If you're a Type B, you roll with the punches. You're relaxed, take life a day a time, and handle stress without cracking. That translates to a higher quality of life and lower likelihood of heart disease—less anxiety strengthens the immune system. The more we chill, the better off we are, says Miller: "You don't want to get locked into a stressful, tense state of mind." Over the long term, he adds, relaxing and managing stress effectively will lengthen your life, help your heart and gastrointestinal system, and just make you feel better overall.