Authors: T. Colin Campbell,Thomas M. Campbell
104 THE CHINA STUDY
CIRCLING BACK
In the beginning of my career, I concentrated on the biochemical pro-
cesses of liver cancer. Chapter three delineates the decades-long labo-
r a t o r y work we did with experimental animals, work that passed the
requirements to be called "good science." The finding: casein, and very
likely all animal proteins, may be the most relevant cancer-causing sub-
stances that we consume. Adjusting the amount of dietary casein has
the power to turn on and turn off cancer growth, and to override the
cancer-producing effects of aflatoxin, a very potent Class IA carcinogen,
but even though these findings were substantially confirmed, they still
applied to experimental animals.
It was therefore with great anticipation that I looked to the China
Study for evidence on the causes of liver cancer in humans. 62
Liver cancer rates are very high in rural China, exceptionally high in
some areas. Why was this? The primary culprit seemed to be chronic
infection with hepatitis B virus (HBV). On average, about 12-13% of our
study subjects were chronically infected with the virus. In some areas,
one-half of the people were chronically infected! To put this into perspec-
tive , only 0.2-0.3% of Americans are chronically infected with this virus.
But there's more. In addition to the virus being a cause of liver cancer
in China, it seems that diet also plays a key role. How do we know? The
blood cholesterol levels provided the main clue. Liver cancer is strongly
associated with increasing blood cholesterol,III and we already know
that animal-based foods are responsible for increases in cholesterol.
So, where does HBV fit in? The experimental mice studies gave a
good signal. In mice, HBV initiated the liver cancer but the cancer grew
in response to the feeding of higher levels of casein. In addition, blood
cholesterol also increased. These observations fit perfectly with our hu-
m a n findings. Individuals who are chronically infected with HBV and
who consume animal-based foods have high blood cholesterol and a
high rate of liver cancer. The virus provides the gun, and bad nutrition
pulls the trigger.
A very exciting story was taking shape, at least to my way of think-
i n g . It was a story full of meaning and suggestive of important principles
that might apply to other diet and cancer associations. It also was a
story that had not been told to the public, and yet it was capable of sav-
ing lives. Eventually, it was a story that was leading to the idea that our
most powerful weapon against cancer is the food we eat every day.
105
LESSONS FROM CHINA
So there we had it. The years of animal experiments illuminated
profound biochemical principles and processes that greatly helped to
explain the effect of nutrition on liver cancer. But now we could see that
these processes were relevant for humans as well. People chronically
infected with hepatitis B virus also had an increased risk of liver cancer.
But our findings suggested those who were infected with the virus and
who were simultaneously eating more animal-based foods had higher
cholesterol levels and more liver cancer than those infected with the
virus and not consuming animal-based foods. The experimental animal
studies and the human studies made a perfect fit.
PULLING IT TOGETHER
Almost all of us in the United States will die of diseases of affluence. In
our China Study, we saw that nutrition has a very strong effect on these
diseases. Plant-based foods are linked to lower blood cholesterol; ani-
mal-based foods are linked to higher blood cholesterol. Animal-based
foods are linked to higher breast cancer rates; plant-based foods are
linked to lower rates. Fiber and antioxidants from plants are linked to a
lower risk of cancers of the digestive tract. Plant-based diets and active
lifestyles result in a healthy weight, yet permit people to become big and
strong. Our study was comprehensive in design and comprehensive in
its findings. From the labs of Virginia Tech and Cornell University to the
far reaches of China, it seemed that science was painting a clear, con-
s i s t e n t picture: we can minimize our risk of contracting deadly diseases
just by eating the right food .
When we first started this project we encountered significant resis-
tance from some people. One of my colleagues at Cornell, who had been
involved in the early planning of the China Study, got quite heated in
one of our meetings. I had put forth the idea of investigating how lots of
dietary factors, some known but many unknown, work together to cause
disease. Thus we had to measure lots of factors, regardless of whether or
not they were justified by prior research. If that was what we intended to
do, he said he wanted nothing to do with such a "shotgun" approach.
This colleague was expressing a view that was more in line with
mainstream scientific thought than with my idea. He and like-minded
colleagues think that science is best done when investigating single-
mostly known-factors in isolation. An array of largely unspecified fac-
tors doesn't show anything, they say. It's okay to measure the specific
effect of, say, selenium on breast cancer, but it's not okay to measure
THE CHINA STUDY
106
multiple nutritional conditions in the same study, in the hope of identi-
fying important dietary patterns.
I prefer the broader picture, for we are investigating the incredible
complexities and subtleties of nature itself. I wanted to investigate how
dietary patterns related to disease, now the most important point of this
book. Everything in food works together to create health or disease. The
more we think that a single chemical characterizes a whole food, the
more we stray into idiocy. As we shall see in Part IV of this book, this
way of thinking has generated a lot of poor science.
So I say we need more, not less, of the "shotgun approach." We need
more thought about overall dietary patterns and whole foods. Does this
mean that I think the shotgun approach is the only way to do research?
Of course not. Do I think that the China Study findings constitute abso-
l u t e scientific proof? Of course not. Does it provide enough information
to inform some practical decision-making? Absolutely.
An impressive and informative web of information was emerging
from this study. But does every potential strand (or association) in this
mammoth study fit perfectly into this web of information? No. Although
most statistically significant strands readily fit into the web, there were a
few surprises. Most, but not all, have since been explained.
Some associations observed in the China Study, at first glance, were
at odds with what might have been expected from Western experience.
I've had to use care in separating unusual findings that could be due
to chance and experimental insufficiency from those that truly offered
new insights into our old ways of thinking. As I mentioned earlier, the
range of blood cholesterol levels in rural China was a surprise. At the
time when the China Study was begun, a blood cholesterol range of
200-300 milligrams per deciliter (mgldL) was considered normal, and
lower levels were suspect. In fact, some in the scientific and medical
communities considered cholesterol levels lower than 150 mgldL to be
dangerous. In fact, my own cholesterol was 260 mgldL in the late 1970s,
not unlike other members of my immediate family. The doctor told me
it was "fine, just average."
But when we measured the blood cholesterol levels in China, we
were shocked. They ranged from 70-170 mgldL! Their high was our
low, and their low was off the chart you might find in your doctor's
office! It became obvious that our idea of "normal" values (or ranges)
only applies to Western subjects consuming the Western diet. It so
happens, for example, that our "normal" cholesterol levels present a
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LESSONS FROM CHINA
significant risk for heart disease. Sadly, it's also "normal" to have heart
disease in America. Over the years, standards have been established that
are consistent with what we see in the West. We too often have come to
the view that u.s. values are "normal" because we have a tendency to
believe that the Western experience is likely to be right.
At the end of the day, the strength and consistency of the majority
of the evidence is enough to draw valid conclusions. Namely, whole,
plant-based foods are beneficial, and animal-based foods are not. Few
other dietary choices, if any, can offer the incredible benefits of looking
good, growing tall and avoiding the vast majority or premature diseases
in our culture.
The China Study was an important milestone in my thinking. Standing
alone, it does not prove that diet causes disease. Absolute proof in science
is nearly unattainable. Instead, a theory is proposed and debated until the
weight of the evidence is so overwhelming that everyone commonly ac-
cepts that the theory is most likely true. In the case of diet and disease, the
China Study adds a lot of weight to the evidence. Its experimental features
(multiple diet, disease and lifestyle characteristics, and unusual range of
dietary experience, a good means of measuring data quality) provided an
unparalleled opportunity to expand our thinking about diet and disease
in ways that previously were not available. It was a study that was like a
flashlight that illuminated a path that I had never fully seen before.
The results of this study, in addition to a mountain of supporting
research, some of it my own and some of it from other scientists, con-
vinced me to turn my dietary lifestyle around. I stopped eating meat
fifteen years ago , and I stopped eating almost all animal-based foods,
including dairy, within the past six to eight years, except on very rare
occasions. My cholesterol has dropped, even as I've aged; I am more
physically fit now than when I was twenty-five; and I am forty-five
pounds lighter now than I was when I was thirty years old. I am now at
an ideal weight for my height. My family has also adopted this way of
eating, thanks in large part to my wife Karen, who has managed to create
an entire new dietary lifestyle that is attractive, tasty and healthy. This
has all been done for health reasons, the result of my research findings
telling me to wake up. From a boyhood of drinking at least two quarts
of milk a day to an early professional career of scoffing at vegetarians, I
have taken an unusual turn in my life.
However, it has been more than my own research that has changed
my life. Over the years, I have gone well beyond our own research find-
THE CHINA STUDY
108
ings to see what other researchers have found regarding diet and health.
As our research findings expanded from the specific to the general, the
picture has continued to enlarge. We now can look at the work of other
scientists to put my findings into a larger context. As you shall see, it is
nothing short of astonishing.
DISEASES OF AFFLUENCE
HERE IN AMERICA, we are affluent, and we die certain deaths because of it.
We eat like feasting kings and queens every day of the week, and it kills
us. You probably know people who suffer from heart disease, cancer,
stroke, Alzheimer's, obesity or diabetes. There's a good chance that you
yourself suffer from one of these problems, or that one of these diseases
runs in your family. As we have seen, these diseases are relatively un-
k n o w n in traditional cultures that subsist mostly on whole plant foods,
as in rural China. But these ailments arrive when a traditional culture
starts accumulating wealth and starts eating more and more meat, dairy
and refined plant products (like crackers, cookies and soda).
In public lectures, I start my presentation by telling the audience
my personal story, just as I have done in this book. Invariably, I get a
question at the end of the lecture from someone who wants to know
more about diet and a specific disease of affluence. Chances are that you
yourself also have a question about a specific disease. Chances are, too,
that this specific disease is a disease of affluence, because that's what we
die of here in America.
You might be surprised to know that the disease that interests you
has much in common with other diseases of affluence, especially when
it comes to nutrition. There is no such thing as a special diet for cancer
and a different, equally special diet for heart disease. The evidence now
amassed from researchers around the world shows that the same diet
that is good for the prevention of cancer is also good for the prevention
109
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THE CHINA STUDY
110
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of heart disease, as well as obesity, diabetes, cataracts, macular degener-
ation, Alzheimer's, cognitive dysfunction, multiple sclerosis, osteoporo-
sis and other diseases. Furthermore, this diet can only benefit everyone,
regardless of his or her genes or personal dispositions.
J
All of these diseases, and others, spring forth from the same influ-
ence: an unhealthy, largely toxic diet and lifestyle that has an excess of l
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sickness-promoting factors and a deficiency of health-promoting fac-
tors. In other words, the Western diet. Conversely, there is one diet to
counteract all of these diseases: a whole foods, plant-based diet.
The following chapters are organized by disease, or disease grouping.
Each chapter contains evidence showing how food relates to each dis-
ease. As you go through each chapter, you will begin to see the breadth
and depth of the astonishing scientific argument favoring a whole foods,
plant-based diet. For me, the consistency of evidence regarding such a
disparate group of diseases has been the most convincing aspect of this
argument. When a whole foods, plant-based diet is demonstrably ben-
eficial for such a wide variety of diseases, is it possible that humans were
meant to consume any other diet? I say no, and I think you'll agree.
America and most other Western nations have gotten it wrong when
it comes to diet and health, and we have paid a grave price. We are sick,
overweight and confused. As I have moved on from the laboratory stud-
ies and the China Study and encountered the information discussed in
Part II, I have become overwhelmed. I have come to realize that some
of our most revered conventions are wrong and real health has been
grossly obscured. Most unfortunately, the unsuspecting public has paid
the ultimate price. In large measure, this book is my effort to right these
wrongs. As you will come to see in the following chapters, from heart
disease to cancer, and from obesity to blindness, there is a better path
to optimal health.
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