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.
Passengers should plan to arrive at the airport at least 90 minutes prior to scheduled departure to allow themselves adequate time for check-in, security screening, and food/beverage or merchandise purchases and be at the gate approximately 30 minutes before scheduled flight departure.