NCSF Sport Nutrition Specialist Certification (SNS) Practice Test

Orlistat primarily works by blocking fat absorption in the gastrointestinal tract. This medication inhibits the action of pancreatic lipase, an enzyme responsible for breaking down dietary fats into smaller molecules so they can be absorbed by the intestines. When orlistat is taken, it prevents approximately 25-30% of the fat consumed from being digested and absorbed. This undigested fat is then excreted from the body through feces, which can lead to a reduction in overall calorie intake and weight loss. The other mechanisms mentioned, such as increasing energy expenditure, enhancing carbohydrate metabolism, or promoting protein synthesis, do not accurately describe how orlistat functions. Rather, these processes involve different physiological pathways not directly influenced by orlistat's mechanism of action, making option B the most appropriate answer regarding the drug's primary effect on the body.