Where is the breakdown of carbohydrates in the human body?

In the human body, the breakdown of carbohydrates begins in the mouth.

The salivary glands together with saliva secrete a special enzyme – amylase. It breaks down the starch molecule, which is a polysaccharide made up of many glucose residues, into simpler oligosaccharides. They taste sweet.

A simple experiment can be done to ensure that carbohydrates are actually broken down in the mouth. Take a slice of bread in your mouth and keep it there until you feel a sweetish taste. This means that the starch contained in the flour has begun to break down.