The China study: The most comprehensive study of nutrition ever conducted
The China Study: by T. Colin Campbell
The China Study is a book written by T. Colin Campbell PhD and his son, Thomas M. Campbell II. Data used to substantiate the information presented in The China Study comes from Dr. Campbell's part in a 20-year study that was done in cooperation between Cornell University, Oxford University, and the Chinese Academy of Preventive Medicine and Dr. Campbell's own 40 years of biomedical research. He has been funded for an equivalent of 70 “grant-years” of peer-reviewed research and has authored more than 300 research papers in addition to writing The China Study.
From 1958-1961, T. Colin Campbell was working on his PhD in biomedical research by researching ways to improve the supply of high quality protein by growing cows and sheep more efficiently. He had grown up on dairy farm and consumed meat and dairy as part of every meal, as most of us do, from the time he was a child. Meat had protein which the body needs, dairy had calcium which makes our bones stronger. These are things he had always heard stated as fact, and he had dedicated his professional career to studying. After graduating from Cornell, he was hired by MIT where, over the next few years, he and his team extensively researched and successfully isolated the carcinogenic substance known as dioxin (used to make Agent Orange). They also studied another toxic chemical called aflatoxin, a mold found in corn and peanuts.
In 1967, based on his work at MIT, he was asked to be the Campus Coordinator for a research project in the Philippines. This study would eventually span ten years, and the results of which would change the way he looked at protein for the rest of his career. There were two major health issues in the children around Manila and Cebu, the first alarming concern was malnutrition, the second was a massive rise is liver cancer among very young children- some as young as four years old.
While looking into peanuts as a possible solution to the malnutrition problem, he found that local peanut growers were sorting out the good peanuts for “cocktail” nuts, and the moldy peanuts were being made into peanut butter. Local children, especially in Manila, were eating the peanut butter and being exposed to high levels of aflatoxin. Then, while looking into the liver cancer issue, he found that the children under ten years old who had been diagnosed with cancer were not from the malnourished families, but rather they were from the best-fed families, whose diets most closely resembled a standard diet here in the U.S. This went directly against what he had previously believed, that liver cancer was caused by inadequate protein intake.
While his research was going on in the Philippines, he was made aware of a study that had been done in India with aflatoxin and its correlation to liver cancer. There were two groups of rats that were each fed equal amounts of aflatoxin, then one group was fed a diet containing 20 percent protein, while the other group was fed a diet of 5 percent protein. By the end of the test, every single rat in the 20 percent group had liver caner or its pre-cursor lesions.
Shockingly, none of the rats eating the 5 percent protein diet had developed liver cancer! “It was not a trivial difference; it was 100 percent versus 0 percent,” he says in the book. It was a major turning point for his career, and he decided he must pursue the true connection between protein and cancer to whatever end it might lead him, even though he knew he would be going against a well established status quo.
Back home, he received more grants, and began work verifying the results from India. Over the next few years he did exactly that and much more! Before he goes into the results of these new rounds of research, Dr. Campbell explains the three stages of cancer: initiation, promotion, and progression. “To use a rough analogy,” he says in the book, “the cancer process is similar to planting a lawn. Initiation is when you put the seed in the soil, promotion is when the grass starts to grow, and progression is when the grass gets completely out of control, invading the driveway, the shrubbery and the sidewalk.”
When we are exposed to a carcinogen, (like aflatoxin, dioxin, or any other caustic chemical) it is absorbed into the blood and then transported into various cells. Once in a cell, the carcinogen is then metabolized by an enzyme, which then mutates into a dangerous byproduct that attacks the cells DNA. Much of the damage done to the DNA structure is naturally repaired by our immune system, but when the cell multiplies before the damaged DNA is repaired permanently, then it becomes a cancerous cell. Now, every time this cell replicates/multiplies, it creates identical, cancerous ‘daughter' cells. That is the initiation process of cancer and the entire process can take as little as minutes! Anybody who has been exposed to a carcinogen (everybody) has cells that have gone through this primary initiation process.
It's the promotion process that decides how many cancerous daughter cells cluster and form detectable tumors. This is the slow process that takes months or years. Like the lawn in the analogy, for grass to grow it needs water, sunlight, and nutrients to promote growing success. Cancer cells have needs too. Things that help cancer grow are called promoters. Things that hinder the growth of cancer cells are called anti-promoters. What is so fascinating about the promotion stage is that it is completely reversible! Like anybody who has planted a new lawn knows, things can go horribly wrong and the entire lawn can die out. Well, in the case of cancerous cell growth, ‘killing off the lawn' is exactly what you want to happen. If you starve the cancer cell of the nutrients it needs during the promotion stage, you can not only stop the cancer from growing and spreading, but you can reverse the process and revert the cell back to normal, although the cell will always carry a ‘memory' and will be more susceptible to becoming cancerous again in the future.
The final stage in the process is progression. Far into the progression you hear the word metastasize. This means that cells from the initial cancerous tumor on a specific organ (like the lungs or liver) have spread out and taken over the neighboring organs and tissues. And when this outbreak goes beyond management the very final stage occurs: death. We all know somebody who has died from cancer, so some of these stages and concepts are probably vaguely familiar.
Taking these three stages into consideration, Dr. Campbell focused his attention on the second stage: promotion, because this stage was the slowest and held the most opportunity for reversal. He replicated the study done in India and was able to discover the many specific ways that a low protein diet reduces the production of tumors. The five mains mechanisms for the reduction of tumor growth are: less aflatoxin initially enters the cell, cells multiply more slowly, multiple changes occur within the enzyme complex to reduce its overall activity, the quantity of critical components of the relevant enzymes are reduced, and less aflatoxin-DNA adducts are formed.
Dr. Campbell says, “From our extensive research, one idea seemed to be clear: lower protein intake dramatically decreased tumor initiation.” He explains that the human body needs a diet of about 10 percent protein to be healthy (a range of about 8-12 percent depending on body weight). As soon as protein intake exceeds the needed amount, enzyme production increases exponentially; so as far as protein intake goes, the more is not the merrier!
Up to this point in all his experiments the protein Dr. Campbell's group had been using was casein, which makes up 87 percent of cow's milk protein. The next set of questions that he needed to answer were whether is matter which type of protein was been consumed. Next they replicated all the 5 percent-20 percent tests, but this time they used different types of protein on each sets of rats, both animal proteins from fish and livestock, and plant proteins like gluten and soy.
What resulted was nothing short of spectacular! The rats now being fed animal proteins had the exact same reactions as the casein rats, diets in the 10-20 percent ranges all developed liver cancer or the beginning stages of increased foci development. On the contrary, none of the rats in the 10-20 percent plant based protein diet groups developed increased foci production or tumors, even when given increased aflatoxin doses!
In the next set of experiments he branched out from liver cancer and into other types of cancer and disease to see if these results would hold. First they worked with hepatitis-B because chronic HBV patients have a 20-40 percent increased risk of developing liver cancer. Again, when the casein diets exceeded about 14 percent the viral infection began to turn cancerous. In 1982 The University of Illinois Medical Center in Chicago research the connection between mammary (breast) cancer and casein and also had the same results; increased casein intake promoted mammary cancer growth in infected subjects along the same percentages. At this point he had all the information he needed to move beyond rat testing. It was clear, excessive animal protein consumption promoted cancer in rats.
Now he needed to take these results to the next level: human testing. But how could he possibly organize a study large enough to completely verify his finding? In 1980 the answer to his need walked through the door of his lab in the form of a Chinese scientist named Dr. Junshi Chen. In the early 1970's the first premier of the People's Republic of China, Zhou EnLai, was dying of cancer. He helped initiate The China Health and Nutrition Survey, the largest survey ever completed to date (and it is still ongoing).
With 650,000 workers and the best medical researchers available, they collected data from 880 million Chinese citizens. Not only are the sheer quantity of people questioned important, but an additional important factor to understand is that 87 percent of people living in China at that time were (and generally still are) genetically similar, from the Han heritage. Not only would the findings of this alliance result in knowledge regarding the connection between diet, lifestyle, and cancer, but it would also subsequently disprove the idea that cancer is largely the result of ones genetics.
Dr. Chen brought the China Atlas. This was the primary result from the initial massive survey of 96 percent of the entire Chinese population. The Atlas made one thing crystal clear, cancer in China was geographically localized. In many rural areas, cancer was almost non-existent. While urban areas and small pockets of rural areas were experiencing dramatic increases in cancer and disease. The next natural step was to gather more data. With the help of the authors of the Cancer Atlas Survey, Dr. Campbell, Dr. Chen, and a team of world class researchers went to China.
The team selected 65 rural to semi-rural counties to gather data from 6,500 people, testing 367 variables. They administered blood tests, urine samples, and measured everything the families ate over three day periods. From the Cancer Atlas they had access to disease mortality rates on more than four dozen kinds of diseases, including cancer, heart disease, and other infectious diseases. In the end they discovered “more than 8,000 statistically significant associations between lifestyle, diet, and disease variables.”
Let's compare an average diet in China to its counterpart diet in America. The average American eats 15-16 percent of our total calories from protein and 80 percent of that is typically from an animal protein source. The average Chinese person in the study typically ate only 10 percent of their total calories from protein and only 10 percent of their total protein, on average, came from an animal source.
Strangely enough, the total calories in the low protein (33g/day) diets were higher than the high protein (91g/day) diets. In China they ate about 650 more calories per day, but because the protein was primarily plant based and not animal based the fat percentages were only 14.5 percent in China versus 36 percent in the U.S. diet. The last two major differences between the two diets were total iron and fiber intake. In China they ate 33 g/day fiber and 34 g/day iron, while in the U.S. they only ate 12 g/day fiber and 18 g/day iron.
Later they looked into blood cholesterol levels and found that the average person in China had 127 mg/dL level while the U.S. average was 215 mg/dL. In some parts of China there were women with levels as low as 80mg/dL! Sadly, in the U.S. there were levels as high as 290 mg/dL. Having your cholesterol levels checked is a common practice in the U.S., and you may know your own current levels. The research team discovered that there was a significant correlation between blood cholesterol and cancer; people who reduced their blood cholesterol from 170 mg/dL down to 90 mg/dL had an exponential reduction in cancers of the liver, rectum, colon, lung, breast, leukemia, brain, stomach, and throat.
And that's just cancer
There is, of course, one disease that kills more people every day, week, and year than cancer, and that is heart disease. While some of Dr. Campbell's finding may seem controversial, nobody argues that reducing blood cholesterol levels prevents and reduces your risk for heart disease. In all their tests, and as a result of their massive data collection endeavors, Dr. Campbell and his team found that animal based proteins raised bad blood cholesterol levels, while plant based proteins lowered levels.
The conclusions are clear: nutrition has everything to do with health. The science is unmistakable and indisputable. So, why is it very likely that you haven't heard this information before? Why aren't these facts plastered on every front page? Over a million people each year die from heart disease or cancer, and it is sad, preventable, and the medical costs associated with these diseases are extremely high.
If there is even the slightest chance that simple, cheap changes to our daily diets can make massive improvements in our health and possibly prevent hundreds of thousands of deaths a year, why doesn't everybody know this information? Some of the most shockingly revelations found in the second half of The China Study answer those questions and many more. For instance, did you know that the National Dairy Council spends around 150 million dollars a year on advertising? “Got Milk?” Sound familiar?
Another frightening fact that Dr. Campbell brings to light regards nutrition education given to our medical doctors. As early as 1985, the United States National Research Council has known that nutritional programs in US medical schools were “largely inadequate to meet the present and future demands of the medical profession.” Recently things have gotten even worse.
As of 2003, educational curriculum (developed by large corporate interests such as The Dannon Institute, Egg Nutrition Board, National Cattlemen's Beef Association, National Dairy Council, Nestle Clinical Nutrition, Weyth-Ayerst Laboratories, Bristol-Myers Squibb Company, Baxter Healthcare Corporation, and more) being taught in over 112 medical schools in the U.S. is given for free to the institutions and is, in many cases, the entire sum of all nutritional education aspiring doctors will be given during their medical school training. Does it benefit these groups to keep this information away from the public eye?
So what should we eat? As a result of his years and years of research, Dr. Campbell strongly advocates the importance of eating a Whole Foods, Plant Based diet because it is rich in fiber, iron, good fats, carbohydrates, minerals, and micro-nutrients that can't be replicated in a lab. A diet with as low animal protein intake as possible will greatly reduce your risk for all kinds of cancer, heart disease, auto-immune disease, diabetes, osteoporosis, obesity, and many other “diseases of affluence”. Also, human beings need sunlight and we are not getting enough of it. Sunlight is the best source of vitamin D available, and vitamin D is responsible for, among other things, converting calcium into usable food for the bones and body. So if you're in-taking plenty of calcium through plants, but aren't getting sunlight, then you aren't getting the full benefits from the calcium.
One last important idea to note; no general vitamin supplement can replace the benefit of eating fresh whole foods, because eating the actual fruit or vegetable will, in addition to giving you the specific mineral you want, will also contain fiber and other crucial micro-nutrients that are non existent in any other form. He does say that the one exception to the vitamin supplement rule is vitamin D supplements simply because sunlight exposure is so vitally important.
If you are unable to get adequate (15 minutes) sunlight each day, then taking a vitamin D supplement is a good idea. Spices and herbal supplements are not in the same category as the general, lab-made, synthesized vitamin pills. Many herbs and spices (such as turmeric, cinnamon, red clover, cumin, garlic, onion, or many more) have priceless micro-nutrients and minerals that are medicinally viable in their dried, powdered form.
This is just the tip of the iceberg as far as nutrition goes. In addition to Dr. T. Colin Campbell and his son Thomas M. Campbell II, several other (many ivy league graduated) doctors have turned to advocating a whole foods, plant based diet. Doctors such as Dr. John McDougall, Dr. Caldwell Esselstyn, Dr. William Castelli, and Dr. Ornish just to name a few. Collectively they have gathered dozens of books worth of data, figures, articles, and more to back up their nutrition claims.
For More information, check out these links:
Get the Book: The China Study
The China Study Website: http://www.thechinastudy.com/
The China Health and Nutrition Survey: http://www.cpc.unc.edu/projects/china
Dr. John McDougall and his work on how to reverse Heart Disease: http://www.drmcdougall.com/
Dr Ornish's webpage: http://www.ornishspectrum.com/