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Lessons of a Lifetime: Decades of Scientific Research Show the Power of a Plant-Based Diet

By T. Colin Campbell, Ph.D., with Thomas M. Campbell II

When people hear of scientific information that calls for a radical shift in eating habits, they often react with tremendous skepticism. “We hear one thing one day, and exactly the opposite the next,” they say.

The fact is, there are powerful industries that stand to lose a vast amount of money if Americans start shifting to a plant-based diet.

I understand their confusion. More than 40 years ago, at the beginning of my scientific career, I would have never guessed that food is so closely related to health problems. On the dairy farm where I grew up, my family often started the day with a big country breakfast of eggs, bacon, sausage, fried potatoes, and ham—all washed down with a couple of glasses of whole milk.

A lot has changed since then. Over decades of nutrition research, I’ve come to take a very different view of many foods I once cherished, including meat and dairy products. These lessons came in my work as director of the China Health Study, which The New York Times dubbed “the most comprehensive large study ever undertaken of the relationship between diet and the risk of developing disease.”

My fellow researchers and I determined that plant-based diets are the main reason there are such low rates of heart disease, diabetes, and cancer in certain areas of rural China. In contrast, even small amounts of animal protein-based foods increase the risk of many diseases.

Why hasn’t this important news changed the behavior of most Americans? Why are so many people still eating meals full of artery-clogging eggs, bacon, and sausage? The answer, I believe, lies in how information is created and how it reaches the public.

Because I have been behind the scenes, conducting and reviewing the research that generates health information for more than four decades, I have seen what really goes on. The fact is, there are powerful industries that stand to lose a vast amount of money if Americans start shifting to a plant-based diet. These companies do everything in their power to protect their profits—and that means controlling what the public knows about nutrition and health.

You might think that industry bribes government officials or pays scientists under the table to “cook the data.” But these powerful interests do not usually conduct illegal business. The problems are much more subtle—and much more dangerous. Here are just a few examples:

  • The National Dairy Council and the American Meat Institute have retained prominent scientists to monitor—in effect spy on—research projects that might reduce the demand for meat or dairy products.
  • The Food and Nutrition Board, an expert panel affiliated with the Institute of Medicine, took funding from M&M Mars Candy Company and a consortium of soft drink companies—and then issued a recommendation that a healthy diet can include as much as 25 percent of calories from added sugar.
  • In 2004, the dairy industry began using pictures of celebrity players from the National Football League on cafeteria posters promoting cheese and milk. These materials reach millions of school children, even though dairy foods are now being shown to have many adverse health effects that can last a lifetime.

Most of the confusion about nutrition is created in legal ways and spread by well-intentioned people, whether they are researchers, politicians, or journalists. The entire system—government, science, medicine, industry, and media—promotes profits over health, technology over good science, and confusion over clarity.

Every year, some new product—from vitamin pills to fish oil—is touted as the key to good health. The “health” sections of grocery stores are often stocked more with supplements and special preparations of seemingly magic ingredients than they are with real food. And fad diets, such as the spate of low-carb regimens, come and go.

All this confusion is fueled by narrowly focused studies (often funded or substantially influenced by industry) that are used as marketing tools for certain products.

But the most momentous discoveries in health and nutrition of the past century have not focused on a pill or a fad diet. They have shown how a diet based on the simplest and most natural of foods—whole vegetables, fruits, grains, and legumes—can do what the most powerful tools of medical science cannot: prevent many cases of cancer and stop heart disease in its tracks.

That’s something I wish my family had known when I was growing up. If we had, my father could have prevented the heart disease that killed him and the colon cancer that cut short the life of my wife’s mother.

It is more urgent than ever to show people how to avoid such tragedies. The science is there, and it must be made known. In many cases, the evidence is decades old. We cannot let confusion go unchallenged and watch our loved ones suffer. It is time to stand up, clear the air, and take control of our health.

T. Colin Campbell, Ph.D.T. Colin Campbell, Ph.D., is the Jacob Gould Schurman Professor Emeritus of Nutritional Biochemistry at Cornell University. He is a member of the advisory board of the Physicians Committee for Responsible Medicine. A 1999 graduate of Cornell University, Thomas Campbell is a writer, actor, and two-time marathon runner.


Good Medicine: Tell me the truth about milk

Spring 2005
Volume XIV
Number 2

Good Medicine

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