We've all been there: seated next to a snotting, sneezing, coughing person with no escape route available, worried that the next day we'll be the one hacking. But the truth is, catching an illness can't always be blamed on the obvious offenders.
Though you can pick up germs just about anywhere (disturbingly, viruses can linger on surfaces such as ATMs and checkout-aisle pens for 48 hours), actually coming down with a cold or flu is a complex process -- one that you can outsmart by following these stay-healthy tips.
Wash, Rinse, Repeat
"The number one thing you can do to protect yourself from a cold or flu is to wash your hands thoroughly and frequently," says microbiologist Andrew Pekosz, Ph.D., of Johns Hopkins University.
Lather up with running water and soap (antibacterial soaps are no better than the regular stuff) and scrub your palms, between your fingers, and the backs of your hands for a minimum of 20 seconds. In a pinch, you can use hand sanitizer that's at least 60 percent alcohol, according to the Centers for Disease Control and Prevention.
Moisturize Your Air
Turns out, very humid air might be toxic to flu viruses. Scientists aren't quite sure why, but one possibility is that droplets that contain the virus shrink quickly in arid environments, allowing them to float around longer; in moist air those same droplets might remain heavy and fall to the floor faster, says Ted Myatt, Sc.D., an environmental scientist in Boston. Invest in a humidifier that keeps the humidity level between 40 and 60 percent.
Skip That Second (and Third) Drink
Alcohol can impair your white blood cells' ability to combat viruses for up to 24 hours after you overindulge, according to a study in BMC Immunology. Keep your imbibing to a reasonable one drink per day during cold and flu season, says Pekosz.
Don't Rely on C
Yes, you read that right: Though it's been touted as a cold fighter for decades, vitamin C has never been proven to fend off a cold or flu. And multiple studies show it does zilch to speed up recovery if you're already sick.
People who routinely get fewer than seven hours of shut-eye a night triple their risk of developing a cold compared with those who doze for eight or more hours, according to the Archives of Internal Medicine. When sleep-deprived, your body may produce too many cytokines, the proteins that trigger cold symptoms when you're sick.
Taste the Rainbow
Immune-boosting antioxidants in brightly colored fruits and veggies battle the free radicals that dampen your natural defenses, says Josh Miller, D.O., an internist at the Cleveland Clinic. Eat plenty of fare such as red beans and berries (the brighter the hue, the higher the antioxidant count) and drink green tea.
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Most viral infections seep in through your nose and eyes, not your mouth. In fact, in a Journal of Infectious Diseases study, only 8 percent of people fell sick after smooching someone who had a cold. "It's actually safer to kiss someone who's sick than shake his hand," says microbiologist Charles Gerba, Ph.D.
Staying in a Hotel Room: True
A third of hotel room surfaces were still coated in germs nearly a full day after a sick person spent the night, says research from the University of Virginia School of Medicine. Protect yourself by swabbing hard surfaces like doorknobs, light switches, and remote controls with hand sanitizer or alcohol-based wipes.
Using an Old Toothbrush: False
No need to toss your toothbrush after recovering from a cold or flu--you can't reinfect yourself. When you fall ill, your immune system creates antibodies specific to the strain of virus you have. Those good guys stick around to make sure you never get the same exact virus again, says Josh Miller, D.O.
The Sneaky Life of a Virus
Day 1: Someone coughs, spewing viruses all over the grocery-cart handle. You grab the cart and pick up germs along with your dinner.
You rub your nose or eyes, transferring the virus into your sinus system.
Now in your airways, cold or flu viruses begin to reproduce like crazy and block your body's immediate immune response.
Day 2: You feel fine, though virus cells are making their way to your lungs. Also, you're now contagious.
Day 4: You feel hellish.
Many of your symptoms--sneezing, coughing--are side effects of the viral attack on your immune system.
While you can treat those symptoms with meds, drugs won't eradicate a cold or flu. Only time, lots of fluids, and rest will.
Day 5: If you picked up a cold virus, the worst is almost over. You're likely no longer contagious, even if you're still sniffling. If it's the flu, though, you feel as if you've been hit by a truck. You might suffer through a fever, nausea, vomiting, or diarrhea for the next few days as your immune system works like crazy.
Day 10: You could still be contagious for up to a week after your first flu symptoms. Cough or sneeze into a tissue or the crook of your arm -- you won't spread germs via your inner elbow. Better yet, stay home until you're good as new.
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