Digestive Enzymes

Overview

Digestive enzymes are a group of enzymes that break down polymeric macromolecules into their smaller building blocks, in order to facilitate their absorption by the body. Digestive enzymes are found in the digestive tracts of animals (including humans) and in the traps of carnivorous plants, where they aid in the digestion of food, as well as inside cells, especially in their lysosomes, where they function to maintain cellular survival.

Types of Digestive Enzymes

There are three main types of digestive enzymes, each with a specific function in the digestive process:

Proteases and Peptidases

Proteases and peptidases break down proteins into their building blocks, amino acids. They are produced in the stomach and pancreas.

Lipases

Lipases break down fat into three fatty acids and a glycerol molecule. They are produced in the pancreas.

Amylases

Amylases break down carbohydrates such as starch into simple sugars. They are produced in the salivary glands and pancreas.

Function of Digestive Enzymes

Digestive enzymes play a key role in breaking down the food we eat into nutrients that can be absorbed by the body. They are secreted by different parts of the digestive system, including the salivary glands, stomach, pancreas, and small intestine. These enzymes then mix with food in the stomach and small intestine to start the process of digestion.

Role in the Stomach

In the stomach, the action of digestive enzymes begins. Here, the enzyme pepsin plays an important role in the digestion of proteins. Pepsin is the active form of the enzyme pepsinogen, which is released into the stomach and mixed with stomach acid to activate it.

Role in the Small Intestine

The small intestine is the major site of digestion and absorption of nutrients. Here, several enzymes from the pancreatic juice and the lining of the intestine carry out the breakdown of large molecules of protein, carbohydrates and fats into smaller molecules that can be absorbed.

Digestive Enzyme Disorders

Digestive enzyme disorders occur when the body is unable to produce enough digestive enzymes to break down and absorb nutrients from food. There are many different types of digestive enzyme disorders, such as lactose intolerance, celiac disease, and pancreatic insufficiency.

Lactose Intolerance

Lactose intolerance is a common digestive disorder where the body is unable to fully digest lactose, a sugar found in milk and dairy products.

Celiac Disease

Celiac disease is an autoimmune disorder where the ingestion of gluten leads to damage in the small intestine. People with celiac disease cannot absorb nutrients properly due to the damage to the villi in the small intestine.

Pancreatic Insufficiency

Pancreatic insufficiency is a condition where the pancreas does not produce enough digestive enzymes. This can lead to malnutrition and weight loss.