In your opinion, how much and what is a spouse's obligation to confront about unhealthy and unsafe habits?
My wife of five years is great. However, certain things have me concerned. She doesn't like to exercise. She has a gym membeship, but hasn't set foot in the gym in over two years. She could happily avoid fruits and vegetables, except for grains. She drinks quarts of Diet Coke every day. She also is significantly overweight, which doesn't affect my desire for her, but could affect her health. She also will stay late at her school in an unsafe neighborhood.
It is not my style to be a nag. Also, while everything I describe raises the odds of trouble in the future, it's still not guaranteed to happen. Moreover, I could conceivably ruin her fun only for her to die relatively young from an airplane crash. (G-d forbid) So, I want to hear from others. How much do you think a spouse should intervene?