Myth:

The way cabin air is circulated makes the plane a prime breeding ground for colds and flu viruses.

True: A qualified yes because there's no scientific proof that breathing someone else's air in the cabin will make you ill. It's true that some airlines save money by recirculating air instead of purging and replacing it, so Greenberg's advice: Hydrate yourself while on the plane, wash your hands often, and turn off the air vent over your head to not only avoid a stiff neck but also keep your own air around you longer and put off breathing someone else's.