50 THE CHINA STUDYAt this point in our lawn analogy, the grass seeds have been put in
the soil and are ready to germinate. Initiation is complete. The second
growth stage is called promotion. Like seeds ready to sprout blades of
grass and turn into a green lawn, our newly formed cancer-prone cells
are ready to grow and multiply until they become a visibly detectable
cancer. This stage occurs over a far longer period of time than initiation,
often many years for humans. It is when the newly initiated cluster mul-
tiplies and grows into larger and larger masses and a clinically visible
tumor is formed.
But just like seeds in the soil, the initial cancer cells will not grow and
multiply unless the right conditions are met. The seeds in the soil, for
example, need a healthy amount of water, sunlight and other nutrients
before they make a full lawn. If any of these factors are denied or are
missing, the seeds will not grow. If any of these factors are missing after
growth starts, the new seedlings will become dormant, while awaiting
further supply of the missing factors. This is one of the most profound
features of promotion. Promotion is reversible, depending on whether the
early cancer growth is given the right conditions in which to grow. This is
where certain dietary factors become so important. These dietary fac-
tors, called promoters, feed cancer growth. Other dietary factors, called
anti-promoters, slow cancer growth. Cancer growth flourishes when
there are more promoters than anti-promoters; when anti-promoters
prevail cancer growth slows or stops. It is a push-pull process. The pro-
found importance of this reversibility cannot be overemphasized.
The third phase, progression, begins when a bunch of advanced cancer
cells progress in their growth until they have done their final damage. It
is like the fully-grown lawn invading everything around it: the garden,
driveway and sidewalk. Similarly, a developing cancer tumor may wander
away from its initial site in the body and invade neighboring or distant
tissues. When the cancer takes on these deadly properties, it is considered
malignant. When it actually breaks away from its initial home and wan-
ders, it is metastasizing. This final stage of cancer results in death.
At the start of our research, the stages of cancer formation were
known only in vague outline. But we knew enough about these stages
of cancer to be able to structure our research more intelligently. We had
no shortage of questions. Could we confirm the findings from India that
a low-protein diet represses tumor formation? More importantly, why
does protein affect the cancer process? What are the mechanisms; that
is, how does protein work? With plenty of questions to be answered, we