Bariatric surgery is the general name given to various bariatric surgery operations that aid in weight loss.Obesity is one of the biggest health problems seen worldwide, especially in western societies. In many scientific studies, obesity has been shown as the most important cause of many diseases that increase mortalitymorbidity. The most widely used measurement method for obesity is BMI (body mass index). It is the value obtained by dividing the weight by the square of the height.18.5-24.9 kg / m2 Normal individuals25-29.9 kg / m2 overweight30-40 kg / m2 <Obese40 kg / m2 <Morbidly obeseHowever, an increase in Body Mass Index (BMI) may not always mean obesity. Body mass index may be high in people with high muscle tissue. Expert judgment is important to understand the source of the gains in body weight. Obesity should be considered if the waist circumference is 102 cm in men88 cmmore in women.The main purpose of performing obesity surgery is to prevent the development of diseases caused by obesity (DM, cardiovascular diseases, sleep apnea syndrome, etc.) as well as weight loss. Diseases if they occur is to treat.Alonea combination of many factors can cause obesity. These are genetic predisposition, endocrinemetabolic diseases, socialcultural differences. Basically, the amount of energy entering the body more than the amount burned causes obesity.It is estimated that around 1.7 billion people worldwide are overweight individuals. The situation is more serious in the USA. About 2/3 of the population is overweightabout half of them are classified as obese.Obesity surgery has been performed widely in the world in recent years. The first effective obesity surgery was performed in the United States in 1954 by KremenLinner (jejunaileal bypass).The operations are divided into 3 according to the mechanism of action.Restrictive surgery (adjustable gastric banding, sleeve gastrectomy)Surgeries that disrupt absorption (Roux-en-Y gastric bypass, mini gastric bypass)Combined surgeries that restrictdisrupt absorption (duodenal switch, SADI-S)Who Can Have Bariatric Surgery?Certain conditions are required for bariatric surgery to be performed.- Body mass index (BMI) should be above 40 (according to some sources, 35).- In the presence of uncontrolled diabetes, hypertensionhyperlipidemia, this rate can be lowered.- There should be no serious comorbidities.-The person should be in good mental health.