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Is Animal Protein Good for You?

T. Colin Campbell, Ph.D., has been at the forefront of nutrition research 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. T. COLIN CAMPBELL: I like to suggest a “whole foods, plant-based diet.” By that I mean whole vegetables with lots of colored vegetables included. Whole fruits, whole grains, and legumes, as close as possible to the way they have been prepared by nature, without adding a lot of oil or fat or sugar. I also believe it is optimal to consume much of our food in its raw form. By this I am talking about salads, fresh fruits, and fresh vegetables. I'm not a proponent of a 100 percent raw-food diet for a variety of reasons, but I believe that an abundance of raw foods is a really smart way to go.

JOHN ROBBINS: What is the relationship between animal food and the alkalinity or acidity issues in the body?

DR. T. COLIN CAMPBELL: Well, animal food in general creates a sort of metabolic acidosis that can drop the body's pH one or two tenths of a unit. That can make quite a difference. The animal foods can create a more acidlike environment, which has been shown to have some significant effects on enzyme activities.

JOHN ROBBINS: It seems to me that a great number of people are suffering from some subclinical levels of acidosis. If someone is wanting to alkalize their system, how would you suggest they go about that? What foods should they eat? Are there certain activities they should undertake or avoid?

DR. T. COLIN CAMPBELL: I don't think we really have good, solid research on that question. But what we do know is that plant foods will create a more alkaline environment in our bodies and the big contribution to acidification is simply animal-based foods.

I was asked recently for my view on the use of alkaline water and some of these products that are supposed to add alkalinity in the human body. I really am sorry, but I can't give a good answer to that. There may be some research, I just haven't been familiar with anything that convinces me yet. I am open to the possibility of alkalizing foods or maybe alkalizing water, but I don't think we have enough data to know for sure.

JOHN ROBBINS: It seems that you are saying that the central thing to do is to derive as much of our nutrients, our proteins, our vitamins, our phytochemicals, our fats, and our carbohydrates from plant sources as possible.

DR. T. COLIN CAMPBELL: Absolutely. I think a lot of the time in the field of medicine and nutrition research in particular, we get caught up in the details rather than thinking about the big story. I think the really big story is just getting some wonderful vegetables and fruits and grains in their natural and whole state, and learning how to use them and adapt to the taste of them.

JOHN ROBBINS: You have been a researcher, a scholar, and a scientist for more than forty years. You went to China and conducted the most comprehensive study of human nutrition in world history. Now you and your son have written about what you learned in The China Study, which is a runaway bestseller. You have come to be on the front lines, challenging the prevailing nutritional dogma. How is that for you?

DR. T. COLIN CAMPBELL: It has been gratifying and honestly somewhat surprising to see the story of The China Study go as far as it has. I was always quite confident of what we had written and what I had done. But I did not know how the public would respond. Some people are persuaded by the time they get to chapter three, where I am talking about protein and cancer. Other people are persuaded by the last third of the book, where I talk about my twenty years' worth of experience on National Policy Boards on food and health and some of the insights I gleaned along the way.

JOHN ROBBINS: You are running up against government, medicine, corporations, and the media, all of which have at times concentrated on profits at the expense of health. Together they have created a level of confusion about nutrition and have at times stifled and even attempted to destroy viewpoints that challenge the status quo. You, yourself, were almost expelled from a committee of scientists because you dared to suggest that there might be a link between diet and cancer. Where do you find the strength to continue working so hard despite all the obstacles, discouragement, and resistance that you encounter?

DR. T. COLIN CAMPBELL: Well it took many years for me to get enough confidence. Honestly, your work, as well as the work of Dr. John McDougall and others, helped to give me courage and inspiration. All of a sudden it occurred to me that I wasn't standing alone. I was just contributing my part. I get a lot of strength from being part of this community.

We have to go in this direction, because now we have enough evidence from the laboratory, from the field, and even from certain philosophical and environmental resource perspectives. We have enough evidence now to demonstrate it. I have taken my hits and I am sure you have too, some of them pretty serious. But I keep trying to look past them, because this is a story worth telling.