Page 19 - Spring2010

TRYPING UP THE DIET tease inhibitors in soy, and enough heat could
THE PERILS OF PROTEASE INHIBITORS dispatch all of them, the obvious solution would
Protease inhibitors inhibit some of the key seem to be to cook the soybeans to death. Unfor-
enzymes that help us digest protein. The best tunately, extra heating damages the structure of
known of these protease enzymes is trypsin. the essential amino acids methionine and lysine
Most of the USDA studies performed over the and in extreme cases damages the total protein
years have looked at trypsin inhibitors in soy- so much that it is hard to digest, assimilate and
beans, but these anti-nutrients are also found in utilize by the body. When modern food manufac-
other beans, grains, nuts, seeds, vegetables of turers use alkaline solutions to speed things up,
the nightshade family (potatoes, tomatoes and the essential amino acid lysine can be turned into
eggplant) and various fruits and vegetables. the toxic lysinoalanine. 13-15 Even if food manu-
Traditionally, few of these foods caused facturers made it a priority to cook soybeans just
health problems be- right, some protease
cause they were rarely inhibitors would be
eaten every day and undercooked and
because cooking de- others overcooked.
activates most of the Despite scores of
protease inhibitors. USDA studies, no
But given the grow- practical method of
ing tendency to fill solving this prob-
up on plant foods, lem has ever been
and the fashionability devised. To this day,
of al dente cooking the only way to solve
and “live food” (raw) the protease inhibi-
vegan diets, more and tor problem is old- Proponents of
more people are eat- The carnivorous piranha plant fashioned fermenta- plant-based
ing foods with their shows that plants can bite back! tion. diets generally
protease inhibitor Many people
content intact. Proponents of plant-based diets dismiss the protease inhibitor conundrum, say- believe their
generally believe their diets provide plenty of ing that a few of them here and there don’t pose diets provide
protein, but this premise fails to take into account a problem. That is undoubtedly true for people plenty of
the fact that protein swallowed is not the same as eating a richly varied omnivorous diet. But for
protein digested when protease inhibitors are in soy formula-fed infants, vegetarians and others protein, but
the picture. Without high-quality, usable protein, who eat soy every day, the numbers add up. this premise

growth, repair, immunity, hormone formation Even the small quantities used as extenders in fails to take
and all metabolic processes will suffer. meat products, canned tuna, bakery goods and
The protease inhibitors in soybeans are not other ordinary supermarket and health food store into account
only more numerous than those found in other products and fast foods can adversely affect the fact that
beans and foods, but more resistant to neutral- people whose digestive capacities are already protein
ization by cooking and processing. Only the compromised by low hydrochloric acid levels,
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old-fashioned fermentation techniques used to pancreatic insufficiency, bowel diseases, gluten swallowed is
make miso, tempeh and natto come close to intolerance and other health challenges. Worse, not the same
deactivating all of them. With all other cooking the average American may be eating soy protein as protein
processes, some trypsin inhibitors remain. The along with soy or corn oils, a deadly combination
levels of active protease inhibitors remaining in that has led to pancreatic cell proliferation and digested
modern soy products vary widely from batch to cancer in laboratory rats. Both these oils have when
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batch, and investigators have found startlingly been shown to initiate or fuel cancers, and be- protease
high levels in some soy formulas and soy protein cause of a synergistic effect, the danger appears
concentrates. 6-12 to be greatest when the combined intake is high. inhibitors are
Given the fact that heat deactivates the pro- Soy protein, soy oil and corn oil are all familiar in the picture.

SPRING 2010 Wise Traditions 19