T. Colin Campbell has chosen to not participate in any discussion of his own "scientific results". Take a look at his last word on the topic, note metadiscussion of what "science is about" rather than actually discussing any science, and check the shoes.
The great thing about the Internet, of course, is that it is impossible to censor anything. I'm pasting the comments I submitted to Campbell's site below. These were not approved. Compare with the openness displayed by Denise Minger in publishing comments from all comers, and fostering open discussion. Draw your own conclusions. If you have submitted comments to campbellcoalition.com that were not published, feel free to post them in the comments here. I'll send through anything that isn't overt spam.
To be fair, these comments may yet show up. There is a perfectly acceptable explanation that they haven't been published yet. I'm sure most bloggers have experienced "falling behind in comment moderation". If these comments are published, I partly retract my criticism. But the main portion remains valid: exchange of information is crucial to scientific progress. If you're not willing to exchange information, you're not interested in scientific progress.
I posted this just because it seemed odd to be revising such a benign comment. Who does this, and why?
Uh, why did your answer to my original question change from ““Dr. Campbell said he will be able to post comments now and then, although he cannot respond to every question.” to “Dr. Campbell said he will participate to the extent possible.”? Those seem like they say the same thing to me.
At any rate, I expect Dr. Campbell will find it a better use of his time to respond to specific points here rather than having to write lengthy detailed work such as above.
Here's a harder question:
From the response above:
“First and foremost, our extensive work on the biochemical fundamentals of the casein effect on experimental cancer in laboratory animals (only partly described in our book) was prominent because these findings led to my suggestion of fundamental principles and concepts that apply to the broader effects of nutrition on cancer development.”
Can you explain what these fundamental principles might be, or at least direct me to a detailed discussion? Proteins are broken down in to amino acids in the gut (at least in healthy individuals). These amino acids are then transported throughout the body, where they may be used to build new proteins. How does a specific mixture of amino acids trigger cancer growth? And of course I doubt most free-living organisms eat large quantities of isolated casein. So if I eat a meal containing casein, the mixture of amino acids absorbed reflects that off the total protein content of the meal, not just the casein.
It seems that in order for casein to have a specific role, it would need to trigger some other biological response beyond it’s simple amino acid content. For example, we know that most cancers have a very high glucose requirement, as they largely rely on anaerobic glucose metabolism for energy. We might then expect insulin to be required to stimulate glucose transport. Some cancers do indeed show higher expression of insulin receptors, see e.g.
http://cancerres.aacrjournals.org/content/52/14/3924.abstract
From this we might hypothesize that dietary carbohydrates would drive cancer growth by providing both a supply a glucose and increased insulin secretion. It further can encompass other observations, e.g. the association of dietary fat and cancer. When eaten in combination with carbohydrate, fat will amplify insulin secretion.
Returning to your hypothesis that casein has a unique potential to stimulate cancer growth. What metabolic pathways are followed that create the “casein effect”? Is there some specific hormonal signal uniquely stimulated by casein?
And a link to a multivariate analysis that would answer at least some of Dr. Campbell's objections:
Here is an interesting blog on a multivariate analysis of China Study data:
http://healthcorrelator.blogspot.com/2010/07/china-study-again-multivariate-analysis.html
I put these comments under the post "The Challenge of Telling the Truth:
Nelson,
Your suggestion about keeping an “open attitude” is a good one. However, you need to keep an open attitude about scientific evidence as well. The way you talk about “truth of health” sounds a lot more like religion than science. Perhaps this is simply a communication gap. I sincerely hope that you and your father have the sort of open and inquisitive minds required for scientific progress. There is no absolute “truth” in science, as this would imply we have perfect information. I doubt even the staunchest supporter of any dietary dogma would claim that we have perfect understanding of the deep complexities of human biology.
I will reiterate here what I have said elsewhere: scientific progress is about two-way communication. You and your father likely have information that supports your hypotheses, information that others do not have. However, I’m sure you’d agree that others have information that you do not as well. The only way to reach “agreement” is communication, so we’re all on the same page. This is why dialog is so fundamental to scientific progress. I hope you and your father will participate in this dialog.
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“Despite lacking an adequate understanding of statistics and causality, this person used her intelligence and writing skills to compose a critique that might seem persuasive to laypeople.”
You might wish to expand on this a bit. It sounds like you’re saying she is both stupid (“lacking…understanding”) and intelligent in the same sentence. And I’m sure you would agree that “laypeople” need to have greater understanding of the issues so that they can make informed decisions, rather than simply picking an “expert” to blindly follow. Perhaps you can provide a little Statistics 101 discussion for us to better illustrate the shortcomings in Ms. Minger’s analysis for the lay public?