Abstract
Obesity is a disease with a rapidly increasing prevalence all over the world in recent years. Genetic and environmental factors are involved in the etiology of obesity, and the effect of microbiota on obesity is becoming increasingly clear. Obesity treatment has various treatment modalities such as behavior modification, medical nutrition therapy, physical activity enhancement, and surgical intervention. When other treatment methods are not successful, bariatric surgery is usually resorted to as the treatment method. Some changes such as food choices, the level of hormones and enzymes due to anatomical changes, pH of the stomach, and microbiota are observed after bariatric surgery. Alteration in the microbiota composition after bariatric surgery has also been reported to be important in achieving body weight loss and preserving body weight loss.