Lots of my patients take vitamin supplements. I don’t recommend them. My patients don’t ask me about it, they just tell me. In the absence of a specific vitamin deficiency or medical condition, there is absolutely no evidence that any vitamin improves any health outcome. I’ve always assumed that vitamins are generally ineffective, but harmless. Some patients are very eager to feel like they’re doing everything they can to be healthy, and I usually decide not to say anything and instead save my...