# What Urban Myths seem to hold on for years or decades even when disproven **URL:** \ **Category:** Miscellaneous and Personal Stuff I Must Share\ **Created:** [June 12, 2026, 7:02pm UTC](https://boards.straightdope.com/t/what-urban-myths-seem-to-hold-on-for-years-or-decades-even-when-disproven/1030852 "2026-06-12T19:02:02Z")\ **Posts on this page:** 20\ **Page:** 1
**Author:** ![Cartooniverse](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/cartooniverse/32/3084_2.png) [@Cartooniverse](https://boards.straightdope.com/u/Cartooniverse)\ **Post date:** [June 12, 2026, 7:02pm UTC](https://boards.straightdope.com/t/what-urban-myths-seem-to-hold-on-for-years-or-decades-even-when-disproven/1030852/1 "2026-06-12T19:02:02Z")
I’m mindful of the [Kitty Genovese murder](https://en.wikipedia.org/wiki/Murder_of_Kitty_Genovese) and the subsequent social reaction known as the [bystander effect](https://en.wikipedia.org/wiki/Bystander_effect). As the decades progressed, this situation got turned upside down. 38 people did not in fact witness the murder. And, more importantly, several people did call the NYPD. (Claims that they called 911 are impossible: The New York City Police Department did not implement 911 systems until 4 years after the Genovese murder). So. People held onto this HARD. When I moved to NYC in 1981, this was given as fact. Even after the NYT article debunking the “facts”, many simply didn’t want to let go of the idea that people living near her apartment- and by association, all New Yorkers and/ or all humanity- would rather watch a woman die and do nothing than get involved or call the authorities. There have been other “factual” situations that people hold onto hard after they are debunked. What are they? ---
**Author:** ![Czarcasm](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/czarcasm/32/4050_2.png) [@Czarcasm](https://boards.straightdope.com/u/Czarcasm)\ **Post date:** [June 12, 2026, 7:06pm UTC](https://boards.straightdope.com/t/what-urban-myths-seem-to-hold-on-for-years-or-decades-even-when-disproven/1030852/2 "2026-06-12T19:06:38Z")
The myth that we only used 10% of our brains. ---
**Author:** ![Fretful\_Porpentine](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/fretful_porpentine/32/2873_2.png) [@Fretful\_Porpentine](https://boards.straightdope.com/u/Fretful_Porpentine)\ **Post date:** [June 12, 2026, 7:09pm UTC](https://boards.straightdope.com/t/what-urban-myths-seem-to-hold-on-for-years-or-decades-even-when-disproven/1030852/3 "2026-06-12T19:09:43Z")
I’m not sure this counts as an urban myth, but the education school at my university is _still_ teaching students about “learning styles,” despite abundant evidence that they are [not a thing](https://www.in-mind.org/article/learning-styles-why-they-dont-exist-but-still-persist). ---
**Author:** ![Ponderoid](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/ponderoid/32/19221_2.png) [@Ponderoid](https://boards.straightdope.com/u/Ponderoid)\ **Post date:** [June 12, 2026, 7:10pm UTC](https://boards.straightdope.com/t/what-urban-myths-seem-to-hold-on-for-years-or-decades-even-when-disproven/1030852/4 "2026-06-12T19:10:20Z")
Yeah, most evidence shows it’s a lot less than that. \*rimshot\* I’ll see myself out. 🥁 🧠 ---
**Author:** ![Filbert](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/filbert/32/3433_2.png) [@Filbert](https://boards.straightdope.com/u/Filbert)\ **Post date:** [June 12, 2026, 7:34pm UTC](https://boards.straightdope.com/t/what-urban-myths-seem-to-hold-on-for-years-or-decades-even-when-disproven/1030852/5 "2026-06-12T19:34:00Z")
I’ve heard the myth that women sync menstrual cycles with those they’re close to/living with with from a medical doctor, as well as multiple other people, all of whom were completely convinced it was a real phenomenon. It’s nonsense. The paper that originally demonstrated the ‘effect’ was retracted when it was shown that they calculated the random odds incorrectly. Attempts to investigate the ‘effect’, even in places like nunneries, female only boarding schools and women’s prisons, where groups of women lived together in close contact for years, however isolated, have found no evidence of menstrual synchronisation. It’s just what happens when you get a bunch of things cycling on a similar but not identical timescale, like the indicators on your car and the car in front of you that’s also turning. They go in and out of synch. But still, the myth persists… ---
**Author:** ![Q.Q.Switcheroo](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/q.q.switcheroo/32/5713_2.png) [@Q.Q.Switcheroo](https://boards.straightdope.com/u/Q.Q.Switcheroo)\ **Post date:** [June 12, 2026, 8:14pm UTC](https://boards.straightdope.com/t/what-urban-myths-seem-to-hold-on-for-years-or-decades-even-when-disproven/1030852/6 "2026-06-12T20:14:20Z")
“People in the Middle Ages only lived into their 30s.” No, it was the _average life expectancy_ that skewed young because of all the deaths in infancy and childhood. “Charles Dickens was paid by the word.” No, he was paid by the installment. ---
**Author:** ![ricepad](https://avatars.discourse-cdn.com/v4/letter/r/b38774/32.png) [@ricepad](https://boards.straightdope.com/u/ricepad)\ **Post date:** [June 12, 2026, 8:15pm UTC](https://boards.straightdope.com/t/what-urban-myths-seem-to-hold-on-for-years-or-decades-even-when-disproven/1030852/7 "2026-06-12T20:15:54Z")
MSG/Chinese Restaurant Syndrome causes headaches. ---
**Author:** ![Q.Q.Switcheroo](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/q.q.switcheroo/32/5713_2.png) [@Q.Q.Switcheroo](https://boards.straightdope.com/u/Q.Q.Switcheroo)\ **Post date:** [June 12, 2026, 8:17pm UTC](https://boards.straightdope.com/t/what-urban-myths-seem-to-hold-on-for-years-or-decades-even-when-disproven/1030852/8 "2026-06-12T20:17:19Z")
And “cold weather causes colds.” ---
**Author:** ![Moriarty](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/moriarty/32/49_2.png) [@Moriarty](https://boards.straightdope.com/u/Moriarty)\ **Post date:** [June 12, 2026, 8:18pm UTC](https://boards.straightdope.com/t/what-urban-myths-seem-to-hold-on-for-years-or-decades-even-when-disproven/1030852/9 "2026-06-12T20:18:49Z")
> [@Q.Q.Switcheroo](#): > > “People in the Middle Ages only lived into their 30s.” “And never bathed” > **[I assure you, medieval people bathed.](https://going-medieval.com/2019/08/02/i-assure-you-medieval-people-bathed/)** > > I can’t believe I have to write this down right now, but my dear friends, medieval people bathed regularly. Yes. I assure you. I am very serious. It is true. In fact, medieval people loved a bath a… Can I add the JFK assassination to this list? There’s a persistent myth that there are “a lot of questions left unanswered”. There aren’t. ---
**Author:** ![snowthx](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/snowthx/32/10660_2.png) [@snowthx](https://boards.straightdope.com/u/snowthx)\ **Post date:** [June 12, 2026, 8:24pm UTC](https://boards.straightdope.com/t/what-urban-myths-seem-to-hold-on-for-years-or-decades-even-when-disproven/1030852/10 "2026-06-12T20:24:53Z")
Swimming less than 30 minutes after eating a meal. ---
**Author:** ![Crafter\_Man](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/crafter_man/32/458_2.png) [@Crafter\_Man](https://boards.straightdope.com/u/Crafter_Man)\ **Post date:** [June 12, 2026, 8:26pm UTC](https://boards.straightdope.com/t/what-urban-myths-seem-to-hold-on-for-years-or-decades-even-when-disproven/1030852/11 "2026-06-12T20:26:48Z")
Yea, we were told it causes cramps, which is nonsense. Just thought of one: cracking knuckles causes arthritis. ---
**Author:** ![Q.Q.Switcheroo](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/q.q.switcheroo/32/5713_2.png) [@Q.Q.Switcheroo](https://boards.straightdope.com/u/Q.Q.Switcheroo)\ **Post date:** [June 12, 2026, 8:27pm UTC](https://boards.straightdope.com/t/what-urban-myths-seem-to-hold-on-for-years-or-decades-even-when-disproven/1030852/12 "2026-06-12T20:27:39Z")
“Shaking a Polaroid photo makes it develop faster.” (This one at least has a forgivable origin story: early Polaroids came out of the camera with a liquid coating, which you would air-dry by shaking the photo.) ---
**Author:** ![Velocity](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/velocity/32/18006_2.png) [@Velocity](https://boards.straightdope.com/u/Velocity)\ **Post date:** [June 12, 2026, 8:35pm UTC](https://boards.straightdope.com/t/what-urban-myths-seem-to-hold-on-for-years-or-decades-even-when-disproven/1030852/13 "2026-06-12T20:35:36Z")
The most believable myths seem to all center around personal safety, since that’s what holds the highest stakes for people, and hence the hardest to shake. The OP already shared one example, the myth that 38 people somehow heard a murder happening and did nothing. Another myth that has a lot of holding power is anything that goes contrary to the majority or establishment view, because it gives the “well, actually” sort of contrarian pleasure. One myth being that it’s safer to not wear a seat belt than to wear one, because either 1) it’s safer to be thrown out of the vehicle (not true) or 2) a seatbelt can prevent escape in the event of water or fire (maybe true, but still dwarfed by the lives saved by wearing seatbelts.) ---
**Author:** ![don\_t\_ask](https://avatars.discourse-cdn.com/v4/letter/d/e68b1a/32.png) [@don\_t\_ask](https://boards.straightdope.com/u/don_t_ask)\ **Post date:** [June 12, 2026, 9:04pm UTC](https://boards.straightdope.com/t/what-urban-myths-seem-to-hold-on-for-years-or-decades-even-when-disproven/1030852/14 "2026-06-12T21:04:15Z")
The myth that brainstorming is an effective method for coming up with solutions to problems was proven to be false almost as soon as it was proposed. It is not only not very good it actively hinders finding good solutions. Every time one was foisted on us at work I would point this out and show people the references. Doesn’t seem to happen any more. At least not in any meeting that I am in. ---
**Author:** ![Llama\_Llogophile](https://avatars.discourse-cdn.com/v4/letter/l/49beb7/32.png) [@Llama\_Llogophile](https://boards.straightdope.com/u/Llama_Llogophile)\ **Post date:** [June 12, 2026, 9:07pm UTC](https://boards.straightdope.com/t/what-urban-myths-seem-to-hold-on-for-years-or-decades-even-when-disproven/1030852/15 "2026-06-12T21:07:52Z")
> **[FACT CHECK: NASA's 'Astronaut Pen'](https://www.snopes.com/fact-check/the-write-stuff/)** > > Space race legend claims NASA spent millions of dollars developing an 'astronaut pen' that would work in outer space, while the Soviets solved the same problem by simply using pencils. Can’t tell you how many times I’ve had to tell people this isn’t true. ---
**Author:** ![griffin1977](https://avatars.discourse-cdn.com/v4/letter/g/977dab/32.png) [@griffin1977](https://boards.straightdope.com/u/griffin1977)\ **Post date:** [June 12, 2026, 9:08pm UTC](https://boards.straightdope.com/t/what-urban-myths-seem-to-hold-on-for-years-or-decades-even-when-disproven/1030852/16 "2026-06-12T21:08:43Z")
“Shout fire not rape” it’s not true and the advice actually predates the modern city ([it’s from the pre-modern days of the city watch in medieval cities](https://boards.straightdope.com/t/origin-of-dont-yell-help-yell-fire/961051/7)) ---
**Author:** ![solost](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/solost/32/11776_2.png) [@solost](https://boards.straightdope.com/u/solost)\ **Post date:** [June 12, 2026, 9:53pm UTC](https://boards.straightdope.com/t/what-urban-myths-seem-to-hold-on-for-years-or-decades-even-when-disproven/1030852/17 "2026-06-12T21:53:09Z")
The myth that vaccines cause autism. Based on a [faked 1998 study](https://cdn.kingcounty.gov/-/media/king-county/depts/dph/documents/health-safety/health-programs-services/immunizations/autism-myth/vaccines-autism-myth-en.pdf) and completely discredited, yet the myth stubbornly persists to this day. ---
**Author:** ![AHunter3](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/ahunter3/32/368_2.png) [@AHunter3](https://boards.straightdope.com/u/AHunter3)\ **Post date:** [June 12, 2026, 9:53pm UTC](https://boards.straightdope.com/t/what-urban-myths-seem-to-hold-on-for-years-or-decades-even-when-disproven/1030852/18 "2026-06-12T21:53:44Z")
That everybody needs to drink 64 ounces of water daily. ---
**Author:** ![Dallas\_Jones](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/dallas_jones/32/3277_2.png) [@Dallas\_Jones](https://boards.straightdope.com/u/Dallas_Jones)\ **Post date:** [June 12, 2026, 9:59pm UTC](https://boards.straightdope.com/t/what-urban-myths-seem-to-hold-on-for-years-or-decades-even-when-disproven/1030852/19 "2026-06-12T21:59:04Z")
> [@Czarcasm](#): > > The myth that we only used 10% of our brains. I still can’t stand Scarlett Johansson since that stupid Lucy movie came out. ---
**Author:** ![Treppenwitz](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/treppenwitz/32/3445_2.png) [@Treppenwitz](https://boards.straightdope.com/u/Treppenwitz)\ **Post date:** [June 12, 2026, 10:17pm UTC](https://boards.straightdope.com/t/what-urban-myths-seem-to-hold-on-for-years-or-decades-even-when-disproven/1030852/20 "2026-06-12T22:17:12Z")
> [@Velocity](#): > > One myth being that it’s safer to not wear a seat belt than to wear one, because either 1) it’s safer to be thrown out of the vehicle (not true) or 2) a seatbelt can prevent escape in the event of water or fire (maybe true, but still dwarfed by the lives saved by wearing seatbelts.) Is it? When the UK government decided to introduce seatbelts, they commissioned the Isles Report ( you can find it on the web) to prove that they were safer. The report surveyed European countries which had introduced seatbelts and concluded no effect. (Suppressed by the government and introduced anyway). Ahh… that’s no effect for drivers - because of a phenomenon called risk homeostasis. People drive to an acceptable level of risk - for themselves. So seatbelts ( the Isles report found) have no benefit for drivers but (it is inferred, and is undoubtedly true) make roads more dangerous for everyone else. Suggested reading: Tullock Spike. j ETA: posting on my phone late at night in Brittany. May include minor errors or nuts. [Next page](https://boards.straightdope.com/t/what-urban-myths-seem-to-hold-on-for-years-or-decades-even-when-disproven/1030852.md?page=2)