From "Introduction to Food Enzymes for Health and Longevity" by Victoras Kulvinskas:
"Most people do not seem to have a large variance of vitamins and minerals over the years. However, as the enzyme levels drop significantly and the enzymes get fewer, old age symptoms manifest. At the world famous Michael Reese Hospital in Chicago, researchers found that old people have only one-thirtieth as much enzymes in the saliva as young folks.
Also people with high enzyme diets have extensive longevity patterns. For example, people like Georgians, Equadorans, and Hunzas have a diet rich in enzymes and have a high concentration of centenarians. They make extensive use of fermentation- soy, dairy, vegetables and fruits.
Also, they utilize sprouting as well as soaking of seeds, which increases the enzyme level up to twenty times, and raw or undercooked food. They also fast seasonally during periods of food scarcity...during fasting there is a halt in digestive enzyme production. The enzymes are used to digest the partially digested stored food of fatty tissue, scars, arthritis, tumors, hardening of the arteries, etc. Thus, the enforced fast is another health and longevity promoting benefit."