5 Popular Safety Measures That Don't Make You Any Safer

And that wasn't an isolated incident. Seven international flights have been diverted, at a cost of roughly $6.25 million, and countless flights and passengers have been delayed. Homeland Security Affairs estimates the total cost of the list to our government at $100 million a year. But hey, fighting terror isn't cheap. At least no terrorists are getting on planes!

Well, unless you count those 11 terrorists in England with the sophisticated plot to blow up planes with liquid explosives. You know, the ones who are the reason you can't take a child-sized bottle of shampoo onto the plane any more. None of them managed to stumble onto the no fly list ... even though they'd been under surveillance for more than a year.

It turns out it's even possible to beat the no fly list even if the authorities aren't terribly incompetent. All a potential terrorist would need to do is use a false name and get a fake ID. Security experts have also created boarding pass generators on the Internet to prove how worthless the whole system is. CBS was able to purchase tickets on three airlines and bypass security in five airports using a $150 fake license.

Not that most terror-inclined individuals would even need a fake ID. The no fly list is filled with tons of dead people and foreign politicians along with small children and Marine veterans but is surprisingly light on real terrorists. Christmas Day underwear bomber Umar Farouk Abdulmutallab bought a one-way flight from Lagos to Detroit by way of Amsterdam and paid in cash. Umar's own father called US officials several times in the months before the flight, warning them that his son had terrorist-y plans. Umar, who didn't get the plane to crash because the bomb in his pants wouldn't go off, never made it onto the no fly list.

But that's OK, since said underwear bomber has prompted governments around the world to install full-body scanners in their airports. You know, the ones that let the operator see your genitals. In late 2009 the TSA ordered $165 million worth of full body scanners, and countries like Canada have followed suit. But it's worth it, to stop terrorists like Umar Farouk Abdulmutallab! Only, they wouldn't have stopped him. Let's quote Rafi Sela, former chief security officer for the Israel Airport Authority:

"I don't know why everybody is running to buy these expensive and useless machines. I can overcome the body scanners with enough explosives to bring down a Boeing 747,"

These scanners would also have done nothing to detect the failed 2006 liquid bomb plot or the 2005 London train bombing. They can't even detect objects stuffed inside the body. For a visual example, check out this video of a rotund German man besting a full-body scanner. The machine caught his pocket knife, cell phone and microphone...

...but it didn't notice the armload of chemical bomb components he was carrying.

This fits in with what the Highway Loss Data Institute learned about anti-lock brakes. A 10 year study showed no reduction in the frequency or severity of crashes due to anti-lock brakes. A person in an ABS vehicle actually has a 45 percent greater chance of dying in a single-vehicle crash than someone without ABS. Science's explanation? Unskilled drivers driving more aggressively thanks to their false sense of security.

Likewise, there are multiple studies showing that bicycle helmets, in the long run, don't actually reduce the number of injuries. In 2006 a researcher in Bath, England posted up the results of a study showing that when bicyclists wear safety equipment like helmets, people in cars are more likely to hit them. A scientist/test subject found that motorists came an average of 3.35 inches closer to his bike when he rode protected. The sight of the safety gear turned off the common sense part of their brain.

Still, you'd think that in the long run, there'd have to be health benefits to head protection. After all, some countries, like Australia, have made helmets mandatory for all cyclists. A bunch of states in the U.S. have bike helmet laws, and the fight for helmet laws in other states rages on. Some people think it's weird that the government can tell you what kind of hat to wear during a certain activity, but at least bike fatalities have gone down. They have gone down, right?

Not according to science. Recent studies from Australia suggest that mandatory helmet laws have the opposite effect. Between 1982 and 1989 -- prior to the helmet laws -- the country saw its number of cyclists double (bicycles actually give pedestrians a decent chance of outrunning the crocodiles and flying jellyfish). You'd expect bike-related injuries and fatalities to have shot up during the same period.

Instead, they dropped -- deaths plummeted by 48 percent, while injuries fell 33 percent. This seems a little counter-intuitive until you account for human behavior. More people riding bikes leads to motorists who get used to sharing the road with them. But then, in 1992, they passed the laws making bike helmets mandatory. It was a disaster. 1995 and 1996 saw higher numbers of cyclist head injuries than any year prior to the law's passage.

How is that possible? Well, the fashion consequences of mandatory helmets caused the women of Australia to stop cycling. Apparently they valued the hair on their head more than the brain inside it. Since there weren't any girls to impress, the boys stopped cycling too.

Cyclists are rarer, motorists are less likely to be on the lookout for them, so there are more accidents. And -- to make it even worse -- you lose the health benefits you were getting from cycling. In total, Macquarie University found that Australia's helmet laws cause as much as half a billion dollars in health-related costs every year. It doesn't matter what kind of data you get from a helmeted crash test dummy; a real human just doesn't want to look like a dork.

Don't get us wrong; last year 8,650 people in the United States died of melanoma, the deadliest type of skin cancer. Summertime PSAs and middle school health teachers lead us to believe that we could avoid the same grisly fate by slathering on enough high SPF sunscreen to make us look like we fell into the mayonnaise vat they keep behind every Burger King.

Well, while it's true that tanning is about as retarded as drinking radium, the idea that sunscreen will protect you from skin cancer is wishful thinking. A study released in May 2010 showed that 92 percent of sunscreen lotions on the market are completely ineffective.

Worse, one common sunscreen additive, retinyl palmitate, has been found by the FDA to speed up skin lesions and act as a photocarcinogenic. Oxybenzone, a chemical you'll find in Coppertone and a ton of other big-name sunblocks, has been linked to contact eczema and breast cancer. But hey, at least you'll be safe from melanoma!

Unless you aren't. If you listened in health class, you know to look for a sunscreen with an SPF above 30. Unfortunately, SPF only measures the sunscreen's ability to block UVB radiation, not UVA radiation. This is a problem because it's actually UVA radiation that causes skin cancer. This is where the confusion sets in over whether you're using sunscreen to prevent cancer, or sunburn. Most people are worried about the latter, even though all the warnings we hear are about the former.

It gets worse. The FDA has yet to create any regulations for how sunscreens are allowed to indicate their UVA protection. As a result, tons of sunscreen manufacturers have started marketing their products as having "broadspectrum" protection. This would seem to indicate that the sunscreen protects you against both types of ray, but it is actually a completely meaningless marketing term.

Maybe we should apologize to the spray-on tan crowd after all.

Young women don't routinely receive mammograms, and the thinking was that the early notice provided by self-exams would save lives (and breasts). Then some scientists decided to actually test the benefits of medical boob-fondling (our No. 2 pick). In 2008, they published the results of two massive mammary studies encompassing a staggering 388,500 Russian and Chinese women between 30 and 66.

One group of women was not taught or urged to perform examinations. The other women received detailed training and regular refresher classes, which we're guessing were hosted in some sort of large sexodrome filled with pillows and dotted with open bars.

After 10 years of intensive, slightly creepy research the scientists found ... no difference in cancer survival rates between the two groups. We know what you're thinking: Sure, self-exams don't make anyone safer, but they sure as hell can't hurt! They're probably good for your blood pressure or ... something.

You might think that, but you would be wrong. It turns out that the women who do self-examinations are almost twice as likely to get unnecessary biopsies. So basically, you're no less likely to die from cancer, but you're way more likely to have someone stick a knife in your chest. Up to you, ladies.

About 11 percent of Americans in the West and 6.8 percent in the South live in gated developments. High membership dues and expensive housing keep the "riff-raff" from moving in next door, while high walls and a security guard keep them from wandering in off the street, drinking the wrong types of alcohol and leering at women joggers. Sure, it's a little paranoid. But at least people in gated communities gain comfort and tangible safety benefits without hurting anyone else. It's like a guard dog you don't have to feed or replace every 10 years.

Unfortunately, science is finding that the chief benefits of gated-community living are illusory at best. Preliminary research finds that "crimes such as burglary drop in the first year or so of gating, but then rise back to the level of the areas outside." The president of research for the National Association of Home Builders found studies indicating "no differences" in crime between gated and non-gated communities. The City of Miami noted that "the long-term crime rate is at best only marginally altered."

The key is to realize how minimal the security actually is. You're not living behind a Simpsons movie-style dome, protected by your own personal military. You've got a gate, maybe with an electronic code, or maybe with a security guard making barely over minimum wage. In both cases, you can't keep everyone out -- friends, family members, landscaping crews, pizza delivery drivers, all have to be able to pass in and out. The system will always have to allow a certain number of strangers in. Meanwhile, the burglars in the area know that those houses behind the gates have all the nicest stuff -- you're announcing that just by living there -- and that it's not exactly freaking Fort Knox.

And if something bad does happen in your gated paradise? Rescue workers often have issues getting past unmanned security gates and maneuvering bulky emergency vehicles through them. This increases ambulance response time, which can kill you just as dead as the PCP-raging vandals lying in wait outside your fancy walls.

As it turns out, gated communities aren't even good for the illusion of security. Multiple studies in the U.S. and the U.K. show that "residents do not necessarily experience a reduced sense of fear after moving to a gated development. In fact, people can become more fearful and anxious about leaving the safety of their community." Fences have that effect. First you like them, then you feel naked without them.

Yeah, we're thinking you'd be better off with a big dog.

For more ideas that didn't work out so well, check out The 5 Most Popular Safety Laws (That Don't Work) and 5 Retarded Health Campaigns That Backfired (Hilariously).

And stop by Linkstorm to see how DOB's attempt at Match.com hilariously failed.

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