Flying is still a scary experience for many. Planes are frightening machines that can be very intimidating. They usually take you to your vacation destination and nothing gets you to where you need to be faster, but all of this comes at a price.
Jet lag is just one issue fliers often face; motion sickness and blood pools in your feet are also common. They come with symptoms that are worse than fatigue and irritability.
Crossing multiple time zones, the quick changes in air pressure, the lack of humidity and oxygen, and the cramped conditions together create a hellish experience for which the body may punish you with swollen ankles, hearing loss, bloating, cosmic radiation, and constipation.
These are just a few of the unpleasant symptoms you can expect that are created by the unfriendly environment of an aircraft hovering at a high altitude.