This summer I’ll be taking a long trip, but I always get sick after an extended flight. Do you have any suggestions on how I can stay healthy on an airplane?

There are many things you can do to keep yourself healthy while flying. First, prepare your body for a long trip by being in good shape before you embark. Second, take steps to protect yourself from microbes and viruses on an airplane.

Before leaving on your trip, drink more water than usual so that you’re well-hydrated even before you board the plane. If the mucous membranes of your mouth, sinuses, eyes, and throat are well-hydrated they will act as a more effective barrier to microbes and viruses than if they are dry. Keep in mind that the air in the plane is probably much drier than what you’re used to; in Hawaii it’s usually quite humid (52 to 81 percent, depending on the month), but airplane humidity is generally below 25 percent.
To keep your mucous membranes hydrated, I also recommend the following:

-Drink at least eight ounces of water or fluid for every hour that you are flying, and avoid ingesting drinks that tend to dehydrate, like coffee, caffeinated tea, and alcohol.

-Wear a mask over your mouth and nose if you are flying a long distance. This not only helps protect you from airborne microbes and viruses, but may also allow the air you breathe to retain slightly more moisture.

-Use eye drops that moisten your eyes, such as Similasan Homeopathic Eye Drops for dry, red eyes. Apply one drop in each eye for every hour that you are on the plane.

-Use Xlear Nasal Wash, a convenient nasal spray, before boarding the plane, and every two hours while in flight. It contains xylitol, a naturally-occurring compound known to have antibacterial properties. (You can find it at www.xlear.com.)

-Use sugar-free throat lozenges to help keep your throat moist, or use a throat spray every hour while flying. One of my favorites is Source Naturals Wellness Throat Spray, which is available at most health food stores.

I also recommend that you use a waterless hand sanitizer gel that kills germs. Apply it frequently while on the airplane, especially after using the restrooms. And avoid ingesting a lot of sugar; it is known that sugar reduces the effectiveness of your immune system.

Have a great trip!