Regarding the Advisory Committee, "According to federal regulations, the panel that writes the dietary guidelines must include nutrition experts who are leaders in pediatrics, obesity, cardiovascular disease, and public health. Selecting the panelists is no easy task, and is subject to intense lobbying from organizations such as the National Dairy Council, United Fresh Fruit and Vegetable Association, Soft Drink Association, American Meat Institute, National Cattlemen's Beef Association, and Wheat Foods Council. (Abboud L. Expect a food fight as U.S. sets to revise diet guidelines. Wall Street Journal: August 8, 2003, B1.)" In a way, it parallels discussions about the FDA: it's a panel of scientists and experts, yes, but it's still heavily influenced by politics/money. Here's an article showing a disconnect between current science the guidelines BEFORE 2005. Consider also the policy for trans fats in America. This is a molecule that has no redemptive features whatsoever, yet we allow less than .5gs in a serving to be classified as "trans fat free." I can't point to resources that show you that these expert panels are corrupt, but their policies necessarily reflect some compromising with people whose interests should not be at issue here.

Ultimately, here's how I see it (which may not be accurate at all): we start at a traditional diet relatively high in fat, the government tells us "woah fat is bad" because some research inconclusively shows as much, we do what the government says and replace the fat in our diet with carbs, and our health deteriorates. I'm not saying we should go unguided. Just the opposite, in fact. We had guidance for thousands of years regarding what we should eat. It's called culture. I think that form of guidance was doing a very good job and that we have done worse attempting to change it. Anecdotally, consider that the societies where people have changed the least from their traditional diet have the best health, regardless of the specific macro-nutrient profile of that diet: the Japanese eat relatively high carb, low protein, the French eat relatively high fat, etc. Of course, other factors at work such as lifestyle and so on play a role, so I don't rest my argument on that point (though the studies tracking people living modern lifestyles while dieting traditional do support that proposition).

So again, I would say that I don't think having some guidance is bad--I just don't think that guidance should be dressed up and treated as the gospel, especially when the process by which it is created is subject to incentives that lie outside the public health. There are other sources to look to besides the government when it comes to what to eat. Indeed, if you look at the dietary guidelines for other countries, only our's attempts to be SO comprehensive. The guidelines as they are are used to justify serving students pizza for both breakfast and lunch. The worst mother would tell you this is terrible for your health. Is that quality of guidance really better than nothing?