I’ve been meaning to post my take on the debate about dietary protein (large pdf) between Loren Cordain and T. Colin Campbell. A reader does it for me. A spot on analysis.
I just read the Cordain/Campbell “Protein Debate. I recommend it for Cordain’s concise writeup on the evolutionary/archaeological evidence in favor of a high-protein diet. Read Campbell’s stuff for a chuckle, and a good illustration of why nutrition science and the accompanying public policy is such a screwup. A few highlights:
Cordain’s paper contains no less than 134 references, and his rebuttal to Campbell contains another 30. Campbell, in support of a low protein, low fat, diet provides, uh, let me count, ZERO citations. He manages a few in his rebuttal to Cordain, but a couple of those are to himself, and only one that I saw appeared to be a peer-reviewed article. He makes some fairly bold statements, like “overwhelming findings on the adverse health effects of dietary protein” and “remarkable healing effects now being routinely accomplished by my clinician colleagues”, again with no citations to supporting peer-reviewed literature.
Campbell’s stance appears to be largely one of “because I said so”. The first sentence in his rebuttal is “My critique of Professor Loren Cordain’s proposition almost entirely depends on my philosophy of nutrition”; as opposed, say, to evidence gathered via the scientific method? In fact, he goes so far as to argue in favor of what is essentially sloppy research in nutrition science. The point Campbell is trying (badly) to make is that making precise measurements of the components of a complex system may do little to increase your understanding of it’s overall behavior (look no further than cholesterol research for a good example of “missing the forest for the trees”). But the fact that complex systems often exhibit the “gestalt” of emergent behaviors does not mean we throw the scientific method out the window in favor of “holistic” hand-waving and arguing about whose bullsh*t “philosophy” is superior.
BTW, Campbell isn’t just some wacko off the street. He’s the “Jacob Gould Schurman Professor Emeritus of Nutritional Biochemistry” at Cornell University. So he’s clearly convinced more than a few people that his “philosophy” constitutes sound science.
Cordain, while largely very thorough, fails to follow his own advice that “the data must speak for itself” to avoid “prejudice introduced by charismatic personalities, faulty human judgment and preconceived biases” when it comes to the issue of saturated fat and cholesterol. In particular, he cites the “atherogenic effect of saturated fat”, while providing no references to studies demonstrating said effect. I find this surprising, and illustrative of the dogmatic strength of the lipid hypothesis, even in the mind of an otherwise strongly rational and methodical scientist.