13 Myths That Won’t Die—Even Though They’re Totally False

Think that gum you swallowed in 2018 is still rattling around your insides? Good news: it’s not. Despite what you may have heard, gum does not take seven years to digest. In fact, like other indigestible things (think corn kernels or seeds), it simply passes through your system in a matter of hours.

That age-old myth is just one of many floating around in the public consciousness—some persistent, some downright ridiculous. A Reddit thread asked users to name the dumbest myths people still believe, and the responses are both enlightening and entertaining. Here are some of the most widely believed—and wildly inaccurate—claims that came up:

1. Lie Detectors Are Foolproof
   Polygraphs measure stress, not lies. Your anxiety alone could trip it—and that’s one reason they’re not admissible in court.
2. Wills Are Read Aloud Like in the Movies
   There’s no dramatic family gathering in a mahogany-paneled office. Estate lawyers say people usually just receive a copy in the mail.
3. Black Belts Must Register Their Hands as Weapons
   Martial artists are not walking legal weapons—at least not in any official database.
4. You Swallow Spiders in Your Sleep
   Nope. You’d need a perfect storm of circumstances to even swallow one, and even that’s extremely unlikely.
5. You Have to Wait 48 Hours to Report a Missing Person
   False and dangerous. You can report someone missing immediately, and in some cases, the faster the better.
6. A Penny Dropped from a Skyscraper Could Kill You
   While dramatic, the physics don’t hold up. A penny maxes out at about 30 mph—more of a flick to the head than a fatal impact.
7. We Only Use 10% of Our Brains
   Neuroscientists would like a word. Brain scans show activity across the entire brain, even when we’re resting.
8. Flashing Your Lights at a Car Without Headlights Is a Gang Thing
   This urban legend has zero basis in reality.
9. Shaving Makes Hair Grow Back Thicker
   It might look coarser because the hair is blunt-cut, but shaving doesn’t change its structure.
10. MSG Is Dangerous
    Monosodium glutamate has been demonized for decades, but it’s no worse than table salt for most people.
11. The Earth Is Flat
    Still? Really?
12. Carrots Help You See in the Dark
    This was WWII-era propaganda, not a nutritional fact.
13. “He Who Smelt It, Dealt It”
    A timeless defense.

As for that gum? It might not dissolve in your stomach, but your body’s digestive system is more than capable of moving it along just like any other fiber-rich food. So relax: your 2018 gum is long gone.