Misconceptions about Germs and Hygiene - mental_floss on YouTube (Ep. 12)

Hey, I'm Elliot, and this is Mental Floss on YouTube

Today, I'm going to talk about some misconceptions about cleanliness and germs

Misconception number one, the five-second rule. If you've been to elementary school, and I hope you have

I'm sure you've heard this one. Some claim that if you pick up food off the ground within five seconds of it being dropped

it's germ-free and safe to eat. There have actually been scientific studies on this

and they found that bacteria does make its way onto food immediately after it hits the ground

It is a smaller amount, though, so the sooner you pick it up, the less bacteria it will have

And the surface that it's dropped on does make a difference. There's less bacteria transfer from a carpet than there is from a smooth surface

But the germs aren't like 5, 4, 3, 2, 1, because they can't. They don't have that kind of self-control

Misconception number two, soap kills germs. Soap is actually a surfactant. So, when you wash your hands, you combine soap with water, then surface tension decreases

This allows for the bacteria to be released from your hands. Then they just go down the drain

They go, like that. Misconception number three, viruses stay alive on hard surfaces for a long time

It's normal to be a little weirded out about touching things like doorknobs and railings in public spaces

but the truth is viruses and bacteria do die on hard surfaces. How long they stay alive depends on the specific type The flu virus typically only survives between two and eight hours and the cold virus lasts longer but it unlikely to get you sick after 24 hours and the herpes virus dies after four hours

Misconception number four, urine disinfects, burns, and stings. Urine is not a disinfectant

See, aren't you glad you watched this episode? In fact, a 2014 study conducted by the Loyola University Health System

found that there's actually bacteria in healthy human bladders. So, not only is your urine not a disinfectant

it's also not that safe slash sterile in general. Speaking of toilet stuff, misconception number five

the toilet seat is very germy. Well, it's probably not like the cleanest place on earth

but you're unlikely to get a disease from it. And it's definitely a misconception that you can contract an STD from the toilet seat

According to a 2002 University of Arizona study, there's around 49 germs per square inch on the toilet seat

Compare that with the around 21,000 germs per square inch they found on people's desks at work

Still, you shouldn't touch the toilet seat with your hand. Plus, the flush handle and other surfaces in the bathroom are even dirtier

so make sure you wash your hands. Why don't you just wear gloves all the time? Misconception number six, everyone washes their hands

According to a 2013 study from Michigan State University, 10% of people do not wash their hands after using a public restroom

Gross! And that's here in a developed country where we have all the right resources. Handwashing can reduce the risk of diarrheal diseases

which affects 1 billion people around the world each year A 2003 review of seven handwashing studies found that if everyone did wash their hands there would be between 0 million and 1 million fewer deaths from diarrheal diseases annually That insane Misconception number seven everyone washes their

hands correctly. According to the same Michigan State University study that I mentioned earlier

95% of people are not washing their hands long enough to get rid of germs. So let's take this

into the bathroom so I can show you how to wash your hands. Okay, so the first thing you're going

needed some clean water. It can either be hot or cold. I prefer tepid. You just lather your hands

like this. Now, once you have your hands nice and lathered, you want to do this for about 20 seconds

The Center for Disease Control and Prevention says that that length is about the same as singing

Happy Birthday twice, which obviously I'm not going to do because it's copyrighted actually by

a guy named Tim Birthday. A lot of people don't know that. And also I'm a horrible singer. Then

after you're done, you just rinse it like this. Huh? They didn't know that. Turn off the water

that's important too, and then you dry off your hands. Thank you so much, sir. Misconception number eight

hand dryers just blow germs around. The microbiology department at the University of Ottawa

has conducted studies about this and determined it to be not true. Hand dryers are not blowing germs all over you

Some claim that dust starts to build inside, leading to bacteria buildup, but that has also been debunked

Other studies show that hand dryers blow bacteria around the room, but these have continually been shown to not be harmful

and no outbreak has ever been associated with hand dryers Unless you washing your hands like in the emergency room of your local hospital dryers are fine Also though the cool ones are the ones that you put your hands in and it like the blade You seen those Oh they so cool Misconception number nine

dirty people get lice. Unfortunately, you can wash your hair every single day, but that will

not make lice any less attracted to you. All it takes is head-to-head contact with someone who has

lice. And this happens to 6 to 12 million kids between the ages of 3 and 12 years old in the U.S

each year. They can start wearing a hairnet around and maybe stop hanging around playground

which I should probably stop doing anyway. Misconception at number 10, hand sanitizers cause bacterial resistance

Many believe that hand sanitizers create antibiotic-resistant bacteria, also known as superbugs

Superbugs are real and infect around 2 million people a year, but probably not due to hand sanitizer use

The alcohol in hand sanitizer kills the majority of bacteria on your hands

which involves breaking down the protein in the bacteria's contents. That protein breakdown makes resistance unlikely

It's antibiotics that tend to create superbugs. As long as your sanitizer is at least 60% alcohol

and does not contain either triclosan or triclocarbon, then you're in the clear

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If you have a topic for an upcoming Misconceptions episode that you would like to see, leave it in the comments

and we'll check them out. I will see you next week