Why do some people get sick every winter and others don't? Every winter, I see countless people in my office for flu and cold symptoms. After 26 years in practice, I've found it's pretty easy to predict who’s going to get sick and who isn't. It's not a mystery. There’s a saying that "success leaves clues." Well, so does illness—it’s predictable. What do I mean? Let me explain. Ever wonder why there’s even a "flu season"? Why only during winter? Do viruses and bacteria suddenl