Introduction
Your body requires the regular consumption of food to obtain the nutrients it needs to function. However, before the food you eat can be absorbed and used by your body, it must be broken down into its most basic parts. To do this, the body secretes special digestive enzymes that help break down the carbohydrates, proteins and fats into usable sources of energy and nutrition.
Mouth
Your food's first contact with digestive enzymes occurs in the mouth. Even before you place food in your mouth, the salivary glands respond to food stimulus (such as sight or smell) by producing saliva. Contained in the saliva is the enzyme amylase. Assisted by chewing, amylase works to break down carbohydrates into smaller particles of dextrin and maltose.
Stomach
After your food is swallowed, muscles push it down the esophagus and into the stomach, where the food meets a new set of digestive enzymes. Glands within the stomach lining produce gastric acid and pepsinogen. The hydrochloric acid (HCl) in the gastric juices then mixes with the pepsinogen to create the enzyme pepsin. Pepsin is an important digestive enzyme, because it breaks down the amino acid bonds of the proteins so they can be absorbed by the body.
Small Intestine
Once the stomach has completed its digestive duties, your food is dumped into the small intestine. By this point, only the carbohydrates and proteins have been partially broken down, leaving the fats. This is where the pancreatic enzyme lipase comes into play. Lipase breaks down the fats in your food into fatty acids and glycerol, which can then be absorbed into the body and used for functions such as creating energy. The pancreatic enzymes also further break down the proteins and carbohydrates, using the enzymes trypsin for the proteins and pancreatic amylase for the carbohydrates. The remaining substance from your digested food then enters the large intestine. Here much of the water and remaining sodium is removed, leaving waste behind that can be expelled from the body in the form of feces.
