The Gastric Bypass is indicated for people who are seriously overweight and who have tried for years to lose weight through weight loss treatments or conventional diet treatments.

Gastric bypass or gastric diversion surgery is a technique that is performed by laparoscopic surgery, that is to say, unopened, which consists of reducing the volume of the stomach and making a "short circuit" system in the bowels so that part of the food is not absorbed.

If you are interested in the gastric bypass but have doubts, you can request your first free appointment, by video conference, from your place of residence at our clinic in Madrid.

gastric bypass



Gastric Bypass

Surgery Duration

Surgery Duration

3 hours.

Admission Time

Admission Time

72 hours.

Type of Anaesthesia

Type of Anaesthesia


Type of Surgery

Type of Surgery


Recovery Time

Recovery Time

10/12 days.


Bypass Promotion for a limited time, before 12.000 €

10.900 €

This price includes:

Preoperative tests

Preoperative evaluation

Surgery and Admission

Follow up

Nutritional Monitoring

Follow-up of bariatric surgery with Psychology (includes 2 consultations)

And if necessary in follow-up:

Endoscopic Evaluation

Analytical Evaluation

Eco-graphic Evaluation

The gastric bypass is a technique that has clearly proven to be effective for the treatment of obesity throughout its more than 25-year history.

It is a mixed surgical intervention since it is based on food restriction but also on malabsorption (preventing food and its nutrients from being absorbed and assimilated by the small intestine).

In a recent survey by the International Federation for Surgical Obesity (IFSO) of which Dr. Jesús Lago Oliver is a member, the gastric bypass was the most widely used technique by American surgeons to treat obesity because of its great effectiveness in long-term weight control.

This surgery generates an anatomical modification of the digestive system allowing the definitive and successful treatment of obesity, that by means of the laparoscopic gastric bypass technique leaves only a small stomach that is directly connected to the small intestine.

Thanks to this, food does not pass through much of the small intestine, so the absorption of calories and nutrients is greatly diminished.

By reducing the volume of the stomach, the gastric bypass causes early satiety, thus reducing the volume of food ingested.

On the other hand, the gastric bypass reinforces this reduction in the amount of food ingested by means of an intestinal "short circuit" so that part of the food is eliminated in the faeces without being absorbed.

These two mechanisms make the gastric bypass one of the most effective methods, that is why American surgeons choose it as the standard technique in most patients.

The greatest weight loss will occur during the first year but then it will continue to be lost for even five years but at a slower rate.

Despite the possible complications, you should know that gastric bypass has many more benefits than risks. Compared to other bariatric surgery interventions, the bypass involves fewer risks and that is why it is the most widely used technique for this type of case.

Gastric bypass is indicated and can therefore be done in people who have a body mass index greater than 40 (remember that the Body Mass Index is calculated by dividing weight by height squared) or in people with a body mass index greater than 35 but with risk factors associated with obesity such as diabetes and hypertension.

Gastric bypass surgery is performed by laparoscopy (unopened) so recovery is very fast and virtually painless.

The operation lasts from 2 to 4 hours and recovery takes place in 2-3 days.

After the intervention, a postoperative diet is performed for one month, in which we basically manage the consistencies of the food.

From the sixth week onwards, the normal diet can usually be introduced.

Your ideal weight

The IMC/BMI is used to classify the state of the person, and is calculated from the formula: weight (kg) / height (m2). This is a common calculation for both men and women. Remember that this nutritional index only applies to adults.

  • IMC/BMI is less than 18.5, it corresponds to "underweight."
  • IMC/BMI between 18.5 and 24.9, "normal" or healthy weight value.
  • IMC/BMI is between 25.0 and 29.9, it corresponds to “overweight”.
  • IMC/BMI is 30.0 or higher, it corresponds to “obesity”.
  • To calculate your IMC/BMI, see the IMC/BMI Calculator.
Last update / January 8, 2024
Clínica Fuensanta
Miembro SECE
Centro autorizado por la Comunidad de Madrid
Miembro SECO
Miembro SEEDO
AE Cirujanos
World Professional Association for Transgender Health
Sociedad Española de Directivos de la Salud
International Federation for the Surgery of Obesity
European College of Aesthetic Medicine & Surgery