Going in and out of air-conditioned buildings is harmful
Big temperature swings don't make you vulnerable to colds, says Michael Seidman, M.D., director of otologic and neurotologic surgery for the Henry Ford Health System, in Michigan.
Real threat: The building's air won't harm you, but its surfaces might. Some viruses can survive on surfaces like doorknobs for days. Wash your hands regularly, and go as you please. (Try these eight ways to fight household germs.)
If water is stuck in your ear, stand on one foot and tilt your head
"Your ear canal is curved, so just tilting your head often isn't enough to release the water," says Dr. Seidman.
Better move: Tilt your head so the waterlogged ear faces down. Place the tip of your index finger in the cuplike spot at the bottom of your ear, and position your thumb behind the ear on the cartilage above your earlobe. Hold firmly and wiggle your ear to straighten the ear canal and dislodge the water.
Campfire or grill smoke is dangerous
The smoke's particulates can damage your lungs, says A. James Mamary, M.D., of the Temple lung center.
Protect yourself: Stay upwind and you'll be fine.
Don't drink from a hose — it's germy
Verdict: Partly true
"No germs live specifically in garden hoses," says Charles Gerba, Ph.D., a professor of environmental science at the University of Arizona. However, the hose's end may have rested in animal poop.
Stay safe: Keep your lips off the hose. Or go inside the house, for cripes' sake! (Learn how to beat six everyday infection spreaders.)
Dunk an open wound into the sea because saltwater helps heal
The sea is full of bacteria, which can enter your cut and cause sores and fever.
Clean fast: Spit on it. "A digestive enzyme in saliva can clean wounds and kill microorganisms," says dermatology professor Adnan Nasir, M.D., of the University of North Carolina at Chapel Hill. Then apply a waterproof or liquid bandage, like New-Skin, to block bacteria.
Scratching a bug bite makes it worse
Light scratching inflames immune-system messenger proteins at the site, intensifying the itch, says Dr. Nasir.
Cool it down: Hold a chilled beer or an ice cube on the bite. (Discover 31 more things to do with beer — besides drink it.) "Low temperatures slow the body's chemical reactions and make the skin's itch signals travel sluggishly to the brain," says Dr. Nasir. For nagging bites, use Campho-Phenique antiseptic solution, which calms itches with camphor.
Don't swim within 30 minutes of eating
More blood is drawn to your GI tract after eating, which can cause minor cramps, says Christine Carter-Kent, M.D., a gastroenterologist with the Cleveland Clinic.
Feel better: If you swim and feel ill, sit and wait it out.