Does double-dipping spread germs? And what's the deal with the five-second rule?

It's hard not to be a germophobe. After all, we live in a germ-infested world. However, misinformation tends to spread faster than nasopharyngitis (a.k.a. the common cold), so we rounded up some of the most prevalent strains of viral wisdom to sort out the old wive's tales from the actual facts.

The 5-Second Rule
Verdict: Half-truth

Off-the-floor eating is far from ideal, but if you act fast, it isn't that gross, statistically speaking. In a new study from Aston University, researchers dropped foods on floors and let them sit for anywhere from three to 30 seconds. Then they tested the levels of E. coli and staphylococcus aureus and found that food picked up just a few seconds after being dropped is less likely to contain bacteria than if it's left for longer stretches of time—no surprises there. However, both the type of food and the type of floor make a difference: drier foods dropped on carpets were the cleanest ones in the study, while sticky foods left on smooth surfaces for more than five seconds were the most germ-infected.

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You Can Catch STDs From a Toilet Seat
Verdict: Myth

Unless you're having sex on said toilet seat, there's no need to worry about catching a disease on one. Bacterial and viral STDs begin to die the second they leave your body, and upon hitting a cold, hard toilet seat, they promptly kick the bucket. The only STDs that could theoretically be passed from toilet seat to body are parasitic ones (think: lice and crabs). One parasitic STD called trichomoniasis is known to pass from damp objects to people, according to the Office on Women's Health. However, parasites also don't live very long when away from a human host and can't really grab on to or move along smooth surfaces like toilet seats.

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Hand Dryers Are More Sanitary Than Paper Towels
Verdict: Myth

Any points hand dryers get for eco-friendliness, they lose for germiness. A recent review of 12 studies found that paper towels are far more hygienic than hand dryers, which actually blow bacteria all over your hands, as well as the entire bathroom. Plus, it turns out that the friction created by actively wiping down your hands with towels actually helps scrub off unwanted bacteria.

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Toilet Water Can Splatter Onto Your Toothbrush
Verdict: Fact

Listen to your girlfriend and put down the toilet lid. A 2012 study published in the Journal of Hospital Infection found that a single flush can spray the diarrhea-inducing bacteria clostridium difficile nearly 10 inches high. Even if you keep your toothbrush kept out of the spray zone, you could still be brushing with fecal matter. On a particularly gag-inducing episode of MythBusters, hosts Jamie Hyneman and Adam Savage found that even toothbrushes that never entered a bathroom were speckled with poop particles. That shit's everywhere.

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Double-Dipping Spreads Germs
Verdict: Fact

That's strike number 265 for George Costanza. Double-dipping really does transfer oral bacteria to your dip, according to research in the Journal of Food Safety. Still, even if you single dip—and so does everyone else at your party—dips naturally produce their own bacteria as they sit out. At your next cocktail party, just stick to plain crudités.

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