186 THE CHINA STUDYIMMUNITY FROM OURSELVES
Even though this system is a wonder of nature when it is defending the
body against foreign proteins, it is also capable of attacking the same
tissues that it is designed to protect. This self-destructive process is
common to all autoimmune diseases. It is as if the body were to commit
suicide.
One of the fundamental mechanisms for this self-destructive behav-
ior is called molecular mimicry. It so happens that some of the foreign
invaders that our soldier cells seek out to destroy look the same as our
own cells. The immune system "molds" that fit these invaders also fit
our own cells. The immune system then destroys, under some circum-
stances, everything that fits the mold, including our own cells. This is
an extremely complex self-destructive process involving many different
strategies on the part of the immune system, all of which share the same
fatal flaw of not being able to distinguish "foreign" invader proteins
from the proteins of our own body.
What does all of this have to do with what we eat? It so happens that
the antigens that trick our bodies into attacking our own cells may be
in food. During the process of digestion, for example, some proteins
slip into our bloodstream from the intestine without being fully broken
down into their amino acid parts. The remnants of undigested proteins
are treated as foreign invaders by our immune system, which sets about
making molds to destroy them and sets into motion the self-destructive
autoimmune process.
One of the foods that supply many of the foreign proteins that mimic
our own body proteins is cow's milk. Most of the time, our immune
system is quite smart. Just like an army arranges for safeguards against
friendly fire, the immune system has safeguards to stop itself from at-
tacking the body it's supposed to protect. Even though an invading
antigen looks just like one of the cells in our own body, the system can
still distinguish our own cells from the invading antigen. In fact, the im-
mune system may use our own cells to practice making molds against
the invader antigen without actually destroying the friendly cell.
This is analogous to training camps in preparations for war. When our
immune system is working properly, we can use the cells in our body that
look like the antigens as a training exercise, without destroying them, to
prepare our soldier cells to repulse the invading antigens. It is one more
examplel of the exceptional elegance of nature's ability to regulate itself.