for more than forty years. His legacy, The China Project, is the most comprehensive study of health and nutrition ever conducted. Dr. Campbell's academic credentials are extraordinary. He is the Jacob Gould Schurman Professor Emeritus of Nutritional Biochemistry at Cornell University. Dr. Campbell has more than seventy grant-years of peer-reviewed research funding and more than 300 research papers on his resume. He is coauthor of the bestselling book, The China Study: Startling Implications for Diet, Weight Loss and Long-term Health.
Dr. Campbell grew up on a dairy farm. Over the decades, his research has led him to believe that dairy products, and animal protein in general, are having a profound impact on human health that is not at all what most of us imagine. His decades of research have brought him to some startling conclusions.
JOHN ROBBINS: Dr. Campbell, like you I grew up eating a lot of dairy products. How has your research impacted your personal dietary choices?
DR. T. COLIN CAMPBELL: I was raised on a dairy farm and milked cows until starting my doctoral research more than fifty years ago at Cornell University in the animal science department. Meat and dairy foods were my daily fare, and I loved them.
When I began my experimental research program on the effects of nutrition on cancer and other diseases, I assumed it was healthy to eat plenty of meat, milk, and eggs. But eventually, our evidence raised questions about some of my most-cherished beliefs and practices.
Our findings, published in top peer-reviewed journals, pointed away from meat and milk as the building blocks of a healthy diet, and toward whole, plant-based foods with little or no added oil, sugar, or salt.
My dietary practices changed based on these findings, and so did those of my family.
JOHN ROBBINS: What did you discover?
DR. T. COLIN CAMPBELL: In human population studies, rates of heart disease and certain cancers strongly associate with animal-protein-based diets, usually reported as total fat consumption. Animal-based protein isn't the only cause of these diseases, but it is a marker of the simultaneous effects of multiple nutrients found in diets that are high in meat and dairy products and low in plant-based foods.
Historically, the primary health value of meat and dairy was touted to be a generous supply of protein. But therein lay a Trojan horse.
More than seventy years ago, for example, casein (the main protein of cow's milk) was shown in experimental animal studies to substantially increase cholesterol and early heart disease. Later human studies concurred. Casein, the properties of which, it's important to note, are associated with other animal proteins in general, also was shown during the 1940s and 1950s to enhance cancer growth in experimental animal studies.
Casein, in fact, is the most “relevant” chemical carcinogen ever identified; its cancer-producing effects occur in animals at consumption levels close to normal—strikingly unlike cancer-causing environmental chemicals that are fed to lab animals at a few hundred or even a few thousand times their normal levels of consumption. In my lab, from the 1960s to the 1990s, we conducted a series of studies and published dozens of peer-reviewed papers demonstrating casein's remarkable ability to promote cancer growth in test animals when consumed in excess of protein needs, which is about 10 percent of total calories, as recommended by the National Research Council of the National Academy of Sciences more than seventy years ago.
JOHN ROBBINS: Do you see any beneficial role for bovine dairy products in the human diet?
DR. T. COLIN CAMPBELL: I see no redeeming value in consuming dairy products from a nutritional perspective. The dairy industry has long promoted the myth that milk and milk products promote increased bone health—but the opposite is true. The evidence is now abundantly convincing that higher consumption of dairy is associated with higher rates of bone fracture and osteoporosis, according to Yale and Harvard University research groups.
Plant-based foods turn out to have plenty of calcium along with far greater amounts of countless other essential nutrients (such as antioxidants and complex carbohydrates) than meat and dairy.
The dairy industry has promoted its products as a good source of high-quality protein. But higher-protein diets achieved by consuming animal-based foods increase the risks of cancer, cardiovascular diseases, and many similar ailments.
Protein consumed in excess of the amount that we need, and most of us do consume more than we need, actually has some pretty serious consequences.
I wouldn't have expected to see this because, like you John, I was raised in a dairy family. I always believed that the good old American diet was about as good as it gets. And subsequently I went off to graduate school and actually did my doctorate dissertation expecting the research to prove my beliefs to be correct. I never imagined that we would find the things we did find. It turns out that protein from cow's milk is also a pretty potent inducer of higher cholesterol levels, atherogenesis which is the forerunner for cardiovascular disease, and a number of other sorts of illnesses.
JOHN ROBBINS: It would seem that cow's milk is nature's most perfect food for a baby calf—who has four stomachs and is a ruminant animal that will gain about 200 pounds in its first year. I guess if a human infant has those characteristics, it would probably be the right food for that child. I think the cultural belief system that holds dairy products as exemplary is causing a lot of damage to people. The mainstream belief is that the saturated fat in dairy products and other animal foods can contribute to heart disease. But, your studies and many others indicate that many of the chronic diseases found today result from the consumption of animal protein.
DR. T. COLIN CAMPBELL: Some of the most compelling evidence of the effects of meat and dairy foods arises when we stop eating them. Increasing numbers of individuals resolve their pain (arthritic, migraine, cardiac) when they avoid dairy food. And switching to a whole-food, plant-based diet with little or no added salt, sugar, and fat, produces astounding health benefits. This dietary lifestyle can prevent and even reverse 70 to 80 percent of existing, symptomatic disease, with an equivalent savings in healthcare costs for those who comply.
This treatment effect is broad in scope, exceptionally rapid in response (days to weeks), and often, lifesaving. It cannot be duplicated by animal-based foods, processed foods, or drug therapies.
By contrast, any evidence that low-fat or fat-free-dairy foods reduce blood pressure is trivial compared with the lower blood pressure obtained and sustained by a whole-foods, plant-based diet.
Based on the scientific evidence, and on the way I feel, I know beyond any doubt that I am better off for having changed my diet to whole and plant-based foods.
JOHN ROBBINS: We have compelling evidence that many of our chronic and devastating illnesses can be prevented with improved nutrition. But for someone who actually has cancer, do you see diet as having a role in effective anticancer treatment?
DR. T. COLIN CAMPBELL: Quite possibly. For a long time, we talked about nutrition as it might relate to the prevention of future problems. But now in recent times we have been seeing that the same diet that tends to prevent future problems can also be used to reverse and treat certain illnesses after they are present. With heart disease and Type 2 Diabetes, the role of diet in reversing disease once it is present is very clear. With cancer, the preventive role of nutrition is solidly documented. But for reversal of existent disease in the case of cancer, the evidence is not as strong, although it does exist.
We need more good-quality research on the question concerning the effect of diet, and protein in particular, on the development of cancer. But unfortunately in our medical community, that kind of research has not really been done very well. The reason is that doctors have generally not been schooled in nutrition and they are extraordinarily reluctant to admit that this is a good idea.
JOHN ROBBINS: If you could design the diet that our governments would advocate and support, based on what is healthiest for people, what would the diet look like?
DR.