Well, not "everywhere." PMS -- that is, the part where women turn into uncontrollable rage-monsters -- only affects women in Western society.

Anthropologists and psychologists increasingly view PMS as a culture-bound syndrome. This means it's a psychosomatic condition that only occurs within a particular culture -- in this case, Western culture. Sure, women in all times and places have had the physical symptoms ... but not the emotional/psychological ones. In fact, none of the hormonal changes that take place should influence mood at all -- a 2012 meta-analysis of published research found zero correlation between "PMS symptoms" and the actual premenstrual phase of a woman's cycle.

Ekem / Wiki Commons
It's an egg, not a time bomb.

Experts believe that those symptoms may be an expression of the frustration caused by the expectations put on women in Western society. Specifically, the expectation that they be both productive and reproductive members of said society. Women already get tagged with the "hysterical" label if they express emotion in the workplace, so PMS becomes an "express your frustrations for free" card. She didn't call the guy in the next cubicle a dick because she has PMS -- she did it because she does indeed think he's a dick. Saying, or even thinking, that it's the PMS talking is a way to give herself permission to express it.

That's their best guess, anyway.

Wavebreakmedia / iStock
The freedom to rip up his s****y budget plans is positively intoxicating.

To be absolutely clear, they are not saying that PMS is a big scam by Western women to call people dicks once a month with impunity. It's just that everyone conforms to society's expectations to a degree, especially when they give us an opportunity for the kind of release we should have all the time. Slip somebody a nonalcoholic drink and tell them it's full of liquor, and after an hour they'll be running around with their pants on their head. Beyond the placebo effect, you're mainly giving them a chance to let go for a bit.

Every culture has their old wives' tales about how to live longer -- drink eight glasses of water a day, laugh frequently, consume the blood of the innocent. But no one knows for sure why only a lucky few live to an almost supernaturally long age. Hitting the triple digits seemingly happens at random.

Except, that is, on the remote Italian island of Sardinia, where it's practically a given that you'll live past 100. Sardinia's rate of centenarians (people over age 100, not bore-headed mythological creatures) is twice that of the rest of the world. Scientists have attributed the island's fountain of youth to everything from an undiluted gene pool to their pure and simple diet of foods like red wine, fresh olive oil, and organic vegetables -- this latter explanation helped kick off the Mediterranean diet craze.

Jake Whitman / Today
These men are 90 years old, drunk as f**k, and can kick your ass without breaking a grape-scented sweat.

But clearly, it's more than the food, because people around the world eating like Sardinians has mainly resulted in more wine headaches and exactly as many people dying in their 70s. There is no consensus as to why Sardinians live longer than the rest of us. It's a freak occurrence that only happens in one place.

But wait, it also happens in Okinawa, Japan. Nicknamed the "land of the immortals," the city of Okinawa formerly had the highest percentage of centenarians in the world, before being booted off the top of the mountain by Sardinia. Not only do people in Okinawa live longer, but compared to Americans, they have lower rates of dementia, Alzheimer's, and hip fractures. But the average American eats way more Moons Over My Hammys, so it feels like an even trade.

Blake Patterson / Flickr
At least until the super-dementia kicks in and we forget how to eat.

And speaking of Americans, we too can hop on this longevity bandwagon -- but only if we live in the city of Loma Linda, California. Located in San Bernardino County, Loma Lindans regularly live into their 90s and beyond, easily outliving their neighbors in the San Bernardino-Riverside metro area. And Loma Linda has roughly the same median income and racial makeup as said metro area, ruling out genetic and economic factors. Researchers do, however, have some idea as to why its residents live longer, and you could say it's because they pray for good health.

See, Loma Linda was founded in the 19th Century by the Seventh-Day Adventist Church. In addition to proclaiming that the rest of the world goes to church on the wrong day of the week, the religion encourages a plant-based diet and discourages smoking and drinking. The big supermarket in town doesn't even sell meat, seafood, or anything that contains caffeine. So maybe they have discovered the secret to long life, but the rest of us have decided it isn't worth it.

Quest Network
On the other hand, Sardinia's secret -- booze and isolation -- sounds right up our alley.

Meanwhile, on the opposite end of the spectrum ...

Scientists examined everything from Glasgow's weather to Scottish people's penchant for diving headfirst into coin vaults. But Glasgow's weather isn't unique within the UK, and the coin vault thing is sadly specific to wealthy Scottish ducks. One assumption is that the woes of Glaswegians (we didn't make that up) are related to the city's struggling economy, yet residents in similarly unemployed cities like Liverpool and Manchester live 30 percent longer.

More left-field theories range from Glasgow being the center of an epidemic-level vitamin D deficiency to the fact that Scottish people die sooner because ... they're Scottish. Specifically, because Scottish culture tends to produce cantankerous, pessimistic bastards. This explanation is troubling, as it means that even if you move away, the early-death time bomb is still ticking away in your psyche.

David Newell Smith/The Observer
Post-Shithole Stress Syndrome affects ten out of every ten salty Scottish dogs.

Here in the good ol' USA, we have our very own depressing-to-death city: Las Vegas, which has the highest suicide rate of any city in America. While one-to-two odds in Vegas are normally unheard of, unfortunately you're twice as likely to die by suicide there than anywhere else in the U.S. But unlike Glasgow, whose malaise seems to follow its residents no matter where they go, simply being in Vegas is what's driving people to cash in their chips. Lifelong Vegas residents who leave the city briefly see a significantly reduced risk of suicide, while tourists visiting Vegas see an increased chance of it.

Ken Lund/Wiki Commons
Turns out being surrounded by miles of dry, depressing desert and nothing else isn't super-great for the ol' mood.

"Well, duh!" you're probably saying, "It's all those people who lost their life savings at the roulette wheel!" Nope. Despite the long-running trope of the gambler who loses his ass at the casino and then literally checks out at his hotel, the phenomenon has no correlation with gambling. Vegas itself just terminally bums people out.

The most peculiar aspect of the condition is that it almost exclusively affects African-Americans in the Southern U.S. and Afro-Caribbeans in Haiti and the Bahamas (where it affects nearly a quarter of the population). The most obvious theory is that it's caused by the unique stress that comes with living in the inner city (poverty, overcrowding, gangs, all the other bullshit) but, once more, you don't see it in other parts of the world where they have those exact same factors. It's these two distinct populations in these two distinct areas, and nobody has any idea why.

MickyWiswedel / iStock
It's not all earthquakes and devastation's fault, though they certainly don't help.

On a similar, yet even stranger, note ...

Sudden Unexpected Nocturnal Death Syndrome -- or SUNDS -- is a mysterious disease that is killing sleeping men in Thailand, Malaysia, Laos, and other countries throughout Southeast Asia. The syndrome is precisely what the name implies: A person goes to bed and wakes up significantly more dead than they were when they went to sleep.

The men who succumb to this syndrome are all relatively healthy, and there is often no discernible reason why it occurs -- "toxicology, heart disease, sleep apnea and other sleep disorders, genetics, metabolism, and nutrition" have all been ruled out. And you can't outrun sleep death by leaving the region, as the syndrome practically haunts Asian men no matter where they go. For example, in the 1980s, U.S. immigrants of the Hmong ethnic group were frequently sleep-dying without warning.

RamseyCountyMN / Wiki Commons
This is less a town hall meeting and more a dress rehearsal for that guy's funeral.

Despite the best efforts of the scientific and medical communities, no one has any idea why SUNDS only affects men in the prime of their lives, or how to cure it. The best guess comes from Shelley Adler, a professor at the University of California, San Francisco, who postulates that the deaths stem from the Hmong belief that a nightmare is an actual visit from an evil being intent on murdering the s**t out of you in your sleep. That's right: Science's most plausible explanation for SUNDS is Thai Freddy Krueger.

Researchers examined 207 Middle-East-born Islamic terrorists who pursued higher education, and found that a whopping 45 percent of them studied engineering. For perspective, regular, law-abiding college students in 19 Middle Eastern countries were also examined, and only 12 percent studied engineering. And this isn't a uniquely geographical phenomenon. Of 71 Muslim terrorists who grew up in Western countries, 32 of them studied engineering.

"Oh," you figure, "So Jihadists probably target and recruit these populations because they'll be useful." That would make sense on the surface, since an engineer could help a group of terrorists create explosive devices or craft attractive recruitment websites. Well, researchers looked into it and found that in most instances, the engineers were not recruited -- they joined the groups of their own accord. Also, of 228 terrorist plots reviewed, a mere 15 percent of the engineers crafted the incendiary devices involved. Their engineering skills weren't even put to use.

Olichel/Pixabay
So yet another example of your diploma being worthless for the career you end up in.

"Okay," you think, "Maybe there's some kind of other weird connection between extremist Islam and the type of Muslims who pursue those fields?" Not really -- it turns out that other extremist groups, such as white supremacists and neo-Stalinists, also feature a disproportionate number of engineers. What the f**k?

Is there something about that field that attracts angry, antisocial types? Is there something about that field that turns normal kids into angry, antisocial types? Is it all a big coincidence? Nobody knows.

d97jro / pixabay
Until we do, we should probably cover MIT and all who attend in a thick blanket of cement. Just in case.

Check out Patrick Coyne's blog for more funny articles of this ilk.

For more bizarre phenomenon that happens in only certain locations, check out 5 Mental Disorders That Only Occur In One Place On Earth and 6 Mental Illnesses That Only Happen In One Place On Earth.

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