Below is an excerpt from the following link:
http://www.living-foods.com/articles/enzymes.html

"HOWELL: It seems that we inherit a certain enzyme
potential at birth.

This limited supply of activity factors or life force
must last us a lifetime. It's just as if you inhented
a certain amount of money. If the movement is all one
way -- all spending and no income -- you will run out
of money.

Likewise, the faster you use up your supply of enzyme
activity, the quicker you will run out. Experiments at
various universities have shown that, regardless of
the species, the faster the metabolic rate, the
shorter the lifespan.

Other things being equal, you live as long as your
body has enzyme activity factors to make enzymes from.
When it gets to the point that you can't make certain
enzymes, then your life ends.

HDN: Do people do anything which causes them to waste
their limited enzyme supply?

HOWELL: Yes. Just about every single person eats a
diet of mainly cooked foods. Keep in mind that
whenever a food is boiled at 212 degrees, the enzymes
in it are 100% destroyed.

If enzymes were in the food we eat, they would do some
or even a considerable part of the work of digestion
by themselves. However, when you eat cooked,
enzyme-free food, this forces the body itself to make
the enzymes needed for digestion. This depletes the
body's limited enzyme capacity.

HDN: How serious is this strain on our enzyme "bank"
caused by diets of mostly cooked food?

HOWELL: I believe it's one of the paramount causes of
premature aging and early death. I also believe it's
the underlying cause of almost all degenerative
disease."

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Joe Zychik