I know this was all over the blogosphere yesterday but I think it’s important enough for a repost.
One thing I can count on every time I write an article extolling the health benefits of animal products is someone sending me an email or posting a comment like this:
I think you’re absolutely wrong. You should read: The China Study, by Dr. T. Collin Campbell.
Sorry to be contrary, but T. Colin Campbell’s “The China Study” should put this issue to rest. Please consider the information presented there. The methodology is impressive.
Campbell recommends a vegan diet–no animal based food at all. He claims that population studies demonstrate that vegan populations do not suffer from the high incidence of cardiovascular disease and cancer that we in the West do with our diets heavy on animal protein.
In fact, those are direct quotes from comments that have been left on my blog over the past year. I can’t even show you some of the emails people have sent because the language might offend you.
Usually I direct those folks to Chris Masterjohn’s excellent critique of the China Study. Now, however, I’ll be sending them over to read Denise Minger’s freshly published China Study smackdown.
Here’s the introduction:
When I first started analyzing the original China Study data, I had no intention of writing up an actual critique of Campbell’s much-lauded book. I’m a data junkie. Numbers, along with strawberries and Audrey Hepburn films, make me a very happy girl. I mainly wanted to see for myself how closely Campbell’s claims aligned with the data he drew from—if only to satisfy my own curiosity.
But after spending a solid month and a half reading, graphing, sticky-noting, and passing out at 3 AM from studious exhaustion upon my copy of the raw China Study data, I’ve decided it’s time to voice all my criticisms. And there are many.
Denise got hold of the raw study data and took it apart with a fine-toothed comb. And what she found is that the claims Campbell made in his China Study book are not supported by the data. She also found important data points Campbell never bothered to mention in the book because they didn’t support his vegan agenda.
For example, Campbell conveniently fails to mention the county of Tuoli in China. The folks in Tuoli ate 45% of their diet as fat, 134 grams of animal protein each day (twice as much as the average American), and rarely ate vegetables or other plant foods. Yet, according to the China Study data, they were extremely healthy with low rates of cancer and heart disease; healthier, in fact, than many of the counties that were nearly vegan.
This is just one of many cases of the selective citation and data cherry picking Campbell employs in the China Study. Denise’s critique masterfully reveals the danger of drawing conclusions from epidemiological studies, which can only show correlations between variables – not causal relationships. Campbell should be well aware of this. After all, in his book he rails against the nutritional bias rampant in the scientific community. Yet nowhere is such bias more evident than in Campbell’s own interpretation of the China Study data.
Ultimately, I believe Campbell was influenced by his own expectations about animal protein and disease, leading him to seek out specific correlations in the China Study data (and elsewhere) to confirm his predictions.
Campbell’s response to previous critics of the China Study has been something to the effect of: “I’m a trained scientist. Therefore you should believe me and not my critics.” That is a weak argument – to put it mildly. You don’t need six years of graduate school to learn to think critically. Nor does having a lot of letters after your name make you immune to biased thinking or intellectual blindness. A lot of smart, educated people believed the cholesterol hypothesis for decades. But that never made it true.
You can read more – and I mean a lot more – over at Denise’s blog. I recommend starting with her article China Study: Fact or Fallacy? For many of you, it will be more than enough. But if you’re interested in this stuff, she has written several other articles worth reading.
There are also reviews of Denise’s article at Free the Animal, Whole Health Source, Robb Wolf and PaNu. If you don’t have time to read Denise’s article, read Dr. Harris’s review at PaNu. It’s the next best thing.
Rest in peace, China Study.
P.S. You might also want to check out this debate between T. Colin Campbell and Loren Cordain on human protein requirements. Notice that Cordain’s articles contain 164 citations of research studies. How many references do Campbell’s articles contain? Zero. And Campbell’s typical “I’m more educated than the other guy” won’t fly here. Dr. Cordain has some serious chops.