Mechanical digestion is one of the processes used to digest food. This aspect of digestion involves mechanics rather than chemistry. Digestion will break down food so that it can be used by the body. This process can occur in the mouth, stomach, or intestines. Digestion allows the nutrition from food and liquids to be absorbed into the body. The process of mechanical digestion typically occurs in the mouth, while chemical digestion occurs in the stomach and intestines.
Mechanical digestion typically refers to the process of chewing, also called mastication. This is done in the mouth. The teeth are used to break down the food into smaller pieces. This will make it easier for the stomach to continue to digest the food using chemical digestion with enzymes. Mechanical digestion through chewing will involve various muscles around the jaw and face, as well as the teeth in the mouth, including incisors and molars. Cutting food into smaller pieces can also be considered a form of mechanical digestion, because it makes food easier to digest. Using a blender or food processor can also prepare food for easy digestion.
Chemical digestion will also begin in the mouth, where chewing occurs. Saliva has enzymes in it that will begin the chemical digestion process. However, saliva is 98% water, so it does not contribute to digestion much. Most of the chemical digestion process occurs in the stomach, where enzymes and hydrochloric acid break down food further. The stomach muscles can also help to break food down in this stage. This is where food will be mostly digested and prepared for absorption.
Digestion then continues in the small intestine. This digestion is mostly chemical, like in the stomach. This is the last process of digestion before nutrients from food can be absorbed. The nutritional absorption process takes place mostly in the large intestine of the body. Digestion, both mechanical and chemical, allows the food to be broken down into nutrients for absorption.