Here's the deal: Yes, your metabolism affects your size, and the faster your personal motor runs, the more calories you'll burn. But the truth is, a slow metabolism isn't the real reason you're packing on pounds. You are the reason.
As a general rule, arrive at the airport no later than two hours before your domestic flight is scheduled to depart. This is somewhat later than the typical suggestion of three hours for an international flight.
A good rule of thumb is to be at the airport two hours early for any domestic flight. The airport you are flying from and the time of day you will be flying are also factors to consider when planning your arrival time. For busy airports like those in Los Angeles, Boston, New York and Atlanta, you should arrive three hours prior to your flight.