The recent decision to eliminate trans fats by regulatory fiat is an interesting example of intervention breeding intervention. It's safe to say everyone in my generation (I was born in the mid 1980s) was brought up on the Food Guide Pyramid. Unlike the vaunted Swanson Pyramid of Greatness we now know that the advice given in the Food Guide Pyramid isn't great. (Even South Park jumped in on the conversation.) The Pyramid taught that grains were the foundation of sound nutrition and that fats, particularly saturated animal fats, were bad. These fats were thought to cause heart disease and a whole host of issues.
The reality is that the sugar found in grain products like bread and pasta are the heart disease culprit. The Pyramid, designed by well-intentioned folks at the USDA and backed up by the CDC incentivized the use of partially-hydrogenated oils as a substitute to saturated animal fats. These partially-hydrogenated oils are a major source of trans fats. It turns out that the Food Guide Pyramid was wrong and your grandma was right: excessive carbohydrate consumption is bad for you, butter is better than margarine (often containing partially-hydrogenated vegetable oil), and animal products build healthy bodies.
So, it seems to me, if it weren't for the demonization of saturated fats and animal products in general, we wouldn't have been eating so many trans fats from partially-hydrogenated oils over the past 30 years. We'd have been following the same rules our grandmas taught us. There wouldn't be any need to ban trans fats because the crusade against the healthier alternative wouldn't have happened. This is, it seems, a negative outcome of government domination of the health conversation. The fitness community has been on the low-carb-is-best bandwagon for a long time. The rest of us are finally catching up.
I hope in the future school lunches are more in line with the "carbs aren't so great and animal products are" view. I suspect this will not only make them healthier for the growing bodies and minds of our children, but kids will actually want to eat the food.