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The China Study: The Most Comprehensive Study of Nutrition Ever Conducted

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T. Colin Campbell has made a career of challenging the conventional wisdom around nutrition, and this book is the culmination of his work. His integrity, brilliance, and unflinching courage shine through every page.

The main point of this book is that most nutritional studies that we hear about in the media are poorly constructed because of what the author terms "scientific reductionism." That is, they attempt to pin down the effects of a single nutrient in isolation from all other aspects of diet and lifestyle.

While this is the "gold standard" for clinical trials in the pharmaceutical world, it just doesn't work when it comes to nutrition. Given that the Western diet is extremely high fat and high protein compared to most of the rest of the world, studies that examine slight variations in this diet (i.e., adding a few grams of fiber or substituting skim milk for full fat milk) are like comparing the mortality rates of people who smoke five packs of cigarettes a day vs. people who smoke only 97 cigarettes a day.

Campbell's research, which he describes in a very accessible and engaging fashion, has two tremendous advantages over the typical nutritional study. First, there is the China Study itself - a massive series of snapshots of the relationship between diet and disease in over 100 villages all over China. The rates of disease differ greatly from region to region, and Campbell and his research partners (including some of the most distinguished scholars and epidemiologists in the world) carefully correlated these differences with the varying diets of the communities.

It's not lazy "survey research" either - the researchers don't rely on their subjects' memory to determine what they ate and drank. The researchers also observed shopping patterns and took blood samples to cross-validate all the data.

The second amazing part of Campbell's research method is his refusal to accept any finding without taking it back to his lab and finding out how exactly it works. In other words, we discover in The China Study not only in what way, but precisely how, the foods we eat can either promote or compromise our health.

The book is part intellectual biography / hero's journey (although Campbell is always wonderfully humble - there's no trace of self-congratulation, just a deep gratitude for what he has experienced), part nutrition guide (the most honest and unflinching one you'll ever read), and part expose. The final section leaves no sacred cow standing, and names names! From the food industry, to the government, to academia, Campbell calmly reports on a coverup of nutritional truth so widespread and insidious that all citizens should be enraged.

I have a PhD in health education and a Masters in Public Health - and I can honestly say that no book has shaken my worldview like this one. Anyone interested in health - their own, or that of their family, friends, or community - must read this book and share it. Campbell has started a revolution. Skip this work at your own peril.

I love juicy steaks, delicious cheese, and big bowls of ice cream. I love to eat out at nice restaurants. And I really like eating without thinking about the operations and consequences of our dietary industrial complex. But I don't get to enjoy these things any more because I read the China Study. Like Neo in the movie the Matrix, you have a choice, take the blue pill and believe what you want to believe, take the red pill and you will be exposed to the reality of the world we live in. The China Study is the red pill.

This is a fascinating book on the capitalism, politics, and human behavior that drives the food industry. It is also frighteningly insightful into the health consequences of an affluent societies' diet. I am not a scientist so I don't know if this is good science. But I did work ten years ago as a government attorney on the USDA dietary guidelines and was surprised by the political influence and acceptance of what the author would call scientific reductionism. I also worked for a man who lived and worked until he was 100 years old, and he had a dietary regime very similar to that recommended by the China Study: not vegan nor vegetarian, but largely based on plants and whole foods rather than animal based foods. So I found this book very persuasive - in fact, too persuasive. It scared me straight so I eat healthy now and that's good for the long term...but I don't enjoy it like I used to.

This is a fantastic book that's loaded with so much eye opening information, it's the kind of book that I'll read again. I feel if you don't convert to a whole food plant based diet after reading this book, I don't think anything in the world will convince you....the evidence is just overwhelming.


As for my story, I was on statins for high cholesterol for over 6 years....and a moderate to high dose at that. Over the years, my cholesterol kept rising gradually and my total cholesterol was just over 300 and a triglyceride level in the mid 200's without statins. The moderate/high dose statin brought my cholesterol down to the range of high 190's to low 200's. Over the years, I tried to get off the medication and I was told to try to eat a low fat diet, don't eat shrimp, lobster, etc. I went off the statins, tried this diet for several months and none of this helped....actually my cholesterol went higher....I was told it's hereditary, there's nothing you can do, and I should take the statin and that I would be on them indefinitely. Well, after reading the book "The China Study", there's a few paragraphs tucked in this great book mentioning that the major factor causing high cholesterol is eating any animal protein. The only meat I ate at the time was fish and chicken and small portions of it....and maybe beef a few times a year, if that. I have to say I was skeptical and figured what do I have to lose, so I went on a whole food plant based diet (vegan diet)as Dr. Campbell in the book suggests. I started that last November (same time I stopped taking the statins), and I had my cholesterol checked this past summer and was stunned at the result....my total cholesterol went from over 300 without statins, high 190's/low 200's on moderate/high does statin, to 175 without statins on Vegan diet, with good LDL and HDL. I'm guessing next time it's checked it will be even lower. Also, my triglycerides went from the mid 200's to 64! All as a result of just giving up animal products....amazing. Now I wonder....why wasn't I ever given this option by the doctor's I've seen over the years? Even if a person doesn't want to give up animal products completely as I have, why isn't this advice offered as at least an option to a patient.....and let the patient decide? What a concept!

Of course, I feel my cholesterol and triglycerides levels are just the tip of the iceberg on how my health has improved on a plant based diet....the only regret?....I wish I started the vegan diet earlier....I never have had so much energy and just downright have never felt so good....seriously...this is not an overstatement.

As to all the doubters out there with harsh reviews, I say to each is own but ignore the evidence at your own risk. I've seen many of my friends and family sick by what I feel this book has proven by many studies to be nothing more than a bad diet for the most part and most of them are looking for a magic pill to save them....and the old standby argument that it's all genetic doesn't appear to hold much water either....again, proven by studies in the book.

My friend, family, and co-workers know how I eat now and wonder why I want to live forever....that's not the issue....quality of life over quantity of life...isn't this what we should all be after?

When I began reading this book, I couldn't put it down. In the first section, when Dr. Campbell described his own experiments on the effect of milk protein on liver cancer in rats, I just poured through page after page, thinking, "What great science"!

At that point in the book he reported his experiments, their rather dramatic results, was careful to point out the limitations and did not extrapolate. So far, very good.

In the next section he describes the China Study itself. There is also an addendum at the back, which gives more detail about the structure of the study. The foundation for the study was a database collected by the Chinese government during the 1970's. It listed the age and causes of death in each of China's provinces over a certain time period. For the follow-up study ten years later, they chose 67 rural villages and gathered data on details about diet, several markers from blood samples and other factors, on approximately 6000 individuals. He claims to have data on about 350 variables. However, only 57 of the 417 pages in the book are devoted to discussion of The China Study.

The purpose of the study was to try to relate diet and other factors, with the diseases that caused death, especially cancers. His particular interest was about the effect of a purely vegetarian diet. It bothered me that he had undertaken leadership of that follow-up study, with a pre-conceived notion of what he wanted it to show.

At this point in the book, Dr. Campbell began to make very broad statements about the Chinese diet and the benefits of a diet that was devoid of animal protein. This is where I really began to have trouble, because I felt that either the study itself or his description of it fell short of supporting the broad claims he was making.

There's no discussion of things like smoking, environmental pollution and sanitation, all of which plague China.... Even rural China.

Another thing that bothered me was his description of the Chinese diet. It flies in the face of my own observations and experiences during many trips to China and other parts of Asia, over the course of about 35 years.

Meat and seafood are a major staple of the Asian diet. They eat quite a bit of pork, chicken, duck, pigeons, fish, eggs and even snakes, organs and sea creatures that Americans would not eat. They do eat much less animal protein than Americans and always accompany it with lots of rice and vegetables. In that sense, their diet is much better than ours. But it is not vegetarian. Although much of their food is stir-fried in a wok, it is done with vegetable oils. Until very recently, junk food has not been available and it is rare to find beef. So it is a much better-balanced diet than ours.

In years past, during trips to Taiwan, I've been to markets where live chickens & ducks were laid on the ground with their feet tied together. People would either buy them live, or have the merchant slaughter & clean them before their eyes. In one market I saw a vendor selling the blood from snakes he had killed & drained as the people watched. Next day, my hosts took me to a snake-meat restaurant for lunch! (Not much meat & lots of bones.) In back alleys of Taipei, I saw families raising pigeons for food.

Just last year at a Shanghai food market in a very old and traditional neighborhood, the emphasis was on meat and fish. There was a section that sold vegetables & rice, but around the fringes of the central meat market. The displays were open and there was no refrigeration!

As the book proceeded through other chapters, making incessant claims about the preventative and curative effects of an all-vegetable diet, he begins to sound like a 19th century "Snake oil" merchant.

He's a zealot on a soap box. Mind you, HE MAY BE RIGHT. Most of what he says about nutrition has been heard before and is considered by many, to be the Holy Grail of diet. There is certainly a lot of public opinion that red meat, animal fat and highly refined carbs are bad for you. But after the first section, I felt that his science became lost in his rhetoric.

Throughout the early parts of the book, I began to wonder what the meat and dairy industries had to say about all this. He certainly got into that in excruciating detail. Again, to the extreme where unfortunately, he sounded like all the folks at the fringes who claim that "Big business" and "Government" are trying to discredit them. I kept thinking of all the stories of big oil companies buying the patents for a "90 mile per gallon" carburetor, to keep it off the market. (On the other hand, there's Galileo.)

After finishing the book, I went to the Internet to look for critiques. There are plenty! Most are by vegetarians and vegetarian societies, all were having orgasms over the book. Finally I did find a site with some criticisms. Now I'd better mention that this site belongs to an organization that advocates increased consumption of fats and oils. However, the critique of the book was limited to a few specific items and did seem to be based on good science.

I do have some experience with statistical methods of extracting the effect of individual variables from data involving many variables and felt a bit uneasy about the analysis methods while reading Campbell's chapters about the study. This critique pointed out that with 350 variables and just 67 samples, there are not enough samples to establish high (95%) levels of statistical confidence. The best that data structure could accomplish is an "Indication," but not proof.

Actually, Campbell himself does discuss the limitations of statistical methods. His problem is that as the book progresses, he wanders away from "probability" and speaks with "certainty" about too many diverse subjects.

The critic, who had apparently examined the actual 900 page Study report, also claimed that Campbell had ignored data that was counter to his theories and in some cases showed negative results of a vegetarian diet. (That does happen when dealing with probabilities.) He then went on to question the reliability of some of the blood markers that were used. (That part was far beyond any of my knowledge.) Also, the fact that the blood samples of each village were pooled, did enable more markers to be measured, but all data about the variability among individuals was lost.

Another thing that bothered me was that Campbell completely ignored the fact that anthropologists tell us that hominids have been eating meat for about 2.5 million years, apparently with great success. Also, if meat is so harmful, why and how do carnivorous animals thrive?

He tells that cow's milk can cause type-1 diabetes in babies, but that mother's milk is ok. He leaves a gaping hole in his discussion because he doesn't explain the differences between those two types of milk.


So, what is my bottom line on this book?
It is widely accepted that vegetables, especially fresh vegetables, are good for you. No argument there. His early research clearly indicates that there is a threshold, above which animal protein can do some harm. That is intuitively appealing. We Americans do eat much too much meat. But, given the extremely long omnivorous history of mankind, it would seem that a moderate amount of animal protein is an important dietary nutrient.

I feel that Campbell has raised many good points, but his zealotry has taken him too far from sound science. That's too bad. He's hurt his credibility.

The most critic review about this book has misled the readers in one aspect due to his misunderstanding of Chinese life style. This reader criticize the book using his own experiences of his journal to China. He see how Chinese live with his own eyes. The credibility is certainly high, as many Americans who's been to China experience the same. However, what he didn't know is a mistake of anachronism.

As Chinese, I have to point out this mistake. This reader said that Chinese eat a lot of meat or even snakes in the diet. However, this is the phenomenon beginning primarily after 1990s. Snakes eating are the "las Vagas" of the United states, uncommon only in southern part of China (Canton Province). When I was a small child in the 1980s, cancer was rarely heard of. My mother said, when she was a child, she never heard about cancer. We are also wondering why the cases of cancer have ever increased since the 1980s.

Dr. Campell's study is primarily built on the data collected earlier than 2000, when the environmental issues (pollution) were not serious in China.

Therefore, I believe that Dr. Campell's study has strong validity in describing the real situation more than a decade ago.

Please notice that China has changed a LOT in the past three decades. The data would be different today.

If Dr Campbell promotes moral or environmental reasons for going vegan, I'd congratulate him. But he is promoting it as the ultimate diet for humans.

Unfortunately, his advice that we should go vegan is not backed by his own study.

After reading this book, I went to find the actual study (the monograph "Diet, Life-style and Mortality in China") and there were many holes in his hypothesis. There was no correlation between animal protein and disease! I also found conflicting evidence in science journals. He ignored contrary results and left out data that did not support his view.

What I find disturbing is, this book is for the general public and will affect the dietary choices of many people. Most people don't have the time to research these facts for themselves so he takes advantage of that (but if you do, PLEASE go check the information for yourselves before making a decision on removing meat entirely for health reasons). Critical thinking is important.

Anyway, here are the problems with the information in this book:
- This study was an observational study. Problems with studies like these, it doesn't prove causality. Even with that, the results showed no correlation. In fact, it revealed that wheat had a stronger correlation than animal protein intake - which of couse, he left out of the book.

- Casein in milk, he demonstrated, causes cancer. But he also left out feeding SUGAR along with the protein. Sugar has been shown to promote tumor growth. He also didn't mention that casein is not consumed isolated in nature (human breast milk has casein too, should we ban that too?)

- He cited an Indian study that showed rats taking 20% casein with the toxin aflatoxin will develop cancer whereas rats taking 5% casein did not. He just forgot to mention that the rats on the low casein diet died after 6 months. While the 20% casein rats lived for 2 years.

- Protein from plants can also be "complete proteins" if you eat a wide variety of plant foods, based on Campbell's conclusions that complete protein like animal proteins can cause cancer, that must apply to plant proteins as well.

- He says "..there is a mountain of scientific evidence to show that the healthiest diet you can possibly consume is a high-carbohydrate diet". Actually, clinical studies show the opposite - that high carb diets (particularly refined carbs) are bad for diabetics, those who are obese, those with metabolic syndrome and some even show that it's bad for people with heart disease.

- He links total cholesterol with cancer mortality rates. Researchers still have trouble proving high cholesterol is associated with heart disease let alone cancer! (high triglycerides, with high VLDL and low HDL are better indicators than cholesterol. In fact, 50% of people who develop heart disease have mid to LOW cholesterol levels).

- He says overall, the more meat the Chinese consume, the higher the cancer rates. But unfortunately, he left out the county of Tuoli (as demonstrated by Denise Minger) a county with high consumption of meat AND dairy enjoyed ironically low incidences of cancer. The Masai, the Eskimos and even the French with their diets of high fat or dairy and animal protein have good health (low rates of heart disease, low cancer rates, low obesity).

- He believes that the lower rates of cancer among the Chinese compared to Americans must be due to their diet of low animal protein. It is well known that calorie restriction in animals and even in humans can improve health and longevity. This was shown during the world wars when food was rationed, rates of cancer and other diesases fell! The China study was done in the mid 1970's to 1980s - the tailend of the mass starvation of the Chinese before the Mao government loosened its grip on capitalism in the late 80s. For decades prior to the China Study, many counties had little food to eat. Ask any Chinese baby boomer from China and they can tell you how poor they were as children. I've heard stories of people eating roots and bark from trees out of desperation. Meat was highly valued and hard to come by. So the whole notion that the Chinese CHOSE to be vegans is insulting.

- Campbell makes it out as though we should all eat like the Chinese, for disease-free long life. Go find the statistics for longevity of the Chinese and you'll find the average life expectancy of the Chinese is lower than Americans. Yes, you heard right. You can check this yourself online. In fact, the countries with the highest life expectancy are the ones who consume the highest intake of fat and meat. It is a myth that the Japanese centenarians in Okinawa eat a low fat diet. They eat plenty of fish and seafood and their dishes are greasy.

There are more inconsistencies with the information. But you get the point. Before anyone accuses me of being a Campbell basher, think about this: he is SELLING a book, he has his reputation to defend, I don't sell anything, I'm not associated with the meat industry (I dislike them in fact), I bought this book (verified by Amazon) and giving an honest review without vegan-rose-colored-glasses on. I read it with an open mind and came out disappointed and mildly disgusted. Why? Because his suggestions may cause harm to his readers.

I'm not suggesting we go and eat as much factory farmed meat as we want. But free range, organic grass fed meat is healthy - high in omega3, low in omega6, low e.coli count, higher vitamin A and vitamin D in organs.

My review is not an attack on Dr Campbell as a person. I have not made any personal remarks about him. Nor am I attacking veganism or vegetarianism. I think they're morally valid ways to eat that work for some people. What I am attacking is the information, the content and what adverse affects it could have on people's health.

If you're hell bent on giving veganism a go, please take out sugar, refined wheat and Western tofu products from your diet.

I highly recommend this book - read it, check the facts and judge it for yourself.

I was put in a modern medical assembly line to "repair" the effects of modern lifestyle on my coronary arteries. After my angioplasty/drug eluding stent ordeal I got a second opinion (too late). The second Doctor prescribed this book. I read it, believed it, and have lived it for 8 months. I lost 30lbs., my stamina and physical performance has improved dramatically, and my cholesterol has dropped from 270 to 130 and I have gone off some of the drugs. Now whenever someone I love develops symptoms of lifestyle disease, diabetes, obesity or heart disease I give them the book. I thank you Dr. Campbell.

I read most of this book over the past weekend and while I found many of Campbell's points to be persuasive, I was puzzled by some data anomalies that he did not explain. For example, in several charts documenting consumption of animal protein and dairy, the French were rather high on consumption of those foods but did not, according to Campbell's data, suffer as much from the "diseases of affluence" Campbell is addressing. Also, while the Japanese state of health was praised at several points, Campbell never addresses high levels of fish consumption in the Japanese diet. Based only on the data he presented (I am not a nutritional scientist), the case does not seem to be so cut and dried as he presents it. That bothered me.

I first became acquainted with this book by watching a segment this spring (2011) on the Dr. Oz show. I rented the book from the library and read it thoroughly (renewed it a maximum number for times and then decided I needed to own it). My husband and I decided to change our diet and try a vegan life style. We are in our 60's and want to maintain healthy weights (we've lost 35 and 20+ lbs)over the past four months and plan to enter our older years with few health problems. It was amazing to read about all the health situations which can be prevented by eating correctly--even how cancer cells can be turned on and off.

This book provided an excellent understanding of how important it is to eat correctly and the results we will see. My biggest disappointment is that when we share our reasons for our new eating plan with friends and family they aren't more interested in exploring this book and learning about how they can become healthier. Our feeling was, after reading this book, that we couldn't afford to not do this. I think people basically don't want to make changes, even if they will be healthier.

Review of the China Study

I am a scientist, not specifically in the field of nutrition, though I have touched on it as an aside of my main focus, and I know how to research and interpret (correctly!) scientific work. I have read The China Study and the China Project (a publication of the actual data from the study). Normally when reading bad science information I would just shrug it off and move on but thought that there would be people out there that would just take the authors word of the truth of the book, resulting in unnecessary dietary alterations and damage to health all with the aim of trying to get healthier. As such I have written my thoughts on the book - take from them what you will.

The China Study is an attempt by Campbell to promote veganism as a dietary lifestyle through scientific research. Unfortunately the scientific basis of the book if full off misinterpretations, omissions of conflicting data, and conclusions and statements based on unreferenced facts (possibly not facts?). I began reading the book with an open mind but from the outset it was clear that Campbell had one mantra - animal based food is bad, plant based food is good, and this is repeated over and over throughout the book.

Let's first look at Campbells own laboratory studies. In the presence of Aflatoxin, a carcinogen, rats fed a diet of 20% casein, a milk protein, develop cancer while those that are fed 5% casein do not. Okay, I am willing to accept that study on face value. How much casein causes cancer then? In a dose response study Campbell found that 10% casein doesn't contribute to cancer development, but above 10% does. Again, I am happy to accept that. A diet made up of 10% casein contributes to cancer development. How does that apply to humans? After describing a study about nitrosamines and how the dose wasn't relevant to the human population (page 45), Campbell has done the exact same thing with his Casein study. Casein is a milk protein. In 100ml of whole milk, the macro nutrient content is 5.2g of carbohydrate, 3.25g of fat and 3.2g of protein that equals 11.65g of nutrients, the rest of the 100ml mostly made up of water. Milk protein is 80% casein, 80% of 3.2g is 2.56, so out of that 11.65 total, 2.56 is casein which equals 22% of the total. Oh no! Milk will cause us to develop cancer! But don't worry, as long as we get the casein down to 10% we will be safe. How do we do that? Eat 13.95g of anything that is not casein. Pretty easy to do. So as long as we are not living of more than about 50% milk, then we are safe from cancer as a result of the casein in the milk. Do you know anybody that has that much milk? And that is ignoring the fact that casein extracted from milk for the purposes of his study is not exactly a healthy, natural source of protein purely as a result of the chemical extraction.

But hang on, what if other proteins contribute to the development of cancer? Campbell thought that so he investigated gluten and soy and found that neither of them had the same impact as casein. That clearly shows that not all proteins contribute to cancer, and having tested 2 plant proteins and 1 of the many animal proteins, we must therefore conclude that ALL animal proteins lead to cancer and ALL plant proteins do not. Does anybody else see a problem with this? All that we can conclude from these studies is a diet made up of above 10% casein, may contribute to the development of cancer and a diet below 10% casein does not contribute. That is all. Other proteins, both animal and plant, like gluten and soy, may behave differently and unless you have a milk fetish or you are downing large amounts of casein based protein powder (like the rats in the study) then the study is largely irrelevant to your diet or your health.

Before moving on I have one more observation; To test the impact of decreased protein from 20 to 5% they replaced some of the protein with carbohydrates to keep the calories the same. Commenting on the addition of carbohydrate he says "the extra starch and glucose in the low-protein diets could not have been responsible for the lower development of foci because these carbohydrates, when tested alone, actually increase foci development" (page 351). So carbohydrates, which come from plants, increase the development of foci? PLANTS CAUSE CANCER TOO?? Could this be something worth elaborating on or including in a conclusion? No, better not, lets keep that brief mention of carbohydrates causing cancer stuck away in an appendix in case anybody gets the wrong idea.

It is apparent from his casein studies that Campbell has come to the conclusion that "20% casein causes cancer, therefore all animal protein is bad". It is with this mindset that he then set out on the giant study of the China Project, a commendable effort that could have had many beneficial outcomes. Unfortunately, possibly as a result of his previous work, Campbell has gone in with blinders on, and all he can see is animal protein and the negative health outcomes associated with its' consumption. The project itself and the original publication arising from it produced a vast amount of data that provides some interesting insight into health and disease. However, what Campbell has shown in the China Study is but a fraction of the information to be gained from the project. It would require a whole new study (unbiased this time preferably) to go into all the beneficial knowledge we could gain, but I will touch on a few things here.

Campbells main conclusion in the China Study is that all animal protein contributes to disease and all plant protein prevents disease. In the original project, they performed a diet survey over 3 days, analyzing all the food consumed per person in that time. Guess how many of the measured mortality factors (about 50 of them), were associated with animal protein consumption measured from the diet survey. Zero. Zero. Zero. Okay, so Campbell can't have come to his conclusions from there. They also had study participants fill out a questionnaire that included one question on meat consumption. Guess how many mortality factors correlated with that? One type of cancer (naso-pharyngeal or something I think it was). An example of some of the many other inclusions in the questionnaire are canola oil and potatoes (not sweet potatoes) which both had a number of positive associations with the development of different types of cancer. Apparently that wasn't worth mentioning in the China Study. Speaking of oil, Campbell makes reference to %fat in the diet being a good indicator of animal protein consumption, despite the fact they clearly use enough canola oil (a vegetable fat) to measure in the study.

So a 3 day food consumption survey shows no association between animal protein and mortality and a questionnaire shows an association between meat and one of many cancers measured. From where can Campbell come to his evil animal protein conclusion then? They also took plasma samples and measured them for blood biomarkers of animal protein consumption. These biomarkers, listed in the references for chapter 4 #39 are "plasma copper, urea nitrogen, estradiol, prolactin, testosterone and, inversely, sex hormone binding globulin, each of which has been known to be associated with animal protein intake from previous studies". No mention of these previous studies of course. So the associations with most of those biomarkers and mortality rates are dubious, and the only biomarker statistically associated with cancer mortality is copper. Many places show food sources of copper and I went to [...] find the best sources of copper. The best? Calfs liver. The next 40 best? All from plants. 42 and 43 are shrimp and venison, the only other animal source in the list on the site. So for copper to be a biomarker of animal consumption then the participants in this study must be eating a lot of calf liver and avoiding a lot of vegetables. Sound realistic?

So from an association between blood biomarkers, the only real one being copper, and cancer mortality, Campbell has concluded that animal protein gives you cancer, despite the fact that the majority of dietary sources of copper are actually from plant sources. So that basically leaves Campbell with no actual evidence between animal consumption and mortality as a result of the original China project.

A final note. In his eating right section Campbell says supplements are bad (principle 2). Principle 3 then says "there are virtually no nutrients in animal-based foods that are not better provided by plants"(page 230), but over the page he says plants are not a good source of vitamin B12 and you probably should take a supplement. What? Then in the how to eat section on page 242 he says "the findings from the China Study indicate that the lower percentage of animal-based foods that are consumed, the greater the health benefits-even when the percentage declines from 10% to 0% of calories". As I've clearly shown, the China Study does not show this, and his own study with Casein proved that there was no benefit in eating less then 10% of your diet from Casein.

Clearly Campbell is a vegetarian, as he states in the book, and promoting vegetarianism is his main goal, which he tries to back up with scientific research that actually disagrees with him, but that he has interpreted in a way that makes it agree with him. Bad science, bad book and definitely bad recommendations as far as health. While I'm not saying go out and live on animal products alone, I don't think you should stop eating them, especially because they are tasty, but even if only for a natural source of vitamin B12.