Following New York City’s lead, California’s hotshot governor, Arnold Schwarzenegger has just signed a ban on trans fats into law. It takes effect in 2010. This, plus labeling requirements for packaged foods, ought to end the practice of partially hydrogenating vegetable oils. My prediction: trans fats are soon to be a thing of the past. This should have happened a long time ago, as there are plenty of substitutes. So the big question is whether the disapperance of trans fats will have any effect on health. I hope it helps reduce the risk of heart disease but nobody should expect it to help people maintain weight. Whatever substitutes get used will have the same number of calories. Why are New York City and California doing this? Because it might do some good and is politically expedient. Getting vending machines out of schools, stopping marketing to children, and getting everyone on bicycles is a lot harder.