There are a few myths out there that we’ve all come across at some point, and if you hear something enough, it’s only natural to believe that it’s true. But what these commonly known “facts” all have in common is that they’re not true. Most of them were made up on the basis of misconceptions, misunderstandings, and downright intentional hoaxes.

Check out these 23 “facts” below to see what’s really going on here.

1. You lose most of your body heat through your head.

This is true — but only in infants. After infancy, you lose just as much heat from your arms as you do from your head. The only differences is that, unless you’re wearing a hat, your head is often exposed to the elements.

2. Cell phones give you cancer.

Cell phones use radiofrequency, not radiation. Ionizing radiation has been shown to cause DNA damage and cancer, but radiofrequency has not been shown to do that. Gab away, friends.

3. Different places on your tongue taste different things.

You can sense all tastes on all parts of your tongue.

4. Fortune cookies are a Chinese tradition.

They’re a Chinese food tradition now, but the custom of putting paper messages inside of cookies is actually a Japanese-American invention. It was later appropriated by Chinese-American restauranteurs.

5. Shaving makes your hair grow in thicker and darker.

When hair grows, it forms a tapered end. When you shave it, you cut it off at the thickest, darkest part, so the remaining stubble does look thicker and darker. But it’s not. The growth rate is unaffected, and if you let it grow, it will be the same color and texture as before.

6. Sugar makes you hyper.

Actually, it doesn’t. Studies show that when parents were told that their children had been given sugar, they believed that the kids were more hyper — even when they were only given placebos. The correlation might come from the fact that sugary treats are often eaten at parties, where kids are more excited to begin with.

7. MSG gives you headaches.

Technically, the jury’s still out on this, but there’s no scientific data to support it. All evidence is anecdotal at this point.

8. Glass is a liquid.

Glass is actually an amorphous solid, not a supercooled liquid. Old windows that are thicker at the bottom? They were just poorly made.

9. Sushi means “raw fish.”

It actually translates to “sour tasting,” and refers to the rice, not the fish.

10. Undercover police officers are required to identify themselves.

This myth was actually created by Hollywood. Undercover cops don’t have to tell you who they are, so don’t do anything shady.

11. The monster is named Frankenstein.

The name “Frankenstein” refers to the doctor who created the monster in Mary Shelley’s famous horror novel. His name is Victor Frankenstein. The creature he creates out of body parts never has a name.

12. Wet hair makes you sick.

Wrong again. External temperatures have no effect on your body’s resistance to germs. Although having wet hair in the cold is certainly uncomfortable, it won’t necessarily make you sick.

13. Cold weather makes you sick.

Viruses travel more easily through cold air, which holds less moisture. That’s why people are more likely to fall ill in the winter. But you’re more likely to catch a cold while cooped up inside with germy people than you are outside in the snow.

14. Alcohol keeps you warm.

It makes you feel warm because it dilates your blood vessels, giving your face a warm, flushed feeling. But it also drops your core temperature, actually making you colder. If you feel warm, it’s because your surroundings feel warmer compared to your cooling body.

15. The moon has a dark side.

The same side of the moon always faces the Earth, which is why its surface looks the same each night. The “dark” side is the same color, but it’s just in shadow. “Dark” refers to the fact that the sun doesn’t shine on it.

16. Caffeine dehydrates you.

Caffeine does have a slight diuretic effect (as in, it makes you pee), but a cup of coffee won’t dry you out. That’s because it’s mostly water — which is also why it makes you have to pee.

17. Different sides of your brain do different things.

You’ve probably heard the whole “left-brain, right-brain” thing, but the brain is not so clean and organized. There’s no real distinction, but it seems that skills come from various places. Any part of the brain can contribute to any activity.

18. Dogs sweat through their tongues.

This is more of a misunderstanding. Dogs do regulate their temperature by panting, but it’s not sweat. Dogs actually sweat from their paw pads.

19. The iron maiden was a medieval torture device.

As much as we all love it, this thing never existed in the Middle Ages. It was actually invented as a showpiece in the 18th century to shock circus audiences. Think of them as the bogus Internet rumors of the 1700s.

20. Puritans wore black with big collars and buckled hats.

They actually dressed just like anyone else in late Elizabethan times, with a full range of colors depending on the current fashion. The somber black wardrobe was invented later.

21. Salt makes water boil faster.

People swear by this, but it’s actually a scientific impossibility. Salt raises the boiling point of water, which means that adding salt actually makes water take longer to boil.

22. You have to wait 24 hours to report a missing person.

If someone you know is missing, don’t wait a full day! This dangerous rumor is very false. You can report someone missing at any point.

23. Vaccines cause autism.

No, no, no they don’t. This myth became an issue due to some faulty, manipulated research. The doctor who fabricated the study even had his medical license revoked. Please vaccinate your kids. Because you know what’s way worse than autism? Polio.

(via List25)

Now that you’re more educated, it’s time to spread the truth and get rid of these misconceptions!