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by Dr. Joyce Luteyn
Vital FUNCTIONS
of Digestive Enzymes
Enzymes, mostly proteins, have some involvement in every metabolic
activity in the body—from digesting and assimilating food to catalyzing
the thousands of reactions that are necessary for the body to function. Enzymes
are involved in the synthesis and repair of DNA; in the production of proteins, fats, and connective tissue necessary to grow and regenerate cells; and in the breakdown and detoxification of cellular wastes that are the by-product of normal metabolism.
Humans and animals are capable
of making most of their own metabolic
enzymes as long as the nine essential amino
acids are available in adequate amounts in
the diet. The other amino acids necessary to
produce all proteins and most enzymes can
also be synthesized by the body, although
the amount and types vary from species to
species (reflecting the specificity of their
dietary niche) and even from individual to
individual (reflecting the actual content and
variety of their diet).
Unfortunately, the cellular machinery that
drives all this production of amino acids,
proteins, and, therefore, most enzymes
tends to wane with age, cellular damage,
and dietary deficiencies, leading to depletion
of the total body supply and frequently
contributing to poor health.
Although the body produces and needs
hundreds of enzymes, most of the energy
expended by the body goes toward the production
of digestive enzymes, since food
is the ultimate fuel source for all metabolic
activities.
Most people know a bit about digestive
enzymes, even if from their middle school
biology class. What they learn mostly is about
the body’s digestive enzymes and where, if not
how, they work. To review, we will follow a food
particle through its usual route.
When food is put in the mouth, amylase
is released in the saliva to start the breakdown
of starches as the food is chewed.
unfortunately, most people today eat too
quickly for that source of amylase to do us
much good. Next, as the food enters the
stomach, pepsin, a protease, kicks in to
partially break up proteins into peptides
(groups of amino acids). Other proteases,
such as trypsin and chymotrypsin, are also
secreted by the pancreas where the proteins
are further broken down. Each of these proteases
works on a different part of the protein
molecule. They are additive in function, not
redundant. Pepsin requires the very acid pH
of the stomach to work. The common use of
antacids and acid suppressing medications,
as well as the natural reduction in stomach
acid associated with aging, may render these
naturally occurring enzymes less or even
ineffective. This leaves the remaining job of
protein digestion disproportionately to the
pancreas and small intestine, which frankly
had counted on their buddy the stomach to
keep up its end of the job.
The pancreas also produces amylase
to further break down starch and lipase
to break down fats. Lipase works in conjunction
with bile produced by the liver to
emulsify and break down fat molecules into
particles small enough for the small intestine
to absorb and use to feed your body.
The small intestine also absorbs the broken
down starches sugars and proteins after the
work of enzymes is complete. By the time
the food has reached your large intestine,
the process of nutrient absorption is largely
but not completely finished. There occurs
the removal of excess fluid from the waste,
the processing of undigested foods, and the
bacterial breakdown of waste.
What is missing from this cooperative
story above is how inherently inefficient
the system is. If we rely only on it to keep
the machinery moving, the machine will be
stressed, the product will be inadequate,
and the possible effects on the body are
intestinal discomfort, bowel changes, poor
nutrition, and premature aging of the body’s
repair mechanisms.
Why this inefficiency in what seems like a
well designed system? Because the system
was never designed, so to speak, to be all
enzymes to all foods. Humans and animals
possess largely specialized digestive tracts
to reflect their respective diets. Herbivores,
such as cattle and deer, produce cellulase to
help break down the plant cells that make
up their diet. The raw grasses, plants, fruits,
and grains that they eat are loaded with just
the digestive enzymes that are needed to
process that food itself. If cattle were fed
only cooked grain, they would die (which is
why the feedlots are the last stop for them),
although digestive enzymes are added as a
supplement to their food, partially to control
their contribution to greenhouse gases.
Carnivores eat not only meat but also
the vegetable filled guts of their prey, thus
deriving live digestive enzymes from their
meals, even if they don’t graze themselves.
Because they eat their prey raw, these
enzymes remain active and are a vital part of
their nutrition. Anyone with a cat can attest
to their affinity for eating grass and plants.
They crave it because they need it.
Omnivores, like humans, eat a diet of
variety and opportunity. If it can be hunted,
caught, grown, picked, dug up, cultured, or
fermented, we humans eat it, as do most
other omnivores that thrive in our environment
—on a variety of foods, including our
leftovers. We are the only animals to eat
such a high proportion of our food cooked.
Cooking foods, especially meats, initially
was a huge boon to survival of our species,
as it allowed for better assimilation of some
nutrients, especially proteins and calories,
and helped break down the indigestible
cell wall of plants to allow access to their
nutrients.
As long as the human diet included
plenty of raw and whole food as well, the
balance of ingested plant based digestive
enzymes to metabolic enzymes allowed
the body to assimilate these nutrients well.
Today, however, many of us eat an excess of
cooked, processed foods that are devoid of
active enzymes, and a paucity of foods high
in natural enzyme activity.
The “life force” of raw food enzymes is
what allows a fresh bean to sprout or a green
tomato to ripen. Cook, freeze or pickle a
bean or tomato and they will never ripen,
even though the contents of that bean or
tomato remain otherwise intact. That life
force depends on the enzymes retaining their
unique three-dimensional shape, such as a
key requires a very specific shape to fit into a
specific lock. In order to preserve that unique
shape, enzymes must be extracted whole
and intact, in their functional state. Ironically,
the heavy nutrient load of cooked food when
offered to the body devoid of the enzymes
that food in its raw state would provide, can
lead exactly to the nutrient absorption problems
that cooking initially addressed.
The body compensates by producing
more endogenous enzymes. In the face of
decreased absorption of the nutrients, it
needs to produce them, thus depleting the
entire body store of enzymes and enzyme
precursors.
Even in a modern diet relatively rich in
raw foods, unless these foods are very fresh
and untreated, beneficial enzymes may be
largely inactivated or in many instances
contain a very narrow spectrum of active
enzymes. Short of eating organic produce
from your own garden (and chomping on
some wild berries and grasses while you
are at it), taking supplemental plant-based
digestive enzymes is the only reliable way
to insure adequate intake of enzymes to
protect the balance between your digestive
and metabolic needs and the raw materials
needed to provide them.
unlike vitamins and minerals, enzymes
cannot be produced chemically. Because
the function of enzymes is dependent on
their natural three dimensional conformation
(and this is easily destroyed by heat or
chemicals), they must be extracted whole,
either from living plants or, in most pharmaceutical
products, from the organs of
slaughtered animals.
Unlike supplemental enzymes of animal
origin, plant-based enzymes, including
those discussed above and especially those
found in broad-spectrum supplements,
work over a broad pH range. This allows
them to aid in predigestion and digestion
in the stomach, and to continue aiding in
digestion throughout the digestive tract,
thus easing the stress on the body’s own
enzyme pool and, more importantly,
allowing the full extraction of nutrients from
the foods we eat.
Digestive plant enzymes are unique in
that they not only overlap in function with
the body’s own metabolic enzymes but provide
many enzymes the body cannot make
in sufficient quantities or at all.
Lactase, the enzyme most familiar to
us, is absent in all but a small number of
adults. Indeed, the lactase that infants and
children produce to digest mother’s milk is
produced by entirely different cells than that
produced by adults, and, in most people, it
wanes by adolescence. Lactose intolerance,
especially to cow’s milk, is very common,
especially in non-caucasians. Cellulase,
xylase and xylanase help break down otherwise
indigestible components of plant fiber,
allowing maximum extraction of nutrients.
Alpha-galactosidase aids in the digestion
of the complex sugars found in beans and
cruciferous vegetables such as broccoli and
cauliflower. These foods, which can otherwise
cause excessive bloating and flatulence,
are better digested in the presence of
this supplemental enzyme, which humans
cannot produce.
Although some of my patients, because
of pancreatic problems, require animal
based digestive enzymes, this is relatively
rare. What are not rare however are digestive
diseases of every other stripe, and for these I
frequently recommend a good quality plantbased
digestive enzyme.
With so many choices available to the
consumer today, selecting a product that
is right for you can be confusing. Although
many good products are available, I look for
and recommend blends that provide a full
spectrum of digestive enzymes along with
certain botanicals that may have synergistic
beneficial effects on digestion and metabolism.
The product should contain specific
enzymes to assist in the breakdown of proteins,
fats, carbohydrates, grains, fiber, nuts,
seeds, soy, legumes, fruits, vegetables, and
all components of dairy products. Given the
rapid globalization of our society, and with
it our increasing exposure to foods novel to
our systems (imagine the first time a Native
Alaskan ate tofu), a digestive enzyme supplement
lacking in any of these compliments is
inadequate.
In addition, I recommend a product
that includes traditional botanicals such as
ginger root, turmeric, naringin, aloe vera,
and cat’s claw for their soothing effect on
the digestive tract. The product I recommend
also contains barley, oat and wheat
grasses as powerful sources of nutrition and
beneficial fiber.
The proper way to take a digestive enzyme
supplement is to swallow one at the beginning
of a full meal and an additional one
during or at the finish of the meal to ensure
that food and enzymes travel together. For a
snack or smaller meal, one capsule may suffice. Occasional indigestion between meals
may be relieved by one capsule taken with
a glass of water.
Immediate benefits of this therapy should
include reduction in dyspepsia and intestinal
distress. Long-term benefits, which
may be more subtle, include improved
nutritional status and an overall reduction
in stress on the body’s metabolic systems.
Digestive enzymes have also been shown to
have anti-inflammatory properties, not only
on the bowel but also in the blood stream,
although the mechanism is not well understood.
As with any medication or supplement,
there are people who should not take these
products. Anyone who is pregnant, nursing
or on prescription medications for diabetes
or hypertension should consult first with a
physician knowledgeable about their condition
and supplemental plant enzymes. The
latter may be harder to find, but not impossible,
as many of my colleagues as well as
myself are embracing nutritional supplements
as a complement to our traditional
allopathic practice.
For more information on digestive
enzymes call 1.800.574.1961 or visit www.mtcapra.com.
Joyce Luteyn, M.D., is a boardcertified family practitioner. She received her medical degree from the university of Washington, and completed a UW affiliated family medicine residency in Vancouver, Washington, in 1997. She has been in fulltime practice for eight years in Olympia, where she lives with her husband and two children. Her practice encompasses the full range of primary care for patients of all ages.
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