After reviewing the online debate regarding Dr. Campbell’s studies, I can only reach one conclusion: I’ve certainly stepped into a can of worms with my review of The China Study. A simple search is all it takes to find page after page of highly charged debate about Dr. Cambell’s methods, conclusions and personal character. It might have been smart, from the moment I found those worms wriggling around my ankles, to back quickly and quietly away and say no more about it.

Most likely, no one would have taken me to task. But I’ve never been inclined – whether in work or in life – to avoid an issue just because it’s messy. The fact is, life is messy. That may be the one fact I can get away with publishing that no one can dispute.

We deify science because we imagine that all that messiness has been controlled for and all the competing factors have been taken into account. So the results are quantified, qualified, peer-reviewed and packaged into handy conclusions that we can publish in our textbooks and pamphlets and which now take on the weight of “truth.” But is this really truth, or is it convenience? And what price do we pay when we privilege convenience over a sincere, soul-searching attempt to understand who to trust and how to live?

The main critique of Dr. Campbell is that he is a messy scientist. Some critics claim that his citations do not precisely back up his conclusions, or his conclusions are too broad, or his associations are not significant, or were not arrived at in a precise manner. In response, Dr. Campbell points out that these online critics lack the necessary credentials to evaluate his studies. For the most part, they have no scientific training, experience in nutritional science or publication of original research. He points out that the National Institute of Health subjected his studies to frequent reviews at multiple levels of oversight over 27 years while evaluating whether or not to continue funding them. Even if their critiques were valid, he suggests that they are missing the forest for the trees. In other words, he points out that his own studies form only a small part of the overall picture, and that many prominent research scientists in the field of nutrition have reached similar conclusions. He calls on readers to consider the “weight of evidence” rather than getting hung up on the details of a particular study. (1)

I’m not in a position to mediate the disagreements between Dr. Campbell and his critics. He may be a messy scientist, or he may have hit a nerve that is causing people to pick apart his studies in a way they wouldn’t bother with other studies that arrive at less-challenging conclusions. However, what intrigues me is that Dr. Campbell doesn’t just challenge the main assumptions of nutrition (namely, that animal protein is the highest quality protein and necessary for human health) but that he challenges the very basis of nutritional science itself.

In a debate with Dr. Loren Cordain about the role of protein in nutrition, Dr. Campbell explains how his philosophy of nutrition differs from what has traditionally been practiced. He points out that ever since the Renaissance, precision has been the guiding principle of science. He acknowledges that the ability to precisely measure, calculate and assemble the components of physical (i.e. non-living) systems has produced great advances in technology. However, he claims that the same cannot be said for biomedical (i.e. living) systems, which are far more complex and information-dense than inert, physical systems. In the field of nutritional science, the search for precision is misguided because “we cannot construct biological complexity that is faithful to the natural order of things, no matter how precisely we measure and know the component parts of these complex systems.” (2) This is because the component pieces of biological systems are constantly interacting and influencing each other in ways that we can’t predict, but only observe.

A research scientist, in his quest for precision, may precisely measure and administer a nutrient, he may precisely measure and control for all the variables he sees, and he may precisely measure and report the outcome. But, if he never steps back to consider the whole organism, his results may be either precisely wrong or precisely irrelevant because the subjects of his research were interacting and producing effects he never took into account.

Dr. Campbell challenges the assumptions we make about science and truth when he says “by exaggerating the importance of precision in biomedical research, we also err in other ways. That is, we too often misinterpret the concept of precision as perfection. Assuming more perfection implies more ‘value’ and for some scientists, precision may mean invincibility and absolute truth (or might we say, ‘arrogance’?)”

Dr. Campbell isn’t claiming that science is worthless or that we can’t apply standards to research. Rather, he concludes, “Biomedical and nutritional research should be conducted within a paradigm that is substantially different from the contemporary, traditional paradigm. We must strive to develop hypotheses, to organize research studies, and to interpret and apply results that acknowledge biological complexity and that describe cause-effect relationships cognizant of that complexity. From this perspective, observations on the component parts, however precisely measured, only represent relative truths, not absolute truths. Moreover, we should stress research that is observational, comprehensive and representative of real life conditions.”

He goes on to explain that this “means that deciding which groups of foods to consume is far more important than deciding what levels of individual nutrients should be consumed. It means that priority should be given to the search for collective disease and health outcomes that may respond to the same diet and lifestyle conditions….Most importantly, it means using ‘weight of evidence’ – all evidence – as the standard method of determining the reliability of cause-effect hypotheses.” (3)

When we go to the store with fifteen minutes to pick out a meal, we don’t necessarily need to know how many units of vitamin C are contained in a particular food and what the impact of that vitamin C is on our liver function. We need to know the basic impact of the whole food on our whole body. Are carrot sticks healthier than mozzarella sticks? Are beets better for us than wings? Dr. Campbell is proposing that the only way to make accurate predictions about diet and health is to re-evaluate our ideas about science, and to start conducting broader research with an emphasis on real-world observation. Dr. Campbell documents the beginning of his attempts to conduct this kind of research in The China Study. Whether he has been successful or not is a matter of debate. But, to my mind, his aim is a good one and I hope future scientists will take up his challenge and expand upon it.

  1. The primary critiques of Dr. Campbell come from author's associated with the Weston Price Foundation. Their objectivity has been questioned because the primary purpose of WPA is to promote a diet high in animal fat. For a more objective analysis, follow the link above to Harriet Hall's critique at Science Based Medicine. In the comments you will find an ongoing (and increasingly off topic) debate about her citation of a Weston Price author, but if you scroll down far enough you will find a response from Dr. Campbell himself, under the pseudonym tcc1.
  2. Campbell, Dr. T Colin and Dr. Loren Cordain. March, 2008. The Performance Menu: 27.
  3. Campbell, Dr. T Colin and Dr. Loren Cordain. March, 2008. The Performance Menu: 28.