The China Study
By: T. Colin Campbell &
Thomas M. Campbell II, M.D.
Author: T. Colin Campbell Responds
To Criticism Of The China Study
Sales of our book, "The China Study"
co-authored by my son, Tom, has exceeded
We also are delighted with the 300 or so on-line reviews and emails that speak
of very positive personal health benefits.
But, not all readers agree. A small number (5-10%) have not only disagreed,
but have done so rather vigorously and vehemently. I have accepted with
interest these commentaries, mostly assuming that our book must be having
I have not been inclined to respond to these relatively few critics. Yet, a few
friends and colleagues have asked that I consider doing so, especially
because a couple of the seemingly well-researched commentaries are being
vigorously promoted far and wide.
These include, for example, commentaries by Mr. Chris Masterjohn and an
anonymous Mr. "JayY". So, here goes my rebuttal.
I have several concerns with these critiques.
First, these writers do not understand the overarching theme of our book.
They even misunderstand what scientific discovery is all about—at least the
version of discovery that I have learned over the past half century.
Second, these critics--at least for Masterjohn and his enthusiasts— are
following an agenda which promotes a diet high in cholesterol, fat and animal
protein, which is the mission of an organization to which Masterjohn belongs.
Third, they question the misleading title of our book, and on this point, I agree
Although I would like to respond to each of their specific items, I believe that
discussing these broader points will suffice.
The strategy that we used in our book was designed to explain how I came to
have a worldview of diet and health, both personally and professionally, that
was almost diametrically opposed to what I had at the beginning of my 50-year
In planning the strategy for our book to tell this story, we wondered: Do we
simply summarize a bunch of studies favoring my new views and run the risk
of selecting only the evidence that I liked? Or do we summarize, without
judgment, both the pro and con evidence, only to leave the reader more
confused? We chose neither.
We decided to tell the story how I personally learned it and why I was willing to
recommend it for my family, my friends and myself. In this way, the reader
decides whether the message is as convincing as I found it, perhaps even
Our book starts with a short recounting of my personal background and
professional training that may have influenced my early thinking. Mainly, I was
raised on a dairy farm, milking cows while believing in the great health value of
the typical high fat, animal protein based American diet.
On our farm, for example, we were paid more for high fat milk than for low fat
milk. To the extent that I even thought about such things, I also believed that
cow's milk was the nearest thing to Nature's most perfect food, being
especially rich in protein and calcium.
Eventually, it was on to my doctoral dissertation research at Cornell University
when I investigated with my professors how to produce more not less animal
protein; because of the widespread belief that so-called 'high quality' animal
protein was the quintessential hallmark of good health.
I then began my formal research career investigating a very narrow topic, the
dietary causes of primary liver cancer. Each of the experiments in this early
research was quite focused and a variety of experimental designs were used.
I certainly had no preconceived ideas where our research might be headed
except, possibly, for my bias in favor of the typical American diet, high in fat
and animal-based protein.
Our research began with an anecdotal observation in children that coincided
with an experimental animal study in India, then proceeded through a
widening array of basic laboratory experiments and hypotheses, eventually to
involve an unusually comprehensive human observational study in China.
As the years progressed, our research, which was handsomely funded for
most of my career by the U.S. National Institutes of Health (NIH), was
producing more than a few findings that did not agree with my training or with
my preconceived hypotheses.
At times, these findings were provocative and frustrating, however well our
experiments may have been planned and executed. These experiments often
turned up more questions than answers.
Nonetheless, I was also being reminded that if a more comprehensive truth
were emerging from these detailed, isolated and sometimes controversial
experiments, this truth had to be consistent both with a variety of experimental
study designs, with real life conditions and with a rational biological
explanation, among other criteria.
These considerations and observations of mine are important for
understanding my criticisms of the commentaries of these writers. In effect,
our research was conducted with an eye toward breadth, consistency,
plausibility and, eventually, human health. It was not emphasizing the results
of one experiment or one bit of data.
In contrast, the critics are uncritically using highly selected detailed
observations with no respect for context. They rely rather heavily, for
example, on choosing selected but uncorrected correlations (associations of
one variable with another) from the huge number (about 100,000 or so) that
were published in the 894-page China Project monograph itself.
Moreover, they emphasize the results of this one project in China as if it were
the whole story in the book. This is wrong, quite literally, dead wrong. They
not only miss the connectedness of the observations in this study with other
research presented in the book, but also they are selecting and interpreting
from this study individual unadjusted correlations out of context, perhaps to
please their own biases.
It is important to understand both the limitations and the interpretations of
these correlations. In contrast to these critics, most readers seem to have
understood that there is far more to our book than the China Project. Indeed,
this project represents only one of eighteen chapters in the book.
As my own research experience so well illustrated for me, no one study can
define an emerging whole truth, or worldview. When most researchers do
experiments in an area as biologically complex as diet and health, they almost
always focus on very specific hypotheses, investigating how single agents
cause specific effects, often by so-called single mechanisms (I also followed
such a path).
But these kinds of experiments have limitations both in their design and in
their underlying hypotheses. The combination of a limited design and a
narrowly focused hypothesis for individual experiments can only give
impressions of a larger truth, even though each experiment may be well done.
It is only after doing varied experiments is it possible to begin constructing a
network of evidence and articulating a larger truth.
At least, this is the way research should be done. Unfortunately, this often
fails to take place. Instead, researchers get anxious and speculate beyond the
results of a single experiment thus giving rise to the perception that a very
broad truth has been discovered or is emerging. This especially happens
when there are financial implications.
We tried in our book to avoid this problem by chronologically reporting on the
main experiments during my career, along with the research of others, to
elaborate a larger view that I thought was taking shape.
We felt that this chronology of experiments respects readers, leaving them to
decide whether they agree or disagree. It's about connecting the dots, so to
It is quite easy to find a weakness or an aberrant observation in every single
experiment. If executed and interpreted within the context of a larger
worldview/hypothesis, each experiment gives direction as to what to do next,
perhaps even suggesting a sharp turn in a new direction.
If a larger truth is emerging, it seldom if ever depends on one experiment.
Rather, it is a matter of accumulating evidence for a series of experiments,
especially to see if the evidence is logically connected and consistent.
In my research career, an unexpected trend was emerging not only from the
results of our experiments, but also from the findings of others. Although this
trend initially was quite provocative, it nonetheless was beginning to show
promise for human health.
The China Project results are no exception to these limitations of single
experiments. It was very large, unique and comprehensive but it was
observational (i.e., not interventional), simply observing things as they were at
a single point in time. It provided an exceptionally large number of
hypothetical associations (shown as statistically assessed correlations) that
may indicate but does not prove cause and effect relationships.
These unanalyzed correlations are considered raw or crude. It is highly
unusual to find such 'raw' data in a scientific report because, in part, untrained
observers may misunderstand such raw data.
For the monograph, we were somewhat uncertain whether to publish such
raw data but decided to do so for two principle reasons.
First, we wanted to make these data available to other researchers, while
hoping that data misuse would not be a significant problem.
Second, because these data were collected in rural China at a time when data
reliability might have been questioned, we chose to be as transparent as
We discussed data use and misuse on pp. 54-82 of the China Project
monograph that curiously was overlooked by Masterjohn.
In brief, while fully understanding the pitfalls, the purpose of interpreting data
of this kind is to extract from these crude correlations their true correlation
counterparts, then interpret these counterparts within the context of
information derived from other sources.
In making these adjustments and interpretations, we want to consider, for
1) Whether there is a sufficiently broad range of exposure for each of the
variables comprising the associations (e.g., a true association of breast cancer
with dietary fat consumption can only be detected if there is a sufficient
range—above zero—for each of these variables).
2) Whether there are confounding factors (e.g., high fat consumption might
reflect high animal protein consumption, low dietary fiber consumption or
even ownership of TVS).
3) Whether the associations are biologically plausible (e.g., being consistent
with existing clinical information, especially within this clinical project).
4) Whether these associations collectively reflect a consistent dietary pattern,
among other considerations.
In addition to these individual associations, we also had opportunities to
evaluate aggregate associations, keeping the same caveats and
considerations in mind.
These critics, who are mischievously posing as qualified scientists, have
committed errors that expose either their ignorance of basic research
principles and/or their passionate following of an unstated agenda.
By superficially citing uncorrected crude correlations from the China Project
monograph, they show a serious lack of understanding not only of the
fundamentals of scientific research but also of the principles of statistics,
epidemiology and nutrition.
To make matters worse, they have selected correlations that reflect an
alternative agenda or bias that has nothing to do with objective science.
It was this suspicion of bias that reminded me of an eerily similar commentary
earlier written by Ms. Sally Fallon, President of a special interest group located
in Washington, DC, known as the Weston A. Price Foundation (WAPF).
Ms. Fallon's commentary was widely circulated in cyberspace several years
before we published our book. Thus I began to wonder who was WAPF and
especially who was Weston A. Price, now the adopted 'patron saint' of WAPF.
Price's main book was published in the late 1930s—at least this is the book
that is most commonly cited by WAPF. I bought the book, carefully read it and
learned that the WAPF staff and associates substantially exaggerate, in my
opinion, the importance of Price's observations and the importance of his
Price was a dental surgeon who visited more than a dozen indigenous
populations around the world and became quite impressed with the overall
good health of these geographically isolated people when compared with their
kin who had become exposed to commerce from other lands. He seemed to
regard these native peoples as the nearest link to our own past.
With background in dentistry, Price assessed their health mainly by dental
caries incidence and facial structures, supplementing his observations with
many photographs. Although he made certain inferences about health in
general, he published no reliable empirical data to support this view.
In brief, Weston Price's suggestion that dental caries was associated with the
introduction of commerce (probably including processed and sweetened food
products) was quite convincing, not unlike similar reports of others.
He also speculated about an 'X' factor in milk fat, supposedly suggesting
health benefits for cow's milk, but no follow-up findings on this 'X' factor
consistent with human health have since been reported. In no way did Price
publish reliable data in this book that could be used to evaluate the
relationship of food with overall health.
He did speculate, however, with some evidence, on the loss of nutritional
value of food at that time (1920s-1930s) as a result of soil depletion and
Excepting his observations on an association of dental caries incidence with
processed food, Price's study, in my opinion, is of limited scientific value.
The WAPF enthusiasts nonetheless suggest that this was a major survey of
the relationship of food with human health, perhaps being one of the most
important. Either by statements or inferences, WAPF writers and enthusiasts
then go on from Price's meager observations to aggressively claim health
benefits for animal based foods, especially those associated with
unprocessed, raw cow's milk produced by grass-fed animals.
It was the aggressiveness and supreme confidence of the WAPF people that
was, for me, puzzling. Was this group scientifically experienced and qualified
to be so certain of their views? They certainly wrote well and presented their
arguments in a seemingly scientific manner—at least for the lay reader.
I therefore became engaged in an email dialogue with Mr. Chris Masterjohn to
learn about his background and his sources that seemed to be so closely
aligned with WAPF interests.
I learned that Masterjohn was a 24 year old 'chapter leader' of WAPF in
Massachusetts. He claimed that he was a former vegetarian who nearly lost
his life (according to his account) because of his following the earlier advice of
He said that he only knew 'former' not present vegetarians and was convinced
that every vegetarian would eventually learn the error of their ways. Most
importantly, he has had no first hand experience or training in experimental
nutrition research and no professional peer reviewed publications.
He has his own website that promotes consumption of high cholesterol high
fat foods. He also writes for the WAPF website. I am impressed with his
writing skills but not with the content of his argument.
I also wonder, however, whether his writing skills have been honed and
reviewed by his superior, Sally Fallon, who has training in English.
(I recently saw, for example, a final Masterjohn draft report that was circulated
to a large group of people for comment. In this report, he concludes that dairy
is not an important source of dioxin, opposite that reported in a 10-year report
by EPA, among others.)
The fact that the WAPF people and their enthusiasts are so hostile to our book,
to me personally and to anyone reflecting similar views needs some
Masterjohn, for example, claims in his website that, in effect, I am primarily
being subservient to the animal rights agenda and more specifically to the
Physicians' Committee for Responsible Medicine (PCRM) who according to
Masterjohn, are associated with PETA (People for the Ethical Treatment of
(I have been for some years on the PCRM science advisory board and am
pleased to continue doing so.)
He assigns guilt by association for me by pointing out how the US Department
of Justice has labeled PETA a domestic terrorist threat.
Much of our earlier—and seminal—research was conducted on experimental
animals. This was an activity that does not please the more vocal animal
rights advocates, some of whom have pleaded with me to eliminate the animal
research findings from my public lectures.
Then there is the anonymous and enigmatic 'JayY' who is vigorously
submitting a Masterjohn/Fallon look-alike commentary to counter many of the
positive reviews on Amazon.com.
He says: "I've never sat on a government advisory panel, never attended even
a single university lecture, and cannot yet boast of having the same volume of
published literature as Campbell, but I'm smart enough to know most of the
claims made in his book are utter rubbish."
Oh, that all of us might be so fortunate. I can't help but wonder whether he is
advocating the abolition of universities for, in his case, he became unusually
intelligent without such training.
Further on, he adds: "Within minutes of beginning his book, even the dullest
reader will quickly realize that Campbell is on a zealous mission against animal
protein, which he believes to be public health enemy number one."
No, this is not my choice for public enemy number one. Rather, I am now
wondering whether overzealous, arrogant but untrained critics are a more
Masterjohn also strongly laments, both on the WAPF website and on his own
website, the negative publicity long given to high cholesterol foods like eggs,
butter and liver, and says that these are "super foods" that must be
He claims that dietary cholesterol itself must be consumed and that the
concept of good and bad blood cholesterol (HDL and LDL, respectively) is a
He then goes on to label the government's diet and health recommendations
to lower dietary fat as "totalitarian".
Strong views, strong language, lots of confidence, especially for someone
with no nutrition research training or experience. When I asked him who
supports WAPF, he told me that farmers, among others, were important
Because factory farms now produce most of the food in the U.S., I would be
more comfortable if I knew how much influence these 'farmer' conglomerates
have on WAPF itself.
I don't decry the industry promoting its product—honestly of course—but I
question the blatant attempt of WAPF writers to convey seemingly objective
opinion that favors the industry without making clear their serious lack of
qualifications and conflicts of interest.
WAPF Founder Sally Fallon who has Bachelors and Masters degrees in
English sums up her organization's views as follows:
"Animal fats and cholesterol are not villains but vital factors in the diet,
necessary for normal growth, proper function of the brain and nervous system,
protection from disease and optimum energy levels."
It is time to seriously question the scientific objectivity and professional
qualifications of WAPF staffers and their writers. It also is time to question
their excessive exaggeration of Weston A. Price's observations.
I would be remiss, however, not to mention two areas of agreement. First,
WAPF have emphasized the questionable value of highly processed
essentially plant based foods whose calories are mostly comprised of refined
carbohydrate (e.g., sugar, white flour) and oils, both plant based. I concur with
Indeed this is the main reason that my son and I emphasize in the book
"whole" plant based foods, not these plant food fragments.
Second, some have been critical of our book title that incorrectly implies that
the book's overall message mainly depends on the China Study itself (it is only
one chapter in our book).
This title was the choice of our publisher. His view was based on marketing
considerations and certainly was not due to the fact that the entirety of the
book is represented by the findings from the China Project.
In summary, our book and my views are not about one study, one or even a
few nutrients, or about one or a few aberrant but unadjusted correlations in
the study in China. Moreover, we made this point on p. 106 of our book, as
Do I think the China Study findings constitute absolute scientific proof? Of
course not. Does it provide enough information to inform some practical
An impressive and informative web of information was emerging from this
study. But does every potential strand (or association) in this mammoth study
fit perfectively 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 [by
considering the adjustments discussed above].
My present views on diet and health are based on the consistency of the vast
majority of evidence produced by a wide variety of studies. I see three types
of evidence that has most influenced my present views.
First, there is the research data from our own studies that are summarized in
Second, there is the evidence obtained by many other laboratories, a sample
of which is summarized in our book.
Third, there is, perhaps, the most important evidence of all, the clinical
experiences of the practicing physicians who I had come to know, especially
those of Drs. John McDougall, Caldwell Esselstyn, Jr., Terry Shintani, Joel
Fuhrman and Alan Goldhamer.
For me, these medical practitioners, entirely on their own initiative and
knowledge, were advising, with impressive success, their patients with the
same information that I had come to know from the scientific literature and
laboratory. The proof is in the pudding, so to speak. The idea works.
By: T. Colin Campbell
T. Colin Campbell