Digestion in the Stomach




There is a common misconception that enzymes are destroyed by stomach acid. Nothing could be further from the truth. Stomach acid does not digest protein. Rather, it activates an enzyme called pepsinogen, which then becomes pepsin that is secreted by the stomach wall. This enzymes is only active within the pH range of 3.0 to 5.0 and requires the acid to maintain that pH. Pepsin is very specific in its action and is simply incapable of digesting food enzymes, which are very large molecules and are more that just protein.


The pH within the stomach rarely, if ever, drops below 3.0. Pure stomach acid has a pH of 1.8 when it first enters the stomach, but is quickly diluted in the presence of food. Regardless, the highly acidic environment of the stomach does not destroy plant enzymes. They simply become dormant until reaching the higher pH levels in the small intestine, where they again become active and continue the digestive process. Once their digestive function in the gastrointestinal tract is completed, a large number of enzymes are absorbed through the gut wall into the blood stream.

A lot of research remains to be done to determine the exact fate of these enzymes after they pass through the gut wall into the blood. However, it is known that plant enzymes will pass from the body into the urine after they have completely lost their usefulness.