If you’re gearing up for holiday travel, reconsider that red-eye flight. It could mean the difference between a relaxing getaway and a holiday spent sick in bed.

A new study published in Science suggests that there’s a biological reason why changes in our regular sleep cycle, such as working graveyard shifts or experiencing jet lag, make us feel sick.

When our circadian clock receives light signals at the wrong times, the body’s immune response goes haywire, impeding the production of immunity-boosting T cells and leaving us vulnerable to infections.

Disrupting the circadian rhythm is one way holiday travel could hamper your immune system, but plenty of other health hazards are lurking on airplane tray tables, next to coughing passengers, and in seemingly spotless hotel rooms.

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Be Prepared

You can’t always fully prepare for the worst, but if you have a condition that could be exacerbated by travel, take extra precautions and talk to your doctor well in advance of hitting the road.

“Being out of condition prior to a trip and then overexerting can cause aches and pains or worse,” says Susan Theuns, administrative director of physician practices at MedStar Union Memorial Hospital in Baltimore. “If you have a chronic health condition, you may want to have a check-up before leaving to make sure you are fit for travel and the added physical demands of travel.”

Theuns also suggests consulting with a travel medicine expert or the Centers for Disease Control for a list of recommended vaccines and prophylactic medications for travel to specific countries.

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Pack Smart

Luggage space and TSA guidelines might keep you from packing an entire first aid kit, but having a few carry on-sized items on hand will keep you comfortable before you make it to a pharmacy. Dr. Timothy Morley, the Medical Director of Womens Healthy Hormones, recommends the following:

  • water
  • hand sanitizer
  • bandages, gauze, cotton balls, and surgical tape for blisters and abrasions
  • antibiotic ointment
  • medications for:
    • inflammation
    • diarrhea
    • congestion
    • cough suppression
    • allergies

Stay Healthy in the Air

If you’re traveling by plane, drink plenty of water to protect yourself from the low humidity that can cause dehydration and, as Morley warns, worsen chronic diseases like asthma. Morley encourages travelers to drink eight ounces of water for every hour of travel and to limit their consumption of alcohol, coffee, and tea while in the air 

Also be mindful of your surroundings, which have probably come in contact with hundreds of other people that day. “Turnaround time on planes and trains may be quick, so do not assume that anyone has wiped down the trays and armrests,” Theuns says. The same goes for seat pockets, pillows, and blankets.

Bring a bottle of hand sanitizer or a pack of baby wipes to keep your hands germ free.

Don’t Touch 

Airplanes and trains are far from the only sources of germs. Morley says to be mindful of the following soiled surfaces:

  • elevator buttons
  • door handles
  • water fountains
  • phones in hotel rooms
  • ATM buttons
  • condiment containers, including ketchup bottles and salt and pepper shakers
  • TV remotes
  • computer keyboards
  • money
  • bathroom faucets
  • light switches

And don’t slack on your well-being when you return home. Continue to rest, hydrate, and wash your hands often. You can also consult your physician about taking melatonin or other medication to relieve jet lag and help you sleep.

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