More than two-thirds of Americans over the age of 65 take vitamin supplements. Here’s the NYT on the downside for a hooked generation: “Often, preliminary studies fuel irrational exuberance about a promising dietary supplement, leading millions of people to buy in to the trend. Many never stop. They continue even though more rigorous studies — which can take many years to complete — almost never find that vitamins prevent disease, and in some cases cause harm.”