As if flying isn't already bad enough, here's another reason to avoid the airways:

Jet bloat.

Seems your intestinal gases expand the higher you rise in altitude, which can lead to some uncomfortable bloating, pain and embarrassing moments -- for you and your seat mates.

And many of the strategies we follow to cope with air travel can actually, er, backfire, says Dr. Patricia Raymond, a gastroenterologist who practices in Chesapeake, Va.

Chewing gum or sucking on candy to reduce the pressure in our ears while the plane is ascending can cause us to swallow even more air. Same for drinking caffeinated sodas -- the more fizz, the more volume, she says.

The expansion of gases at high altitudes has been a topic addressed by the aeronautics industry for years.

"Everybody has noticed this," Raymond said about the expansion of air at higher altitudes. "Even though they don't serve an awful lot of food anymore on the planes, the bags of chips are inflated like a little pillow. It wasn't a little pillow on the ground."

The same thing happens in people. Most people carry about 400 milliliters of gas in their intestinal area, about the volume of a small cantaloupe, she said. But people experiencing gassy problems may carry as much as a liter of gas. That volume at sea level can more than double at 30,000 feet.

Fortunately for your neighbors, most of the resulting flatulence is odorless because it's due to excessive air. But passing this type of gas "can be relatively embarrassing because of noises," said Raymond, who is a medical consultant for CharcoCaps Homeopathic AntiGas capsules.