The story of "low fat" diets,and how medical evidence is influenced by politics

Interesting story in NPR about low fat diets, and emerging evidence that they may ultimately be harmful

The story is interesting in of itself, and I agree with the main premise- diets low in fat and high in processed carbohydrates are unhealthy, and healthy fats SHOULD be part of most people's diets.

I am in many ways more interested in a second story here- the way medical evidence is used, and the politics that lead to medical "same think" and prevents implementation of new information.  As was noted in the article, Walter Willett (Chair of Nutrition at Harvard) was concerned that the classic food pyramid (with a focus on high carbohydrates and low fat) was misguided, but had trouble publicizing concerns because of political factors.

Why is this important?  Because one of the assumptions of the ACA (Affordable Care Act, aka Obamacare) is that we already know what we need to know, and what we need to focus on is have physicians cede their judgment and rely more and more on evidence-based guidelines.  This is a mistake.

The great baseball writer Bill James, on his wonderful website Bill James Online in the "Hey Bill" section, had a great recent commentary on the dangers of assuming we already know everything we are going to know:

"I remember my Grade School principal, who attended college just after World War I, told us that when he studied chemistry in college, his professor told the class that they were studying science at the right time, because all the important discoveries had been made now; everything important that was going to be known was known, now, so it was a good time to study science. He told us this, of course, to point out the absurdity of assuming that the search for knowledge is ever finished. . . .. . When Perry Miller was in graduate school at the University of Chicago, late 1920s, he told his advisor that he wanted to study the Puritans. The advisor told him that the Puritans had been studied to death, everything that could be known about them was already known, and he should choose some other subject to work on. He got a different advisor, and stuck with the Puritans. He spent most of his career studying the Puritans, and became one of the greatest historians of the 20th century. He had dozens of protégés over the years, and many of THEM spent THEIR careers studying the Puritans, and many of them went on to distinguished careers, studying the Puritans. . . .. .. Again, the inherent absurdity of suggesting that a field of knowledge is ever "finished". No field of knowledge is ever finished. The intellectual understands that, and accepts it. It's Black Letter Law. A college undergraduate in Physics is allowed to challenge Einstein--if he has argument to make. . . . .. .. It isn't that way, in the rest of the world, and I have spent my career battling this. . ..this turgid, anti-intellectual assumption that everything worth knowing is already known. The non-intellectual world assumes that knowledge is the property of experts, that people who are not experts are not allowed to challenge the experts, but can only learn from them. When I started writing about baseball, I was the undergraduate in Physics who was challenging Einstein; not Einstein, but Casey Stengel, Sparky Anderson, Dick Young and the Elias Charitable Foundation. In the minds of many people I HAD to be wrong, because these other people were the experts, and I hadn't even played the game, so of course I couldn't be right and the experts wrong. I still get the same argument today, in a different form; people will tell me that the advantage inherent in sabermetrics has played itself out now. Everybody knows these things, so the advantage that WAS there, in the Moneyball era, has evaporated. Same argument; everything is known now; shut up and let us go about our business. The gentleman had forgotten this Black Letter Law, and had lapsed into the assertion that I shouldn't offer a novel theory about this, because. . .well, this has been studied; everything worthwhile is known about it. I didn't want to bust his balls about it; I assumed that he would be embarrassed if I pointed out to him what he was saying, so I tried to say it in the gentlest way I could, saying that I would be surprised if any historian were to make that argument. . .. .. .... ...You, on the other hand, I will bust your balls. Pay more attention in class, kid. If you were half as smart as you think you are, I wouldn't have had to explain this to you."