Cordain wrote:
And I am again going to say "associated with lowered risk" isn't causation - it means people who tend to eat whole grains, in our society, are tending not to eat other things. This is the curse of epidemiological research in nutrition - constantly mistaking correlation for causation (see Gary Taubes multiple NYT pieces on diet and the bad research designs that led to "associated with" being taken for causation). In our fast food culture, if you are eating alot of whole grains, you are probably not getting too much sugar and saturated fat.
You are correct about some of what you wrote above, however:
1) researchers do try to control for the influences of those difference/other factors. Can they perfectly control for other factors? No. But again, they do take into consideration what you are stating, and still come out with, for the most part, results showing that those eating lots of cereal fiber (whole grains) to have lower rates of mortality across the board. Furthermore, in one of the more recent studies on this (possibly the one reference in this thread), those with higher cereal fiber (read: grains and whole grains) intakes had lower rates of mortality amongst virtually all groups (smokers and non-smokers, overweight and non-overweight, women and men, those that exercise and those that didn't, etc) meaning that even in people with less healthy habits, and when comparing people of similar lifestyle habits or characteristics, those with the higher whole grain consumption were less likely to die. This is a pretty convincing correlation, and has been found in many other similar large studies.
2) It's kind of funny when people state: "yeah, but those that eat whole grains are probably more likely to be the type of people that follow healthy lifestyle recommendations, i.e., do other healthy lifestyle things: like not smoke, or exercise a lot, or not eat a lot of fat or red meat, or......" whoops! They are basically admitting that not eating a lot of meat or fat might be, you know, healthy! And let's say it isn't the reduction in meat or fat that is helping these healthy lifestylers, maybe it is less calories total, or a little more exercise. Okay, sure, maybe. But if whole grains (and higher carb intake) were sooooooo bad as many seem to think (and maybe you are not going that far, but some CERTAINLY are, some think grains are the root of all evil), then wouldn't the high carb/whole grain eaters be suffering all sorts of ills no matter what other good things they were doing? Based on the over-the-tops rantings of some against carbs and grains specifically (Gary Taubes), then yes, they should. But they're not, they are living longer, healthier lives then those that don't eat grains. I guess at the very least one should conclude from the research that whole grains are not causing negative consequences in people's diets, and they seem to be part of many healthy societies' diets. Serious people need to stop demonizing them.
3) All people trying to make a point in a debate such as the one we are having will of course try and have it both ways with the "only shows correlation" argument. What I mean is: the anti-grain folks will dismiss a study for methodological concerns, or state that an Epi study "only shows correlation", however, in the next breath, will jump and down and champion a study showing the benefits of meat consumption, without quite mentioning the "only correlation" caveat or looking at the methods of the study with the same critical eye. Right? Both sides do this. You sort of did this with the "casein might cause cancer" reference. Yes, you said it unemphatically, but by even mentioning this lowly regarded concept, it shows your bias. People need to be consistent when being critical/cynical concerning the results of studies. The only well-done or convincing studies are not the only ones that produce results you like, and the only poorly done ones or unconvincing one are not just the ones that produce results you don't like.
4) Gary Taubes is a dumba$$. Seriously. I am not saying he doesn't have anything to add to the conversation, but he has had zero training or education or experience in the fields he is critiquing and considering himself an expert on, and now is 100% invested in, literally, making grains and carbs out to be evil. His livelihood depends on it, and is therefore not objective in the least. I would refrain from mentioning him in any serious discussion on nutrition.