The First Step of Digestion: What Happens When You Bite?

When you take a bite of food, the first thing that happens is that your teeth begin to break down the food into smaller pieces. This process is called mastication. As you chew, the food is moistened with saliva, which helps to break it down further. The saliva also contains enzymes that begin to break down the carbohydrates, proteins, and fats in the food.