Have you flown the friendly skies recently? For many people, flying is a headache... quite literally.

An Israeli study of 906 people found that 6% report getting headaches when they travel by airplane. Based on that statistic and a few flight numbers/occupancy assumptions, researchers estimate that this translates into more than 100 million flight-induced headaches per year.

There are several things that could trigger a headache during air travel -- stress, pressure changes, poor air quality, and engine noise. (Not to mention noisy passengers!) To help manage air travel-related headaches, be sure to drink plenty of water (as dehydration can contribute to headaches), get up and walk around during long flights, bring books or music or anything else that will help you reduce stress, pack ear plugs if noise bothers you, and bring some over-the-counter pain relievers.