EXTRA! EXTRA! According to Reuters News Agency, the World Bank has just "…approved a $93.5 million loan to help nearly 140,000 Chinese farmers raise cattle in addition to their normal crops." When added to matching funds from other sources, a total of about $200 million, this represents about $1,400 invested per farmer to increase his annual income $50-$200, using World Bank figures for calculation. And that's not all! China will also get 130 new cattle feedlots and employment for about an extra 3,000 workers.
And here's a side benefit, according to a World Bank internal document: "Beef has traditionally been a luxury meat [in China], consumed only during festival days, but the advent of the hotel-restaurant-institutional segment and self-service chain grocery stores offering a variety of chilled or frozen meat cuts is greatly assisting the consumer acceptance of beef in relation to other meats". In other words, while alleviating poverty, these funds will make it possible to service the fast food chains such as McDonald's.
I know first-hand much of this story because I was invited by a couple of brave staffers at The Bank to share my views, as well as the evidence from our comprehensive nationwide diet and health study in China. And there were others who added their views not only on the health consequences but also on the likely environmental impact of this project. After two lectures, a paper summarizing the evidence from our China study, commentaries on the presentations of others, considerable correspondence, still earlier lectures at The Bank and correspondence sent to World Bank President James Wolfensohn , we failed to get the decision we thought made eminently more sense. We did not believe that spending this much money to encourage the production of a very expensive food, only then to produce very expensive diseases, was in the best interest of anyone except those in the trade.
With all due respect to the sincere efforts and eloquence of the few brave souls at The Bank who sought and arranged what discourse did take place, it became abundantly clear to me that those who make the really critical and final decisions will arrogantly avoid the relevant evidence if it does not suit their alternative agenda.
It is, of course, true that in China and elsewhere there are many policy makers who sincerely believe that an improved market for beef production and consumption is in their country's best interests. There also are the vast majority of Chinese citizens who will behave just as we in the West did during a similar phase of our history. When given the economic means to do so, they, like us, will consume beef and other animal-based foods simply for its taste. They, like us, will have been indoctrinated with the presumption that eating beef is a sign of civilization , a birthright, and an indication of wealth, status and power.
I could spend the rest of this editorial summarizing the evidence, which has been documented in many major expert-panel reports and original investigations in peer-reviewed science journals. I briefly share some of this evidence in two companion pieces to this article 2. Instead, I will speak to another view, namely, whether people really want to consider evidence that may be contrary to their own interests.
There is something very profound and very personal about the question of whether to be a carnivore (There is no philosophical difference between a carnivore and an omnivore, a word we generally find to be more comfortable - carnivores just don't like vegetables and fruit). People whose minds are imprisoned within the world view of consuming the juices, flesh and organs of animals seem to have a very difficult time even imagining evidence to the contrary. They prefer to be oblivious to the health evidence against these products or, at times, to be hostile to the messengers of such evidence.
In an internal e-mail correspondence at The Bank, a senior Bank staffer responsible for the beef cattle project wrote the following when asked about potential problems associated with the consumption of animal-based foods:
Nonetheless, following this and other 'dialogue' of a similar nature, we were led to believe during the spring of 1998 that the project had been dismantled and that we had been persuasive in our arguments against its funding. During the summer of 1999, however, we got word that it was being resurrected, if indeed it was ever tabled. Five speakers, including myself, were invited, including a senior Bank staffer quite familiar with, and presumably supportive of the proposal. It was during the panel discussion following the presentations that I first learned from my fellow Bank panelist of the prevailing view among the project advocates within the Bank. We learned, quite surprisingly, that the evidence supporting the health value of a plant-based diet was not sufficiently persuasive to these folks, who also did not attend the symposium, thus suggesting that they really had little or no interest in the evidence.
What are these project advocates thinking, especially after so many national and international reports from expert panels over the past quarter century have concluded that we should be shifting to a plant-based diet? And what about the evidence from rural China itself, the most comprehensive survey of any country, showing a highly significant association between the consumption of even small amounts of animal-based foods and increasing prevalence of heart disease, cancer, and similar diseases so common here in the West?
For me, being convinced of the evidence in favor of a plant-based diet is not about the evidence or the facts. Instead, it is about issues of a very different kind. Ignorance I can tolerate, for it means that we have failed to adequately articulate the evidence. Personal preference in the face of actually knowing the evidence also is tolerable, for who am I to tell others what to eat? But arrogance, that state of mind which aggressively determines important policies for the public at large while intentionally avoiding the evidence, is a very different matter.
Decisions of this sort are not new, of course. Please be assured that I am not quite that naïve. Like so many have said before, those who make the golden rules are the very same ones who have the gold. Such behavior has gone on for a very long time and it is not expected to be suspended any time soon. The arguments against the consumption of animal-based foods, on grounds of ill health, is very old indeed.
Socrates wondered about the consequences of people becoming affluent, especially as they moved to urban centers. He claimed that there would be a need for "great quantities of all kinds of cattle for those who wish to eat them". He then went on to ask, "…shall we not experience the need for medical men to a much greater extent under this than under the former [dietary] regime?" He also was far ahead of his time when he wondered how it would be possible to get the extra land for producing cattle meat, when compared with the land required to produce the same amount of food from plant material. Why was Socrates, and others even before him, 2,500 years ago, so smart while we, eons later, are so dumb? It seems that we have learned far more how to manipulate information, and far less how to understand and to share information.
Although my cynicism remains relatively intact, I could be persuaded that maybe we are about to enter a new and more promising age. Perhaps, we could use these rapidly emerging and powerful information technologies to spread the word ourselves, without going through the jungle of bureaucracy heretofore controlled by the few for the few. But--and this is very important--we also must figure out ways to promote information that is articulate, sincere, and reliable if we will ever be able to develop this desperately needed new world view.
Visit Dr. Campbell's website, New Century Nutrition, at www.newcenturynutrition.com.
Crichton-Browne, J. S. (1908). Parsimony in Nutrition. London, Funk and Wagnalls.SUPPORTING DOCUMENT # 1: T. COLIN CAMPBELL'S LETTER TO JAMES WOLFENSOHN
November 18, 1999
Mr. James Wolfensohn
Dear Mr. Wolfensohn,
I write to share with you my concern that the World Bank Group is contemplating the funding of the "China-Smallholder Cattle Development" project (#CNPE45264), for approximately $200 million. I take considerable interest in this project because of my agricultural background and training, my two decades of health sector research work in China, and my having given four invited seminars on this topic during the past eight years at the Bank.
In this note, however, I will limit my remarks to the human health consequences of this project, since others have addressed the issues of environmental degradation, expensive land use, the undoubted need for imported grain for fattening, and the highly unlikely event that the needs of the poor will be addressed as proposed. I nonetheless have great concern for these other issues as well.
First it should be pointed out that virtually no serious policy statement of the recent two-three decades has advocated increased consumption of beef as a means of improving health. Indeed, virtually all have advocated exactly the opposite. These documents, several of which I have been a co-author, advisor, or reviewer, include comprehensive, substantially documented publications of Expert Panels of the National Academy of Sciences (1982, 1989), the U.S. Surgeon General's Office (1988), the World Health Organization (1992), the American Heart Association (several since the 1970s), the American Cancer Society (1998), and the World Cancer Research Fund/American Institute for Cancer Research (1997). Indeed, the latter report, with Chinese representation and comprised of 16 outstanding scientists from 10 different countries, listed as its first recommendation for the world "Choose predominantly plant-based diets rich in a variety of vegetables and fruits, pulses (legumes) and minimally processed starchy staple foods."
It is abundantly clear that it is NOT necessary that beef consumption be encouraged in order to obtain so-called "high quality" protein, as stated in the Bank proposal. This phraseology of "high quality" means nothing of the kind; it is only a matter of increased utilization efficiency and this is not needed, especially given the abundant findings showing that such protein intake increases blood cholesterol levels, encourages cancer growth, enhances calcium loss from the body, and favors greater risk for diabetes, among other adverse effects. To desire "greater efficiency of utilization" only to produce such effects makes no sense.
There are several incorrect assumptions in the proposal, some stated and some implied, that need to be addressed. It is said, for example, that "the increasing demand for beef [is mostly driven] by urban consumers", but what is omitted in this comment are the findings showing that this is the very same urban group who also are now experiencing remarkable increases in those diseases most affected by this very same dietary practice. Age-adjusted incidence rates in China for coronary heart disease, several cancers, diabetes and osteoporosis all are rapidly rising in parallel with these food consumption trends; indeed, in many of the large urban centers, heart disease and cancer are now the two leading causes of death (and this is NOT EXPLAINED by a reduction of communicable diseases, only to be replaced by these 'new' chronic degenerative diseases).
I should also add that, together with our Chinese and British colleagues, we have twice surveyed 130 villages in China more comprehensively than any such study in the history of medicine (Chen et al, 1991, 896 pp., Oxford University Press, Cornell University Press, China Peoples' Publishing House). Among these villages, there was a wide range of disease rates, yet the individuals living in these various regions lived in the same regions all their lives, and the food they consumed was produced locally. It was an ideal experimental setting: diseases were geographically localized but people and their food habits over time were very stable.
Remarkably, from many diet-disease perspectives, we found that from a baseline of very low fat diets (6-10% of energy) up to a level of about 24% of energy, from mean blood cholesterol levels of about 90 mg/dL up to 170 mg/dL, and from intakes of virtually no animal protein up to only about 20% of total protein intake (the mean intake in the U.S. is 70% of total), we observed many statistically significant associations supporting the hypothesis that even small additions of animal based foods to the diet lead to increases in chronic degenerative diseases. This was unexpected at the beginning of the study because we had thought that small intakes of animal based foods and these uniformly low levels of blood cholesterol (promoted by the consumption of animal-based foods) would be below the threshold of effect. Thus, this observation, based on so many cause-and-effect associations, is quite remarkable and profoundly important, both for China and elsewhere.
We now know all too well the consequences of increasing the consumption of beef and other animal-based foods, with one of the more remarkable being the enormous health care costs associated with this practice. In the U.S., for example, these costs now stand at the world record level of 14% of the GNP (HCFA, Office of the Actuary, July 1999), and many are expecting this to go even higher in the near future. Moreover, the number of in-clinic deaths resulting from the use of our well-tested pharmaceuticals, as reported by the General Accounting Office of the U.S. Government, along with other deaths resulting from medical malpractice and other excesses, give rise to the sad conclusion that the U.S. medical system, itself, is the third leading cause of death in the U.S.
In short, it is clear that the food consumed in the U.S. and the diseases caused by this food together lead to exorbitant societal costs, both in the costs of producing this expensive food and in the costs of disease care (some would call this health care). Moreover, it is the poor of the U.S. who pay, in human suffering, the largest price because about 45 million American citizens now are uninsured (U.S. Census Bureau, 1998, and S. Altman, Brandeis University, 1999). The U.S. system is broke in more ways than one and this is why there is such a unanimity of opinion arising in the above cited expert panel reports who recommend turning our attention to plant-based diets and away from diets containing beef and other animal-based foods.
Although this evidence is from the U.S. and is somewhat typical of other Western countries, it is now clear that this is what can be expected for the developing nations as well, if they follow this same path. In my lectures to policy groups that are experienced and/or interested in China, I often emphasize that the Chinese would do well to learn from our mistakes. Indeed, I find it incomprehensible that the World Bank Group would find it necessary to fund a project that so defies the contemporary trends in health advice worldwide.
And finally I would suggest if you need further corroboration of the substantial risks posed by this project to Chinese citizens' health that you ask the Bank's own internal public health and nutrition experts, such as Alan Berg, Milla McLaughlin, Thierry Brun, Harold Alderman, Alan Piazza, or Chris Lovelace for their views.
I do hope that this information might be helpful. My views are based on my having spent my entire career working in this area of health, with much of that time in Asia, especially in China. And I do believe that it is vitally important that construction of future agricultural, food and health policies, whether in China or elsewhere in the developing world, be consistent with good health.
With kind regards,
T. Colin Campbell,
cc. Matthew McHugh,
Esq., Senior Counsel
Also endorsed by the following:
J. Chen, MD
Calvin Thrash, MD
William Harris, MD
Neal Barnard, MD
John A. McDougall,
Division of Nutritional
Junshi Chen, MD
Banoo Parpia, PhD
Division of Nutritional
"Social Consequences of Chinese Economic Reform"
May 23-24, 1997Presentation and objectives
For my presentation, I was asked, firstly, to examine what nutritional changes in China have occurred as a consequence of the recent market reform and, secondly, what impact these changes might be expected to have on social and economic development. My comments are primarily based on the early results (1) of a nationwide comprehensive survey of dietary, lifestyle and disease mortality characteristics in rural China which was initiated in 1983 and which involved a collaboration between the Chinese Academy of Preventive Medicine, the Chinese Academy of Medical Sciences, Cornell University, Oxford University and, more recently, the Taiwan National Research Council.
However, before presenting these findings and commenting on their implications, I should first pause and ponder the intense personal beliefs which often surrounds our understanding of the subject of nutrition.Nutrition knowledge overview
I have found that it is not enough to simply describe nutritional changes, for this leaves to each person's imagination whether these changes are desirable. It is my experience that most people hold fairly strong views on what constitutes good nutrition. Such views are quite personal, often relating more to one's preferences at the table rather than to one's familiarity with, or fidelity to, the scientific evidence.
Views on nutrition are in the same emotive zone as views on sex, politics and religion, all existing at the very core of our being. Such has been the state of nutrition affairs for a very long time, ever since 2500 years ago during the days of the ancient Greek philosophers who offered, in effect, that we are what we eat. So also has this same view held sway in the Orient; in fact, it still may be holding truer to form there than here in the West.
My belief that individual's views on nutrition are too often very personal and without scientific merit is, I admit, a rather cynical, perhaps even arrogant perspective. But please, I beg your indulgence for a moment on this point. I really don't mind what individual people choose to eat for themselves because I value individual choice and individual experience more than whether they abide by my preaching of what I think to be truthful nutrition information. But I do feel a bit of angst, however, when listening to public authorities who develop societal policies on food, agriculture and health and who dispense public funds and administer public programs without having an adequate understanding of the scientific principles of nutrition biology. This troubles me and I make no apologies for my worry.
The predominant world-view on what constitutes good nutritional practices has clearly favored that obtained from diets consumed by the rich and powerful. These diets have been and are still perceived to be those that are generally high in fat, low in fiber, and most importantly, rich in foods of animal origin.
Oftentimes, this diet is considered "Western", a designation reflecting at least historically, its predominance among Western industrialized societies. This view is encased within a profound paradigm which has penetrated virtually every sector of our society and, in so doing, has, in my experience, severely restricted creativity and candor, as much or even more so within science laboratories and medical clinics as anywhere else.
The societies who espouse this way of eating also are the ones which, during the past couple of centuries, scripted the principles and criteria of modern science and produced therefrom the technologies that have underwritten modern medical practice. We call this practice "Western Medicine". And, what's more, these societies mostly are the same ones that unabashedly construct the histories of their own accomplishments, thereby constructing and fixing in place a rigid paradigm of nutrition thinking. And the majority of the historians and scientists from these societies, not surprisingly but perhaps unwittingly, have encouraged views that supported their own personal dietary habits and, lately being within an environment of modern technology and financial largesse, to even create evidence distinctly biased for their own purposes.Trends (1950-1980)
Before presenting the results of our survey work during the 1980s and 1990s in rural China, however, the health trends for the period of about 1950-1980 should be briefly noted. This 1950-1980 period was a time when diet and disease trends occurred under the influence of a centralized command economy, although there is also evidence that geographically localized trends were sometimes found to be responding to local initiative and local incentive.
In spite of a major setback during a severe famine in the late 1950s and early 1960s, China has made remarkable progress during the past half century overcoming what was once considered almost insurmountable and stifling health problems. The progress ranges from substantial successes in reducing infant mortality and increasing life span to the reduction of childhood malnutrition and the prevalence of communicable, infectious diseases. Infant mortality was dramatically decreased by more than 80% and overall life expectancy, mostly a reflection of infant mortality, increased from about 35 years of age just prior to 1950 to 65 years of age in 1980 (Fig 1). Life expectancy is now above 70 years of age even though the infant mortality rate still remains only slightly lower than in 1980, at 38 deaths per 1000 live births. Alan Piazza of the World Bank reported in 1986 (2) that life expectancy at the end of the Second World War was a mere 35 years of age and the proportion of marginally and severely malnourished people was staggering. During the 1950s, I recall the American press consistently reporting that China was a nation unable to feed itself, either then or in the future.
The reduction in the incidence of communicable diseases was particularly impressive. According to Piazza (2), diseases such as smallpox, venereal disease, and cholera were markedly reduced by the mid-1950s, while several widespread parasitic diseases were largely under control by the late 1950s. These improvements were effected through the use of improved vaccines, the extension of the health care system to rural areas, and the more effective use of disease control and treatment methods. The health and anti-epidemic stations that were adopted in the early 1950s to serve the rural areas eventually grew to 2500 by 1964; these were the stations that later were to serve our survey in 1983.
On nutrition, the first task in the early 1950s was simply to increase food availability (2) (Fig. 2). Energy intake in 1950 was 1742 kcal per capita per day, but by 1980 was 2473 kcal per day, more than enough, given the body size and physical activity of the average Chinese. In the early 1950s, fat intake as a percent of energy intake was 11.3% and, by 1980, still was only 12.6%. These data show that the average diet was mostly plant- based, with very little or no added fat or sugar. The average contribution to total energy by animal-based foods was 3.6% in 1950 and was still only 5.8% in 1980. As we shall see from our survey results, it wasn't until the introduction of the market economy in the late 1970s and early 1980s that diet composition started to change.
Data on anthropometric measurements showed that male height-for-age between 1953 and 1982 in China increased by 3.2 cm. per decade, which surpasses that of Europe in the twentieth century and is about equal to that of Japan since 1950 (2). Preliminary analysis of the determinants of body height differences among adults in our 1983 data collection suggested that this dramatic improvement in height-for-age from 1953 to 1982 was more due to a decrease in the prevalence of early childhood communicable diseases than to a decreased prevelance of nutritional deficiencies.
Thus, by about 1980, at the dawn of the market reform period, it is now clear that great advances in public health already were achieved in China, an achievement all the more remarkable because of the unusually low expenditure of public funds and because the average Chinese diet during this time was almost entirely (94-96% of energy) plant-based. Lest this picture be too rosy, it should also be mentioned that, by 1980, significant minorities of Chinese still remained undernourished, infectious and parasitic diseases were still too common in certain areas, and infant mortality rates could still be further reduced.Survey data (1983-present)-basic assumptions
Therefore, I shall spend most of the remainder of my presentation presenting a few summary findings from our comprehensive 1983 survey of dietary, lifestyle, and disease mortality characteristics in rural China, an ongoing collaborative investigation between Cornell University, the Chinese Academy of Preventive Medicine, the Chinese Academy of Medical Sciences, and Oxford University, more lately also including the National Research Council in Taipeh, Taiwan.
This project was conceived in the early 1980s during the time when the National Academy of Sciences was producing its 1982 landmark report on diet, nutrition and cancer (3). At that time, the principal evidence supporting a link between diet and chronic degenerative diseases came from a comparison of countries whose diet and diseases practices were very different. Certain features of Western type diets were found to be strongly associated with certain diseases found in Western type countries. One such relationship was that for dietary fat and breast cancer: the higher the total dietary fat, the higher the breast cancer incidence (Fig 3).
However, this association seemed to be better explained by factors associated with the consumption of diets rich in animal fat (Fig 4),
more than with diets rich in plant fat (Fig 5).
These data illustrate three important points (Fig 6). First, people who migrate from countries with a high risk of disease to countries with a low risk of disease (or the reverse) gradually acquire the risk of disease of the country to which they move, while keeping their genes essentially the same.
These findings show that, if genes between individuals play a role in the determination of disease--and they undoubtedly do, then diet and lifestyle factors are largely able to control whether these genes produce products which lead to disease.
Second, substantial prevention of disease is possible, not only for breast cancer but also for other chronic degenerative diseases as well. Perhaps even the vast majority of these diseases could be prevented. That is, for each of these diseases, there are countries where disease incidence is very close to nil. Thus, if we could identify the offending risk factors then control them, then these diseases can be prevented without resorting to bizarre and unpredictable interventions such as gene therapy or treatment with highly toxic chemicals.
And third, we need to add a word of caution, substantial caution, on how these data should and should not be interpreted. Using this example, the strong association of dietary fat with breast cancer does not prove that dietary fat, per se, is responsible for these high disease rates. It only means that something characterizing societies consuming high fat diets is associated with disease. Dietary fat might contribute some risk, perhaps more under some circumstances than for others but these data, when standing alone, say little or nothing about how strong this effect might be.
Unfortunately, most researchers since 1982 have focused on dietary fat as the cause of breast cancer and, in my opinion, an enormous amount of wasted funds have been and are being expended. The much-publicized association of dietary fat with breast cancer (as well as many other narrowly focused diet-disease associations) is, in my view, far too parsimonious. The dietary and lifestyle causes of disease usually are far more complex, thus suggesting the need to investigate these associations much more comprehensively.Survey hypothesis and study design.
In 1982, when the China Study was being planned, the best guess for an hypothesis to investigate seemed to be dietary and lifestyle factors associated with the consumption of animal fat, as previously explained. The primary and most comprehensive effect of diet upon the development of chronic degenerative diseases could, very simply, be related to the ratio of foods of animal origin to foods of plant origin where animal fat intake is only a surrogate marker for dietary differences. 'Western' type diets, rich in foods of animal origin, characteristically were high in fat, low in dietary fiber, low in an unusually large number of so-called antioxidant nutrients (e.g. vitamins C, E, and beta-carotene) and other constituents of plant material, and high in the type of protein having a high efficiency of utilization--among many other factors.
Thus, an investigation of people experiencing a range of these diseases and consuming diets mostly comprised of a range of foods, especially a range of constituents of plant derived foods was desired. Such an opportunity presented itself in rural China. Chinese scientists had undertaken a study during the 1970s to eventually show in 1980-81 that mortality rates for about a dozen different cancers were vastly different for different parts of the country (Fig 7).
Across China, diets varied from those rich in plant matter on the one hand to those very rich in plant matter on the other. People tended to consume the same diets from year to year and to reside in the same region most of their lives. Thus, within each reasonably small survey sample area, diet, disease, and residence conditions were reasonably constant. At the same time, across the whole of China, dietary and lifestyle characteristics varied considerably, as illustrated in the highly variable social and economic conditions (Fig 8).
An ideal experimental opportunity and cohort were therefore available to investigate the very general but biologically complex hypothesis that diets ever richer in a variety of foods of plant origin are associated with ever decreasing amounts of these diseases. The biological complexity of this relationship may be considered to be due to the combined effect of countless constituents operating through countless biological mechanisms upon countless varieties of degenerative type diseases.
The study was organized to include 65 counties spanning the full range of mortality rates for seven different cancers. Two villages in each county and 50 adults (25 male, 25 female) and their families per village were selected for the survey and the following information was collected.
The field survey itself was organized and carried out under the direction of Dr. Junshi Chen of the Institute of Nutrition and Food Hygiene of the Chinese Academy of Preventive Medicine in the Fall of 1983 and five kinds of samples and other questionnaire information were collected (Fig 9).
The samples of blood, urine and food collected in the survey were analyzed in the laboratory for a variety of nutritional, viral, hormonal and toxic chemical factors between 1984-1988 while the dietary questionnaire information was assembled and entered into computer storage. After 'cleaning' this massive amount of information during 1989-90, a total of 367 items of dietary, lifestyle and disease characteristics (130 villages, 6500 families) were judged to be reliable and were published in a 900 page monograph in 1991 (both in English and Chinese).
Analysis and publication of this information was begun in 1991 and will continue for many years into the future. (As of 1996, only about 2-3% of the total information has been analyzed, interpreted and published.)Summary indicators: China vs. US
An overview of dietary characteristics shows that diets in rural China were vastly different from diets in the US (Fig 10).
Average intakes of dietary fat and fiber in rural China were, at the time of this survey, markedly different from the US. An especially low intake of foods of animal origin is indicated by the very low intake of animal protein. On average, Americans consume diets containing about 10 times the concentration of animal protein than do rural Chinese. Such a difference obviously indicates major differences in many other dietary and metabolic characteristics as well (Fig 11). For example, blood cholesterol and total fat intake were substantially lower in rural China than in the US.
Energy (calorie) intake, per kilogram of body weight, was about 30% higher in China than the US, yet the prevalence of obesity was much lower in China. This observation is quite remarkable because Chinese energy intake has been standardized for office workers. Thus office worker type people in China consume considerably more energy and are much less inclined toward obesity than 'average' Americans engaged in all manner of work. Undoubtedly, much of increased energy intake in China is attributable to their greater physical activity (most office workers ride bicycles to work) but some of this difference may also be due to the type of diet being consumed. That is, when a very low fat, high plant food diet is consumed, a significantly higher percentage of the energy being consumed may be 'wasted' or burned off as heat instead of being laid down as body fat.Methods of analysis
Our primary aim to date for analyzing and interpreting these data has been directed to an assessment of the more comprehensive and wholistic relationships between causes and effects, a means of assessment traditionally done very poorly by modern, high technology science. We have pursued this aim in two ways. First, disease mortality rates were compared to see if there were any particular tendencies for diseases with common causes to be grouped within similar communities. Then, the dietary and lifestyle factors chiefly associated with these disease groups were identified and associations were assessed.
Second, we hypothesized and investigated associations between specific causes, specific explanatory mechanisms, and specific diseases. Association of these associations of individual factors with individual diseases were then assembled into the whole to see which kind of diet, broadly speaking, was responsible for these associations.
In a sense, the first method initially examines the outside, then peers within, while the second method examines the inside, then looks out. The first describes the whole 'forest' and the main 'trees' which provide the overall appearance. The second examines the trees independently and then attempts to see whether these details match the whole forest description.Aggregate group associations
In relation to the first method, two geographically localized groups of disease were found (Fig 12), showing that each disease in either of these two lists is positively associated with diseases in its own list but inversely associated with diseases in the opposite list.
The first group (A) included diseases characteristic of developing countries while the second group (B) included diseases characteristic of Western countries. Such geographic aggregation of diseases suggests that each disease group tends to have its own set of common dietary and lifestyle causes. Several characteristics measured in the study and possibly representing such common causes were examined. Those which were chiefly associated with Western diseases were total blood cholesterol and urea nitrogen (Fig 13).
Blood urea nitrogen was chiefly associated with intakes of meat, milk and eggs
while blood cholesterol (Fig 14) was directly associated with consumption of dietary fat, meat and animal protein and indirectly with intakes of dietary fiber and legumes.
Further analysis showed that both total and LDL cholesterol (the 'bad' kind) were positively associated with animal protein but inversely with plant protein (Fig 15).
I believe these findings are quite remarkable because only small intakes of animal based foods were associated with significant increases in blood cholesterol and other chronic degenerative diseases. (Keep in mind our earlier finding that animal based foods only comprise less than 20% of total protein intake.) Moreover, the higher the intake of foods of plant matter (as indicated by the fiber and legume associations), the lower the level of blood cholesterol.
The most remarkable finding may be the indication that there appears to be no threshold of plant food effect on reducing the prevalence of these diseases (Fig 16).
That is, the closer a diet is to an all-plant foods diet, the greater and more comprehensive will be the benefit, at least for many, perhaps most individuals.
The social and economic conditions associated with the development of these two groups of disease are quite well-known (Fig 17).
Degenerative diseases of Western countries, which may be better characterized as 'diseases of nutritional extravagance', tend to occur in areas where urbanization, industrialization, and wealth converge. That is, as a society begins to acquire additional capital and resources, people rather quickly begin to consume nutritionally richer diets, particularly diets richer in added fat and sugar and foods of animal origin. This phenomenon has characterized the industrialization of countries around the world throughout history. Wealth can easily feed the emergence of Western type diseases if instant dietary and lifestyle gratification is desired.Independent associations
The second method used to gain insight into these complex diet and disease relationships is to examine specific associations, then to aggregate the findings to see what 'big picture' might be produced (building the whole forest by examining individual trees). A broad variety of relationships have thus far been investigated, as follows.
Breast cancer increases with increasing dietary fat concentration and higher levels of blood cholesterol (Fig 18).
This association may also account for the inverse association of breast cancer with age at menarche. Nutritionally rich diets increase the rate of childhood growth thus causing sexual maturation (menarche) to occur earlier. Many studies have shown that the earlier the age of menarche, the greater the risk of breast cancer later in life. In other words, the fastest rate of childhood growth may not be the healthiest. Breast cancer was also associated with blood testosterone levels (in women) which tend to be elevated with diets higher in fat and foods of animal origin.
Along similar lines (Fig 19), the data from China also showed that body height attained during adulthood is positively associated with increasing intakes of plant protein.
This is an exciting observation because it suggests that it is possible to reach our genetic potential for body height simply by consuming adequate intakes of plant-based foods. It is not necessary to consume animal-based foods simply to reach our maximum body height, as most people around the world have assumed. Moreover, choosing to consume adequate amounts of plant-based foods in order to reach our ultimate body size also has the added advantage of minimizing our risk of the degenerative diseases. This finding was briefly mentioned earlier wherein the impressive increases in attained height for adults from 1950 to 1980 were obtained with very little consumption of animal based foods.
The higher are the blood levels of vitamin C and beta-carotene, the lower are the rates of several cancers (Fig 20).
These antioxidant vitamins are provided almost entirely by plant-based foods.
Dietary fiber may be infinitely complex and its intake can be assessed in many different ways. Associations of multiple fiber constituents with cancers of the large bowel consistently showed lower large bowel cancer when intakes of these fibrous foods were increased (Fig 21).
Oftentimes, people mistakenly assume that certain cancers commonly found in the developing countries, such as with liver and stomach cancers, may be caused by the consumption of plant based foods. This is not true. The reason that these cancers are more common in these relatively poor countries is because of the existence of poverty conditions which predispose to these diseases. Thus, there are much higher proportions of people initially susceptible to these diseases. With liver cancer, it is chronic infection to hepatitis B and C viruses, and with stomach cancer, it is the absence of refrigerated food, thus encouraging the use of highly salted and fermented foods. Such foods enhance the development of chronic stomach 'ulcers' associated with a bacterial organism, Helicobacter pylori. Among people who are predisposed, evidence from this study shows that increasing intakes of foods of plant origin actually reduces the likelihood of disease, both for liver cancer and for stomach cancer (Fig 22).
Dietary associations with cardiovascular disease, of various kinds, have also been examined from multiple perspectives (Fig 23). Apo lipoprotein B, an index of 'bad' cholesterol, is increased with increasing rates of disease.
In turn, this cholesterol level is elevated with increasing intakes of meat and animal protein but is decreased with increasing intakes of legumes, 'light' vegetables, cellulose and plant protein. Again, such data emphasize the health value of plant-based foods.
The dietary and nutritional inferences of these data are many (Fig 24).
A broad array of specific diet-disease relationships in this study indicate considerable health advantage provided by plant-based diets. The likelihood of there being so many associations pointing toward a plant based diet also appears to be highly statistically significant. Moreover, the fact that there are a plethora of explanatory mechanisms and a virtually unlimited number of possible causes makes this suggestion even more plausible.
These findings are especially important in the context of the American experience. Current dietary recommendations suggest decreasing fat intake to 30% of energy as a national guideline. In contrast, these data from China suggest that this recommendation is unlikely to provide much, if any, benefit.Summary of survey results
In summary, two general strategies of analysis were used to examine the more wholistic relationships between diet and chronic degenerative disease in this massive data set. The first strategy combined diseases into naturally associated groups, then sought the principal risk factors for these groups. The second strategy examined multiple individual diet-disease associations, then compared their individual relationships to the consumption of plant and animal-based foods. In both cases, the same conclusion emerges. A diet comprised of a variety of good quality plant-based foods is the healthiest. In addition, there are several more specific corollary conclusions to the main finding (Figs. 25-27).
These findings represent data collected in a 1983 survey of dietary and lifestyle factors combined with data from a 1973-75 disease mortality survey ('China Study I'). Since then, a second survey (Fig 28) of dietary and lifestyle factors was conducted in 1989-90 and these data are being combined with updated, more expansive disease mortality data for 1986-88. This second data set ('China Study II') is even more comprehensive than the first and will enable substantially more robust investigations and interpretations.
These results represent an analysis of a survey undertaken in 1983, just after market reform was being established in rural China. Although this is a one-time sampling, with no trend data (such as for 1950-1980), we can still learn much about the time-dependent disease producing effects of a dietary shift toward a Western type diet, simply by investigating in geographic space what could also be investigated in time. This is what I just presented and the associations are unmistakably impressive. (It should be noted, however, that what is being reported here for China Study I is being strongly supported by early impressions of a second survey of these and further counties in the late 1980's and early 1990's, that is, China Study II.)
Although the biomedical relationships in this study are reasonably clear, the broader societal costs of failing to take seriously this evidence is more difficult to estimate. The main finding from this study, now supported by substantial evidence from other sources, states that future dietary practices ought to minimize consumption of animal based foods. This implies a need for the establishment of appropriate health education programs, while simultaneously minimizing the development of government intervention schemes designed to encourage the production of livestock.
In addition to the biological evidence presented here, it should also be noted that there is supporting evidence from other vantage points as well. First, there are substantial medical treatment costs, although these are very difficult to predict with any degree of certainty. One 'guesstimate' might be drawn from the US experience
Using 1992 dollars, Barnard et al (4) estimated annual direct costs of $29-61 billion merely to treat diseases attributable to meat consumption, an estimate representing approximately 20-40% of total treatment costs for these diseases (Fig. 29).
These figures are roughly in accord with estimates by NIH and other US government agencies suggesting that one-third of all cancers could be prevented by dietary means, although others (5) have suggested upwards of 70% of total cancers could be avoided. This estimate of roughly $30-60 billion might indeed be doubled to $60-120 billion if one takes into consideration 1) the higher proportion of preventable cancers and other chronic degenerative diseases estimated by some, 2) the contribution to disease prevalence by animal based foods other than meat, and 3) the costs of lost productivity. And further, after adjusting for the population size in China and assuming they choose the Western medical model of disease treatment, this figure could well be in the area of $300-600 billion per year for China, although I emphasize that this is a very rough approximation.
There are other societal costs for increasing the consumption of animal based foods as well, especially including the adverse effects to the environment and the wasting of natural resources. Quite apart from these additional costs, however, I believe that the relative inability of China to expand its future feed grain production base to accommodate livestock production is one of the more compelling arguments against the increasing use of animal based foods.
The economy of China has been expanding at an unprecedented pace, growing 57% over the four years of 1992-1995 ((6), cited by Brown), thus making it the fastest growing economy in the world during the 1990s. Individual income has increased by more than one-half during this period, thus permitting them to consume 'higher' on the food chain, that is, consuming diets richer in animal based foods. Much of this increase is comprised of chicken and pork, partly because of the limited availability of land for the grazing of ruminant animals and partly because of the greater efficiency of conversion of feed grains to meat. Beef cattle fed in the feedlot require large amounts of grain and produce one kilogram of beef for every 7 kilograms of grain consumed; one kilogram pork production requires 4 kilograms of grain and one kilogram of beef production requires 2.2 kilograms of grain (7). China, at 37 million tons of pork in 1995, accounts for about one-half of the consumption of the world's consumption, growing at a phenomenal rate of 60% in just 5 years (7). Even though beef consumption lags far behind pork and chicken consumption, it still quadrupled from 1990 to 1995 to an annual consumption level of 4.4 million tons.
These dramatic changes in the consumption of animal based foods in China are ominously reflected in the rapid rise in the use of grain to feed these animals (Fig. 30).
With feed grain production being rather static during the period of 1960 to the late 1970s, use of feed grain has sharply and steadily increased from about 1980 to the present--with no abatement of this increase in sight. The upward inflection around the late 1970s and early 1980s also coincides with the advent of the introduction of the market economy.
Although there seems to be no evidence that this dramatic increase in grain consumption by livestock and poultry is slowing down in China, clearly this must soon be the case. Quite apart from the environmental consequences and economic limitations of producing livestock, grain yield per hectare could soon be reaching its limit, with many observers believing that there is little opportunity for China to meet future grain shortfall by importing grain from elsewhere in the world.
China, although substantially increasing yield per hectare by 4-fold since 1950, is now reaching the yield limit already seen in the US (Figs. 31-32).
The U.S. increased its efficiency of production from 1.65 tons per hectare in 1950 to 4.56 tons in 1990, largely through the use of fertilizers and plant breeding and pest control programs. However, the relative increase per decade has steadily declined each of the last 4 decades to the point where further increases in yield efficiency during the 1990s is not expected to be significant. In other words, the maximum yield potential appears to have been reached because of various climatic and technological resource limitations. China, although lagging behind the U.S. in reaching this limit, also is now (in 1990) at 4.06 tons per hectare. Unless one assumes that much higher yields are achieved with labor intensive methods of production, then China will soon be reaching its limit as well.
The major 'take home' lesson from this research seems to be this. Why, given the overwhelming data showing the health hazards of consuming animal based products, would a country then plan to enlarge or to stress the use of its precious land and water resources with little likelihood of increasing productivity, only to produce the most expensive food thus to produce the most expensive diseases? This hardly seems happiness, as claimed by some.References
1. Chen, J., Campbell, T. C., Li, J. , and Peto, R. Diet, life-style and mortality in China. A study of the characteristics of 65 Chinese counties, pp. 894. Oxford, UK; Ithaca, NY; Beijing, PRC:Oxford University Press; Cornell University Press; People's Medical Publishing House, 1990.
2. Piazza, A. Food consumption and nutritional status in the People's Republic of China., pp. 256. London:Westview Press, 1986.
3. Committee on Diet Nutrition and Cancer. Diet, nutrition and cancer, pp. 478. Washington, D.C.:National Academy Press, 1982.
4. Barnard, N. D., Nicholson, A. , and Howard, J. L. The medical costs attributable to meat consumption. Prev. Med., 24:xxxxx, 1995.
5. Doll, R. , and Peto, R. The causes of cancer: Quantitative estimates of avoidable risks of cancer in the Unites States today. JNCI, 66:1191-1308, 1981.
6. International Monetary Fund International Monetary Fund, Washington, DC. World Economic Outlook, October 1995.
7. Brown, L. R. Tough Choices, Facing the Challenge of Food Scarcity, pp. 160. Washington, D.C.:W. W. Norton & Company, 1996.