HOW DIGESTIVE ENZYMES WORK

The gastrointestinal tract is a dynamic environment with many factors influencing the symphony of activities which influences the efficient digestion of food which is eaten. One important trait is the high variability of pH levels food encounters as it passes through the alimentary canal.

When food is immediately ingested it encounters saliva in the mouth. The normal average salivary pH is 6.7 with a normal range from 6.2 – 7.6.¹ The next step along the digestive tract is through the esophagus and into the stomach. Gastric pH is strongly acidic at a pH level of 1.0-2.5. While counterintuitive to some, this level of acidity is essential in the efficient digestion of proteins and other macronutrients. Moving on the food, now considered chyme, progresses into the duodenum of the small intestine where it encounters a significant shift in the pH level. The average pH in healthy humans for the proximal small intestine is 6.4 and slowly progresses towards an average level of 7.5 in the terminal ileum as things progress through the small intestine. There is yet another pH drop with passage through the ileocecal valve into the proximal colon, which slowly changes to about pH of 7.0 by the time the distal areas are reached.²

The story of fluctuating pH is incredibly important when looking at the best strategies for supplementing with digestive enzymes. Enzymes are a key component indigestion. The challenge is that enzymes need the proper pH environment to be active and provide the claimed benefits. This proper pH environment is unfortunately not the case for most people. While our focus is not on why pH drift in the digestive tracts occur, it is important to understand that this occurs for a variety of reasons as humans age and it can impact the appropriate digestion of a whole host of nutrients.³ With this understanding of age-related declines, choosing enzymes which remain active through a broad range of both acidic and alkaline conditions is a key component to the optimization of digestion and ultimately the restoration of gastrointestinal health.* It is also important to consider the acidic environment within the stomach. While even at its highest pH levels the environment is still extraordinarily harsh and strongly acidic. This necessitates that the digestive enzyme of choice not only is active in a broad range of pH, but is also stable in the lowest pH environments. If this isn’t the case, then when the enzymes finally make it to the proximal small intestine where they can put their digestive superpowers to work, they will have been affected by the acid environment of the stomach in such a way that they can no longer help to optimize the digestive process.* In summary, a couple factors which are key in the selection of a digestion enzyme include:

• Enzymes which are active over a broad range of both acidic and alkaline pH
• Enzymes which are stable in a highly acidic environment, so they remain active following transit through the stomach.