a physical educator), the exercises to be done so that there is no weight gain again;
  • Psychologist: essential to ensure the mental health of the patient who needs attention due to the surgical process, which is very complex and requires a series of changes in routine ;
  • Bariatric surgeon: responsible for guiding the best technique for stomach reduction and performing the procedure.

It is important to highlight that these professionals are essential not only before bariatric surgery, but throughout the surgical process and after it. Because stomach reduction is considered a complex intervention and requires changes in habits in the patient’s life.

In addition to consultations with several specialists, tests are prescribed to help certify that the patient is in a condition to have the surgery.

What is the difference between bariatric surgery for stomach reduction?

In reality there is no difference between the two terms, as bariatric surgery is the name given to the techniques that can be used to reduce the stomach and consequently facilitate weight loss. In general, these techniques can be classified as restrictive, disabsorptive and mixed.

What types?

In general, there are three ways to perform bariatric surgery: in a restrictive, disabsorptive or mixed manner.

In order for the different types of bariatric and metabolic surgery to be more easily understood, specialists have divided it as follows:


The restrictive surgical intervention, in addition to decreasing the amount of food that the stomach is capable of supporting, also alters the feeling of satiety so that the individual is satisfied faster.

This is done by surgical cuts made to remove a large part of the stomach, and thus give it a new shape (tube).

In some cases, a restrictive surgery can also promote the reduction of appetite, being classified in addition to being restrictive, a metabolic procedure.


The surgeries considered as disabsorptive are those that do not make significant reductions in the stomach, but deviations in the intestine (mainly the small intestine), causing the absorption of food to be reduced.

This consequently causes weight loss, since food undergoes a relatively short period in intestinal transit.

Whoever performs this type must be careful with the amount of micronutrients as vitamins present in the body, which usually decrease due to the intervention.


Mixed procedures are the most indicated in general by specialists, as they have a high level of satisfaction for the patient, reduces the chances of diseases linked to obesity and facilitates the maintenance of reduced weight after surgery.

The intervention is considered mixed, due to the association of the reduction of the stomach with the diversion of the intestine, managing to decrease the capacity of the stomach to receive food and shorten the intestinal transit simultaneously, promoting weight loss.

How is bariatric surgery done?

Bariatric surgery will be done according to the technique defined by the specialist doctor in agreement with the patient. In general, the patient will be admitted to the operating room, where the surgeon will perform the procedure through videolaparoscopy (incisions from 0.5cm to 1.2cm) or open laparotomy cut (from 10cm to 20cm).

The following techniques that are often used in Brazil:

Gastric bypass

Classified as a mixed technique, gastric bypass or gastroplasty with Roux-en-Y intestinal deviation is done using a kind of clamp to hold part of the stomach, thus reducing its capacity.

In addition, a small deviation is made at the beginning of the small intestine, so that hormones that induce greater satiety and consequently decrease hunger are released.

The gastric bypass technique is the most used in the country, since about 75% of the procedures occur through this method.

One of the reasons that justify the choice is that it manages to make the patient lose 70% to 80% of excess weight, effectively and safely

Vertical Gastrectomy

Taken as restrictive, the vertical gastrectomy, also called sleeve or shirt sleeve gastrectomy , transforms the stomach into a tube with a space of 80 to 100 milliliters for food, as it removes part of the organ.

Because it is considered a surgery that alters the metabolism of the digestive system, it is recommended for patients who have diseases that need to be controlled, such as high blood pressure and cholesterol.

In relation to weight loss, the result is satisfactory compared to Bypass and superior, in the case of the adjustable gastric band technique.

Duodenal switch

This technique is similar to that of a vertical gastrectomy (or sleeve), but a small intestinal deviation is added.

To do this procedure, part of the stomach (about 60%) is removed and another part (even larger) of the small intestine as well.

Thus, in addition to the initial weight reduction, which is usually 75% to 85%, most of the food eaten will not be fully absorbed (since the intestine responsible for this has been reduced), causing weight loss.

Adjustable gastric band

Since the technique is less used today, due to technological advances that have allowed the emergence of other methods considered more adaptable, the intervention of the adjustable gastric band is performed in only 1% of patients in the country.

However, its effectiveness is considerable as it initially reduces from 50% to 60% of the individual’s weight, however it is less compared to other techniques.

This bariatric model is made by means of an adjustable silicone ring, placed around the stomach to tighten it and thus reduce its size and the ability to receive food.

Who can do it?

It is necessary to calculate the body mass index to know if the person is fit for bariatric surgery.

According to the Brazilian Society of Bariatric and Metabolic Surgery, patients who have:

  • BMI between 30kg / m² and 35kg / m²: you will only be fit for the procedure if you have serious illnesses linked to excess weight diagnosed by the doctor.
  • BMI between 35kg / m² and 40kg / m²: if you have any associated disease (comorbidity), which can be classified as mild, moderate or severe.
  • BMI above 40kg / m²:   even if you do not have a disease linked to excess weight, you can perform the surgery.

However, just fitting into any of the above classifications does not make the patient in perfect condition to perform the surgical intervention.

It is important to emphasize that this is a procedure considered as a last resort for weight loss, due to the surgical complexity, health risks after the intervention and radical changes that must be adopted after the process.

What is the minimum weight for bariatric surgery?

The minimum weight to perform bariatric surgery is 108 kilos, up to 1.75 in height, which is equivalent to a BMI above 35 kg / m² (grade 2 obesity). However, weight in itself does not define the individual’s eligibility to perform the procedure, since it is necessary to assess the clinical condition and to know if there are diseases (or if they can arise) due to being overweight.

In addition, the candidate must have tried other methods guided by specialists to reduce weight, such as diets, physical exercises and medications.

How long does bariatric surgery take?

The duration of bariatric surgery depends on certain factors, such as the surgeon who will perform the procedure, what type of bariatric surgery will be performed and whether there will be complications after the surgery.

However, in general the estimated time for each bariatric technique is:

  • Bypass: 1 hour and 30 minutes.
  • Vertical gastrectomy: 1 hour.
  • Switch duodenum: 3 hours and 30 minutes;
  • Gastric band: 30 minutes.

How is the post-operative?

The change in dietary routine is one of the most significant changes after bariatric surgery.

If preparation for bariatric surgery is essential for its performance, post-surgical care is crucial for the success of the procedure, especially in the long term.

Thus, some guidelines to be followed according to the Brazilian Society of Bariatric and Metabolic Surgery by the patient undergoing surgery are:

Food routine

Food is one of the areas most affected by bariatric surgery due to a stomach reduction that limits the amount of food, so care with it is paramount.

As soon as the newly operated patient arrives at the hospital room, he can start a diet composed of liquids and eat meals according to the interval determined by the nutritionist.

In general, it is also recommended to drink at least 2 liters of water per day for the first few days after surgery, to avoid problems such as dehydration, kidney stones, thrombosis , among others.

As the days after the surgery go by, the nutritionist will make changes to the prescribed diet, indicating a mild feeding routine until the normal routine with any food (which is nutritious and healthy).

Attention to symptoms

Although bariatric surgery techniques are safe and the patient has undergone several assessments before the procedure, complications can still arise in some cases.

It is important to note that having symptoms after the intervention, such as pain and swelling is common, however, when they do not stop even with the medications prescribed by the doctor, this can be a warning sign.

When this occurs, it is necessary to consult the doctor who performed the surgery quickly, so that he can check what is causing such intense discomfort, or also some symptoms that were not expected.

Thus, it is possible to diagnose the problem early and avoid further health complications.

Replacement of micronutrients

Most bariatric surgery techniques, in addition to stomach reduction, also alter the small intestine, responsible for the absorption of nutrients.

Therefore, it is necessary to supplement, that is, replace nutrients that are not being absorbed enough by the body through food.

In general, the most common nutrients to be replenished are vitamins, mainly from the B complex and mineral salts such as iron, to prevent anemia , and calcium, to preserve bone density.

The amount to be ingested depends on the nutritionist’s guidance, which may be higher during the first days after surgery, and thus be reduced as the food routine advances.

What are the risks of the operation?

Although bariatric surgery is considered complex, it is a safe procedure according to the Brazilian Society of Bariatric and Metabolic Surgery.

Problems that may arise are usually diagnosed during the preparation for surgery and all information is transmitted to the patient, who together with the doctor will determine whether it is appropriate to perform bariatric surgery or not.

For this reason, preparation with a multidisciplinary health team is essential, since each one will provide guidance according to their specialization, reducing post-surgical risks.

However, some unexpected complications may arise after the procedure, such as:

  • Incisional hernias: bariatrics performed mainly by open cut (laparotomy) can damage the internal wall of the abdomen, displacing organs into the region where the surgical incisions were made;
  • Gastric Volvo: occurs when there is an obstruction of the passage channel of food or feces, due to a twist in the intestine;
  • Iron deficiency anemia: if minerals, such as iron, are not correctly replaced, patients, especially women (due to blood loss due to menstruation), may present this condition;
  • Osteoporosis: the drastic weight loss can damage the bone structure, since it was used to a greater load, so, in addition to the replacement of important minerals for bone tissue in these cases, physiotherapeutic activation is necessary;
  • Psychological traumas: people who have put on weight due to disorders such as binge eating and anxiety have more difficulties to get used to the new image and also to changes in eating and physical routine, so it is recommended to visit the psychological during the period that is required.

Health insurance and SUS: where can I do bariatric surgery?

Bariatric surgery can be done through the Unified Health System (SUS), health insurance and private individuals.

Whoever wants to do it by SUS, must make an appointment with a doctor (a) specialist belonging to the system that will assess the condition and request surgery.

If the application is approved, the patient will join the queue behind other people who have previously requested the procedure. If your situation is considered to be more urgent, it may happen that the intervention will be carried out more quickly.

Now, whoever wants to do bariatric surgery through a health plan, should check with the person in charge of the contracted company to check if the surgery has coverage (whether partial or total).

What is the average weight loss after bariatric surgery?

The expected average weight loss after bariatric surgery will vary according to the technique used and the patient’s recovery. However, considering the two most widely used methods of invention in the country, gastric bypass and vertical gastrectomy, it is estimated that the patient loses 800g to 1Kg per day after the procedure.

This is due to the first 12 to 14 months after surgery being considered the “gold” period, that is, the phase in which he loses the most weight. However, normally when that period passes, the weight reduction is less.

Price: how much does bariatric surgery cost?

Bariatric surgery is considered an expensive procedure, due to the expense of the chosen technique, the professionals involved and the selected medical clinic. In general, the value is usually between 20 thousand to 40 thousand reais.

However, this value does not include possible exams and additional consultations, which can be requested from the patient before and after surgery.