The prevalence of obesity has increased dramatically over the last 20 years. Moreover, morbid obese patients routinely suffer from serious medical problems, especially cardiovascular disease. Medical therapy for morbid obesity offers no substantial long-term benefit, and thus the first choice therapy for severe obesity is effectively surgery. Gastrointestinal surgery for obesity, also called bariatric surgery, alters the digestive process by limiting food intake and facilitating malabsorption of nutrients from the diet. This arricie reviews the types and evolution of morbid obesity surgery performed in humans and proposes the pig model as an alternative when practicing new surgical techniques or improving actual procedures, as well as to evaluate the metabolic consequences of these procedures. Based on similarities between humans and pigs in terms of their anatomical, physiological and metabolic characteristics, the pig also provides an opportunity to develop, evaluate specific techniques in open and laparoscopic surgery. Finally, a complete review of macronutrient digestion and absorption between pigs and humans is done in order to justify the use of this model. Therefore, the objective of this arricie was to ¿Illustrate the use of the pig as a model for studying nutrient digestion and absorption in humans who undergo bariatric surgery and to review how, through digestibility trials, a digestion and absorption assessment of nutrients should complement classical human assessments with surgery.