How Are Digestive Enzyme Inhibitors Used to Treat Obesity?

Obesity is the abnormal or excessive accumulation of fat to the point of posing a health risk to the individual. The National Institute of Health uses the body mass index (BMI), which measures a person's body fat against his or her height and weight, as a standard measure of obesity and healthy weight. Here are the BMI categories:

* Underweight = less than 18.5
* Normal weight = 18.5 to 24.9
* Overweight = 25 to 29.9
* Obesity = 30 or greater

Obesity is caused by various factors, including excessive intake of food and inadequate exercise. Hereditary factors have also been blamed for the condition. While the basic tenet of eating less and moving more is recommended in the management of obesity, other treatment methods are employed, including barriatic surgery, low-calorie diets, appetite suppressants and, of course, the use of enzyme inhibitors.

Digestive Enzymes

• Digestive enzymes are naturally occurring proteins found in the digestive system that help speed up the chemical reactions involved in the breakdown and absorption of food. They are produced by glands in various parts of the digestive system extending from the mouth to the large intestine. For example, the salivary glands produce salivary amylase, an enzyme that breaks down starch into sugars; the gastric glands produce pepsin, which breaks down proteins into peptides; and the pancreas produces pancreatic lipase, which breaks down fats into fatty acids and glycerol. There are several other digestive enzymes secreted by other parts of the digestive system, including the stomach, small intestine, pancreas and liver.

Digestive Enzyme Inhibitors and How They Work

• Digestive enzyme inhibitors prevent the normal action of digestive enzymes, the idea being if the food is not broken down, it is not absorbed and therefore not stored in the body as fat. Enzyme inhibitors work by interfering with the enzyme action by binding to the surface of the enzyme thereby preventing the substrate or substance to be broken down from binding to the enzyme. Most drugs are designed this way and digestive enzyme inhibitors used in the treatment of obesity are no exception. One such drug is Orlistat, marketed with the brand name Xenical in the U.S. It is a lipase inhibitor and therefore prevents the digestion and absorption of fats, directing them out of the body through bowel movements instead.