And ultimately, the plastic cutting boards are more sanitary, Scott said, because they're cheaper -- so people are more likely to throw them out and replace them. Fact or Myth? The makeup at a cosmetics counter is unsafe to use -- it harbors a multitude of germs.
Answer: Probably a Fact
The safety of using sample cosmetics from the counter may depend on how they're used, but the prospect of what could be in that makeup is enough to keep Scott away from them.
"I don't like that idea at all," she said. "There is the possibility that someone handled the cosmetic who had pathogens on their hands or a skin infection or an eye infection. That all might be transmitted by that cosmetic."
There doesn't appear to much hard data on what the cosmetics at the counter contain, but their usage could lead to the spread of infection.
Scott's advice is to stick to single use samples and avoid the communal beauty sources.
Fact or Myth? A dog's mouth is cleaner than a person's mouth.
If you heard this myth, it probably came from a dog lover as they justified why they let their pet lick their face.
And in one sense, they may be right: A dog's mouth is likely to contain fewer microbes that are harmful to humans.
"If I were forced to be bitten by a dog or a human, I'd take a dog," said Hendley.
But that doesn't mean a dog's mouth has fewer microbes, or that it's "clean."
"I'm thinking, what was the dog last licking?" said Scott.
Hendley and Scott noted that dogs tend to lick themselves, particularly after scraping themselves, and their mouths tend to come in contact with animal feces.
Scott also noted that germs can be picked up by stroking the animals, and you should wash your hands anytime you touch them.
Fact or Myth? Airplanes are a major source of contamination because of the recirculated air.
Airplanes put many different people in a confined space for several hours with the same air. Small wonder that some see planes as flying germ houses.
But while germs may once have recirculated freely, new technology may have removed some of the flight concerns.
ABCNews OnCall+ has previously looked at the issue, and travel can increase risk of flu (which comes from a virus, not a germ), but that is a concern in any crowded area, not just an airplane.
The recirculated air, however, is not as much of a concern as it may once have been.
"It probably was true in the sense that inside of an aircraft cabin, if filled to capacity, you would have a lot of people breathing germs in and out," said Sattar.
But, he said, "More recent aircraft design has created engineering controls which reduce that risk."
Sattar notes that HEPAs, or high efficiency particulate arresters, which were developed around World War II, trap tiny particles in the air so that any particle that might be carrying viruses or bacteria is caught when viruses pass through the air system in the aircraft.
So planes, like any crowded area, pose an increased disease risk, but it isn't clear how much, if any, of that is due to the recirculated air.
Sattar also noted that the World Health Organization will be examining this issue to ensure that passengers aren't sharing illnesses with their fellow travelers.
Cold & Flu season is here! Visit the ABCNews.com OnCall+ Cold & Flu Center to get answers to all your questions about these nasty germs.