Digestive enzyme therapy can be an important first step in restoring health by remedying digestive problems. The human body makes approximately 22 digestive enzymes, capable of digesting protein, carbohydrates, sugars and fats. People digest food in stages: beginning in the mouth, moving to the stomach, and finally through the small intestine. At each step, specific enzymes break down different types of food. An enzyme designed to digest protein, for example, has no effect on carbohydrates, and an enzyme active in the mouth will not be active in the stomach. Each site along the digestive track has a different degree of acidity that allows certain enzymes to function while inhibiting others.