You should major in whatever subject you enjoy. Your focus in college should be on getting into med school; not what specialty you plan to enter after med school. On avg, non-science major pre-meds have a slightly higher acceptance rate into med school then science (bio) majors. That shouldn't disuade you from majoring in bio if that's what you want to do though, because if you enjoy your major, you are more likely to do well in the classes and maintain a high GPA. I'd reccomend reading a med school admissions advise book before starting college so that you can have some idea of what med schools are looking for too. Good luck!