This study says that in older women, those who ate more of current dietary guidelines (fruits, vegetables, whole grains, low-fat animal products) had a 30% less death rate from all causes, but especially cancer and cardiovascular disease.
This article describes two studies looking at the relationship between eating habits and non-Hodgkin's lymphoma (cancer of white blood cells). One showed that people who ate most vegetables had a 42% lower risk of non-Hodgkin's lymphoma; the other showed a 51% lower risk. [I'm not sure exactly what they were looking at here--the study design sounds dubious the way the article describes it--but that's not relevant to my point.]
This article describes a study finding that people who increased consumption of fruits and vegetables by approximately two servings per day reduced their risk of head and neck cancer by 6%.
(Incidentally, the Book of Daniel apparently agrees with these studies, according to Wikipedia. I'll have to pull out my Bible and see if I can find this.)
I think the way they provide this information is interesting, and not very effective. "Vegetables/fruits/whole grains lower your risk of X, Y, and Z." It's a perfectly legitimate and honest way to present their findings. But it has no real impact to me, viscerally or psychologically. Why? I think it's because (a) I don't know what my base risks of X, Y, and Z are, and (b) my assumption is that my risk is pretty low ("it can't happen to me" fallacy). So why do I need to worry about lowering my risk any further? Can't be that important. Result: I don't really care about this information.
But what if the scientists and journalists wrote it this way? "Eating two or more servings of junk food daily increased older women's risk of death by 43%." "Replacing vegetables with junk food increases your risk of non-Hodgkin's lymphoma by 70%." That means more to me. They're telling me that this is something I'm (probably) doing that's endangering my health by a lot.
Admittedly, they'd have to redesign new studies to be able to say these things. But it's interesting that scientists are looking hard at what's healthy--on the assumption that we don't know--and ignoring what's unhealthy. The basic assumption that they, and we, seem to have, is that an unhealthy diet is the standard to judge all things by.
I wonder when this happened, and how it coincided with the growth of nutritional research. And I wonder what it would take to change it.