Protein Digestion

You know that digestion is the process of breaking down food, including proteins, into molecules that are small enough to be absorbed by your body's cells. Digestion can be mechanical or chemical. Chewing your food is mechanical digestion and mixing food with saliva in your mouth starts the process of chemical digestion. 

Digestion of carbohydrates begins in the mouth, with chewing and saliva. However, protein digestion does not begin in the mouth. Rather, it starts in the stomach--first with hydrochloric acid, then with enzymes. The chemicals in your stomach disassemble amino acids from the foods you have eaten and form new proteins that your body needs. Most foods are a mix of carbohydrate, fat, and protein molecules. Carbohydrates, fats, and proteins--plus vitamins and minerals--are nutrients. Recall that nutrients provide energy and everything else you need to grow, move, think, make repairs, maintain your systems, and fight disease.

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