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Sitting at your desk, a muscle in your leg palpitates quickly. Or a muscle under your eye flutters. These sudden twitches, known as fasciculation, occur commonly and seem random.

But are these spasms simply minor annoyances? Or are they signs of something more. 

“[A fasciculation] is small and it involves one muscle and it is a local problem,” explains Dr. Jagan Pillai, a neurologist for the Center for Brain Health at Cleveland Clinic.

Fasciculation occurs when a muscle spontaneously becomes excited because of nerve miscommunication. Motor neurons, which live in the spinal cord and base of the brain, send their axons out to tell muscles how to move, but in some situations a disruption occurs, causing fasciculation. Exhaustion, anxiety or depression, nicotine, or too much caffeine can make nerves hyper-excited, disrupting the motor neurons and causing a muscle to flutter wildly.

“Fasciculation is a twitching in the muscles because of abnormal firing of the nerves,” says Dr. Kourosh Rezania, an assistant professor of neurology at the University of Chicago Medical Center.

 “Very often it’s of unclear significance and doesn’t lead to any long term problems.”

Because physicians believe things such as stress and exhaustion cause fasciculation, most solutions are at-home remedies.  

“If [muscle twitches] are really bothersome, the best thing to do is lifestyle modification; get plenty of sleep, exercise, relaxation, and minimize caffeine [consumption],” says Dr. Carlayne Jackson, a professor of neurology at the University of Texas Health Science Center, San Antonio and a member of the American Academy of Neurology.

While the majority of muscle twitches are harmless, fasciculation can be a symptom of other disorders, ranging from very serious to mild. Fasciculation occurring with muscle weakness and atrophy can be a sign ALS, also known as Lou Gehrig’s disease. 

“If [patients] have fasciculation and no weakness, it is unlikely it will have an ominous outcome,” explains Jackson.  

Having frequent fasciculation does not mean that one will develop ALS or any other disease. People with ALS complain more of muscle weakness and pain, Rezania says. 

A less serious, rare condition—known as cramp fasciculation syndrome—causes cramps, pain, fasciculation, and fatigue.

“Cramp fasciculation symptom does not become ALS,” stresses Rezania. “The nerves are excitable and that causes increased symptoms.”

Pillai notes that if patients complain of jerks in their body, doctors must determine the cause of fasciculation—twitches can also be related to diseases such as MS, epilepsy, thyroid disease, or kidney disease, but these disorders almost always have other symptoms associated with them. And physicians must diagnosis whether the movements are fasciculation or myoclonus, which are sudden, involuntary muscle twitches, impacting a group of muscles. Hiccups and hypnic jerks are both forms of myoclonus.  

“[Fasciculation] is commonly noted in normal people, but it could be a sign of a neurological problem. If it is persisting for a long time, it should be taken more seriously than [a twitch] that lasts for a few minutes or an hour,” Pillai says.

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When Lauren Kornacki discovered her father crushed beneath his BMW 525i,  which had slipped off the carjack as he was working on it, the 22-year-old wedged herself under the mid-sized vehicle -- and pulled it off her father.

We hear tales from time to time of people exhibiting superhuman strength in life-and-death emergencies. After experiencing amazement over such a feat, we all wonder: How can a regular person lift something that weighs more than a ton?

Actually, most people "can lift six to seven times their body weight," says Michael Regnier, professor and vice chair of bioengineering at the University of Washington. But most people don’t push themselves so hard, though athletes often push themselves more than most. Fear, fatigue and pain prevent people from attempting feats of amazing strength in daily life, says Dr. Javier Provencio, director of the neurological ICU at Cleveland Clinic.

Regnier, a former world-class weightlifter, has experienced bouts of incredible strength both as an athlete and as someone who helped after an accident. About 20 years ago, Regnier was driving on a Los Angeles freeway when he spotted a wrecked car on the side of the road. The driver sat slumped over his steering wheel so Regnier pulled over to help. It was instinct; he couldn’t fathom leaving the man without doing something. The driver’s door had caved in and Regnier couldn’t get him out any other way—he ripped the door off to pull the man out.

Regnier remembers his hands hurting from cuts he sustained while tearing off the car door, but he doesn’t know what happened with the driver because he left when the EMTs arrived.

Ripping doors off cars or lifting vehicles from people could be considered hysterical strength. Little medical evidence exists about such cases; most of it remains anecdotal.    

Physicians once believed that the adrenaline that flooded the system caused an extra boost to the muscles, allowing people to be stronger. But that’s not quite accurate. Adrenaline certainly primes the body for emergency action, it speeds up the heart and lungs, dilates the blood vessels and releases nutrients, both of which ready the muscles for quick responses.  

And while the adrenaline fueled fight-or-flight reflex spurs people into action, the body’s entire stress response contributes to superhuman strength. Cascades of enzymes and proteins release, helping people sustain the activity.

“Endorphins are very important,” says Provencio. Our bodies release endorphins when we exercise, providing that “runner’s high.” 

These neuropeptides make people feel good and suppress pain as well as providing people with an extra boost to finish their superhuman task.

“[Endorphins] sort of make the brain available to handle these stressful situations. You focus on the task you are doing,” says Regnier. “The endorphins will have a longer lasting affect.” 

While the body’s stress response enables humans to turn into less angry Incredible Hulks, our emotions truly motivate people to attempt such actions.  In most cases, the rescuers believe the victim will die without help. Take 21-year-old Danous Estenor, a University of South Florida football player, who lifted a car off a 34-year-old tow truck driver pinned under a tire in 2011. He believed Pedro Arzola would have perished without his intervention.

“The people who do these things are really under a lot of stress,” says Provencio. “It really touches them personally.” 

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Nightly News

As part of Tony Robbins’ motivational seminar “Unleash the Power Within” participants can opt to walk across a field of hot coals, which can reach temperatures as high as 1,000 degrees Fahrenheit. Firewalking is always an unforgettable experience, but especially so for some firewalkers at Robbins' conference on July 19 -- 21 participants suffered second and third degree burns. 

Yet most people who walk across fire do not suffer from burns -- that's because coals are poor conductors of heat.  

“There is not much energy on the surface of the coals -- as long as you do not linger, [you won’t get burned],” explains Jearl Walker, a professor of physics at Cleveland State University.

“You want to walk at a moderate pace and you do not want to run,” because running kicks up embers, resulting in burns.

Some reports indicate that some of the injured people from the Robbins event hesitated when crossing the fire. Standing on the coals too long or walking across freshly raked coals also increases the chance of sustaining burns.   

Walker, who has firewalked seven times for classes and on his PBS show “Kinetic Karnival,” is one of the few experts on firewalking. While most of his firewalking experiences went off without a hitch, the third time he crossed the coals, an ember got caught under his toes and he carried it across the four feet of hot coals, causing third-degree burns.  

Why would any rational person decide to walk barefoot across fire? It’s simple -- firewalking provides a high.

“(Y)ou meet the challenge and then feel good about yourself. It gives you a rush,” Walker says.

Prior to traversing a bed of hot coals, people step on wet grass, which protects them from burns. (Although Walker admits he is normally so nervous his feet are sweaty enough to provide a layer of moisture.)

The dampness protects the skin because of a phenomenon called the Leidenfrost Effect. Walker says people can easily observe this in the kitchen. If one sprinkles water on a hot skillet, at a temperature of less than 100 degrees Celsius, the water sizzles and evaporates. But if the temperature exceeds 100 degree Celsius, the water spreads, causing a vapor layer, which actually prevents the water from evaporating quickly. This also happens when people with damp (or sweaty) feet walk across the coals: “When you walk over coals [the water] might produce a vapor layer and you avoid a burn because of that,” Walker says.

Also, frequent firewalkers stroll around without shoes to build up calluses on their feet. (Pro tip: avoid pedis prior to a firewalk.)  

“If you get really thick calluses and you burn part of them … you are not going [feel it],” Walker says.

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A group of 13- and 14-year old girls recently fell under a mass trance after attending a hypnotism act at their private high school in Quebec. The inexperienced 20-year-old hypnotist -- who claimed to have had about 14 hours of instruction -- had to call on his instructor to help snap the girls out of it, according to a CBC News report. 

The school principal later apologized to parents and students saying "they didn't know that 14-year-olds were more vulnerable to hypnosis than other people," and noted that all the girls are now fine, a Canadian press account reported.

But some of the girls complained of nausea and headaches shortly after the show, a sign that hypnosis shouldn’t be used as entertainment, says Dr. Joseph Zastrow, president of the American Society of Clinical Hypnosis and a family practitioner in Mooresville, N.C who teaches hypnosis and uses it in his medical practice.

"Stage hypnotists largely set a bad example to the public of what clinical hypnosis can do," says Zastrow. "We find it unethical to use hypnosis in a nonclinical fashion and certainly in the type of setting that it was provided in Canada," he adds. 

Zastrow says the American Society of Clinical Hypnosis provides hypnosis training but only to health professionals who have at least a master's degree  -- to psychologists, social workers, dentists, and doctors -- who will be using it as a tool in their practices. In addition to at least 60 hours of training, these practitioners also need to become board certified in hypnosis in their respective health field.

Using hypnosis as “fun and frolics,” is "like practicing medicine or psychology without a license,” Zastrow suggests, adding that doing hypnosis in groups is difficult to do properly.

There’s no magic to putting someone in a hypnotic state because a trance is a "natural extension of focus and attention," says Zastrow. Many of us are in a form of a trance when we daydream, or drive past our exit on the highway, or when professional athletes compete without being distracted by the crowd. 

By some estimates 5 to 10 percent of people are easily hypnotized and a roughly similar percentage are resistant to trance. The rest of us fall somewhere in between. Young people between the ages of 10 to 18 are at a prime age for responding to hypnotic suggestions and using these skills, says Zastrow.

Medical hypnosis has been most effective for pain control, such as for cancer-related pain, dental procedure pain, or the pain of childbirth, says Zastrow. Studies indicate it can ease symptoms of irritable bowel syndrome, and is effective for about 20 percent of people hoping to quit smoking.

When poorly trained entertainers – the types who make people quack like a duck or sing like Elvis – put teen girls into long deep trances, Zastrow believes "it besmirches the good deeds done every day by professionals using clinical hypnosis." 

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After suffering a brain hemorrhage, 7-year-old Charlotte Neve slipped into a coma. The British girl was unconscious for several days and doctors feared she wouldn’t recover. Her mother, Leila Neve, was at her bedside when Adele’s “Rolling in the Deep” started playing on the radio. Leila and Charlotte often sang the song together and Leila began singing along.

Then something remarkable happened: Charlotte smiled. Within two days, she could speak and get out of bed. Why does music seem to help "awaken" some people from their comas?

“It was a salient stimulus, something that she is familiar with, like [her] name,” says Dr. Emery Neal Brown, professor of anesthesia at Mass General Hospital and Harvard Medical School and professor of computational neuroscience at MIT.

Brown suspects Charlotte recovered some brain functioning prior to hearing the Adele song, but it was imperceptible. When she heard the song, she smiled and eventually woke because it held meaning for her (that's the salient stimulus part).  

“Maybe people have function recovered and we don’t know how to communicate with them,” he says, explaining a salient stimulus varies by person.

“Whenever memories have an emotional context to them, they tend to hold much more power in the brain and tend to be processed differently,” says Dr. Javier Provencio, director of the Neurological Critical Care Unit at Cleveland Clinic.

Robin Gibb of the Bee Gees woke from his coma when his family played music for him — music for a professional musician who sang with his brothers would have deep meaningful connections in the brain, sparking a reaction. But for someone who plays tennis or rides horses, a song might not encourage a response. 

But sometimes, music causes a reaction because the brain processes songs differently than spoken language. In these cases, the region of the brain responsible for song might be working better while the language lags behind.

“We clearly process music and tonal things differently than language. There are patients [who had strokes] who cannot talk but can still sing,” says Provencio.

The left cerebral hemisphere controls language, while the right processes song and music. Patients who have damage in the left might respond better to song.

“They lose the ability to talk and understand. Music therapy is really useful because it is used in the non-dominate hemisphere,” says Dr. James Bernat, professor of neurology and medicine at Geisel School of Medicine at Dartmouth and a member of the American Academy of Neurology.

Music therapists such as Lee Anna Rasar at the University of Wisconsin Eau Claire often use music to try to evoke responses from comatose patients. She notes that songs are most effective “if the music is something they knew before that already had meaning.”

All the physicians agree that doctors still have limited understanding of whether someone will recover from a coma, but if Charlotte wasn’t already healing, she wouldn’t have smiled at the song.

“Even in a coma, it’s quite common that these people improve spontaneously,” says Bernat. “They wake up and start responding. It isn’t outside the range of what is expected that there would be improvement over time.”

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On Thursday evening in Bern, Switzerland, Myanmar’s Nobel Peace Prize award-winner, Aung San Suu Kyi, discontinued her press conference after 15 minutes. Suu Kyi paused the questioning as a sickened look crossed her face. She grabbed a bag and vomited into it. She left the conference apologizing for the sudden eruption, um, interruption.

She began the press conference by noting she felt exhausted and struggled to adjust to the time difference. Can fatigue -- plus a bad case of jet lag -- really make you throw up?    

“A combination of exhaustion and experiencing a big time difference could certainly lead someone to vomit. This may be even more true if they are very warm or under a great deal of stress,” says Dr. Rachel Vreeman via email. Vreeman is co-author of the book “Don’t Swallow your Gum!: Myths, Half-Truths, and Outright Lies About Your Body and Health” and an assistant professor of pediatrics in the Children's Health Services Research Program at the Indiana University School of Medicine.

Exhaustion causes a variety of symptoms, some more common than others. People suffering from a lack of sleep might feel tremors, headache, concentration problems, elevated blood pressure, achy muscles and psychosis.

“Exhaustion can absolutely make someone feel nauseous and even lead to vomiting. Sometimes, the body responds to fatigue -- especially extreme fatigue -- with symptoms of nausea. Stomach upset, including nausea, vomiting, and diarrhea, can also be symptoms of jet lag,” says Vreeman.

Extreme fatigue sparks intervention from two opposing systems in the body -- the parasympathetic nervous system and the sympathetic nervous system. The sympathetic nervous system helps people in tough situations by triggering the flight or fight response, which throws the body into alert mode. The parasympathetic nervous system controls at-rest functions like digestion and salivation.  

“Depending on which system is reacting the most to the stress and fatigue -- your sympathetic system that creates a flight-or-fight response or your parasympathetic system, which causes you to do things like salivate and have relaxed bowels -- you might experience nausea and vomiting in a particular situation,” Vreeman says. 

According to an AP article, Suu Kyi experienced recent bouts of illness when traveling. The slight, 66-year-old political activist felt weak and threw up twice while campaigning for parliament.

Suu Kyi is not alone when it comes to public purging. When George H.W. Bush visited Japan in 1992, he famously spewed on the lap of Prime Minister Kiichi Miyazawa during a state dinner. Bush claimed to be exhausted from an earlier tennis bout and perhaps afflicted by the flu.

Athletes frequently lose their lunches -- some more than others. Pete Sampras and Michael Jordon both spewed on the court, but it seems that former Philadelphia Eagle, Donovan McNabb made blowing chunks a habit. McNabb puked at the end of the fourth quarter during Super Bowl XXXIX. The quarterback said he felt nauseated all game, but teammates claimed McNabb threw up frequently during games and blamed it on exhaustion. 

Vreeman says if a person vomits once because of exhaustion, it doesn’t mean it will occur again. People can prevent the negative effects of exhaustion by sleeping more, staying hydrated, and wearing comfortable clothing. If it seems that jet lag is the problem, people can take sleep aids or melatonin to reduce the impact of time change.

Related:

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You’re staring at your blank computer screen when dots drift into your line of vision. They resemble specks of dust or perhaps clouds or cobwebs. Don’t panic -- you’re not seeing things. You’re witnessing eye floaters, not tricks of the eye or mind.

“Floaters are a part of the normal aging process,” says Dr. Pravin Dugel, managing partner at Retinal Consultants of Arizona in Phoenix.

Eye floaters are fibers that detach from the eye. A hollow cavity filled with a vitreous jelly, composed of 99 percent water and 1 percent collagen, lies in the center of the eye. This gel helps give eyes their round shape and aids in seeing. As we age, the vitreous liquefies and pieces of it begin to release from the back wall of the eye. The debris floats across the field of vision, causing people to see dots, flies, cobwebs, or clouds.

“You can think of [floaters] as UFOs floating in the eye,” explains Dr. Abdhish R. Bhavsar, director of clinical research at the Retina Center of Minnesota. He explains that unlike UFOs, physicians know what floaters are, but like UFOs they often appear differently based on who sees them. 

While it seems that floaters glide across the front of the eye, they’re actually drifting through the eye. It’s the shadow of the fibers reflecting on the retina that people see. 

Although eye floaters don’t occur in everyone, at least 60 percent of people experience them by age 65, says Dugel. Those who have had cataract surgery or have severe nearsightedness might experience eye floaters earlier in life. People who are nearsighted (or myopic) have longer eyeballs, and the vitreous gel stretches more in myopic eyes than in an eye with either normal vision or farsightedness.

Bhavsar notes that sometimes people experience vitreous detaching, but do not see floaters while others see a large number of floaters while the vitreous shedding is minimal.

Even though both doctors stress that eye floaters should not be cause for concern, they do recommend people go for eye exams if there is a sudden explosion in the number of floaters or flashing lights accompany the dots.

“In some people as that jelly peels off it’s like Velcro peeling off … it pulls on the retina and it causes a tear,” Dugel says.

If the retina tears, ophthalmologists can repair it, using lasers or cyrotherapy, which involves freezing, and can prevent the retina from detaching from the eye. If the retina does dislodge, doctors must perform surgery to repair it.

But for most people, floaters are simply an annoyance. In very rare cases, ophthalmologists perform surgery to remove the vitreous, but for majority of patients, the floaters settle to the bottom of the eye after time and cause no other problem. 

“In the absence of all those other medical conditions, [floaters] are a nuisance and they can affect people in varying [degrees],” says Bhavsar.

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Warning: Yellow journalism alert.

When grown men and little boys urinate, occasionally our entire body is abruptly racked with a mysterious, internal blast of cold that makes us visibly shudder from the shoulders down. It typically occurs near the end of the task, lasting roughly one frigid second.

This chill is not discussed, of course, in polite circles -- or even when we return to our buds in the sports bar. So, at no time will you hear: “Dudes, you’ll never guess what just happened to me in the bathroom?” Well … hopefully never.

Yet, we’ve given this sensation a name: the pee shiver. And as the name suggests, depending on a guy’s aim, it can make for messy results. 

So let’s get right to question No. 1.

Why, in the name of Wiz Khalifa (or, if you like, P. Diddy), does this happen?

No leaks were required to obtain this information. We simply turned to Dr. Anish Sheth, author of “What’s My Pee Telling Me?”

“No one knows for certain what the specific trigger for the shivering is,” says Sheth, formerly director of the gastrointestinal motility program at Yale Medical School. But he points to two generally accepted variables to help solve this riddle.

First, the feeling “mostly” is experienced by males. Second, it “occurs most commonly while voiding large amounts of urine,” he says.

Or, to put it as delicately as possible, the icy jolt seems to hit after we’ve really, really had to go. Never after a tiny trickle.

According to Sheth, our parasympathetic nervous system (responsible for “rest-and-digest” functions) lowers the body’s blood pressure “to initiate urination.” One leading theory behind the shudder is that peeing can unleash a reactive response from the body’s sympathetic nervous system (which handles “fight or flight” actions).

On the cellular level, the body is theoretically flushed with catecholamines (which you know better as chemicals like dopamine or hormones like adrenaline). Those are dispatched to help restore or maintain blood pressure, Sheth says. But the microscopic energy bullets “may also trigger the shiver reflect.”

This theory, the author says, best explains “the gender difference as men pee standing up and, therefore, would be more prone to feeling the effects of a lower blood pressure, thereby triggering this exaggerated sympathetic nervous system response.

“Anecdotally,” he adds, “I don’t believe I have ever experienced the post-pee shivers while sitting down.” This would suggest that women don't tend to get them. (Do you? If so, please let us know.)

“I wouldn't know if it's a guy thing or a girl thing because I've never had a conversation with a girl about this – and it's not likely to happen anytime soon,” says stand-up comedian Dan Nainan

“I always wonder: what is that? … Why is it happening?” Nainan adds. “Obviously there is an evolutionary or natural-selection reason for everything. (But) as I'm trying to picture a caveman urinating out in the open, I'm wondering what the necessity of the shivering is.

“I think it tends to happen more in a public bathroom,” he adds. “Could it be some sort of way to warn off nearby enemies or something?”

Wow, comics must have to endure some pretty rough bathrooms.

Bill Briggs is a frequent contributor to msnbc.com and author of “The Third Miracle.”

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Getty Images stock

The fight begins.

Round One: Your field of vision -- maybe a laptop screen, maybe a TV screen -- slowly dissolves from bright and wide to dim and squinty. Your eyelids are drooping.

Round Two: Soft, steady blinks set in, like a referee counting you out. Your lids feel like slabs of cement. In a desperate push, you forcibly ram your bulbs open: a brief, final glare at the fading world.

Round Three: Your brave gaze promptly melts into a haze of lashes. The cement-laden lids now feel like they’re also carrying cement mixers.

 Round Four: You’re out.

That nightly bout -- you versus Morpheus (or, if you’re not into Greek mythology, you versus the Sandman) -- is a simply the last moment of a war of attrition inside the muscles that power your eyelids, including the levator, the Mullers, and the frontalis. Those tiny fibers feel heavy after a day of watching, scanning, looking and gawking. It’s just a matter of muscle fatigue, no different than your biceps feeling spent after a set of curls in the gym.

“Reading – or, like I’ve been doing the past few days, working on the computer – really wears those muscles down like your legs would become tired from walking for a whole day,” says professor Mark A. W. Andrews, professor of physiology at Seton Hill University in Greensburg, Pa. (Before a phone interview with The Body Odd, Andrews had spent three straight days preparing exams for his students).

Your lids can feel extra hefty after days “when you have to concentrate and keep them open a certain amount, “Andrews adds. “It’s even worse when you’re working in a darker environment. Just like an f-stop on a camera (which regulates exposure), you have to make sure your eyes are fully widened, letting all the possible light in.”

This also explains your instinctive attempt to momentarily revive tired eyes -- gently rubbing them with your fingers.

“What feels good after you exercise certain muscles? A massage of sorts,” Andrews says. “That rubbing is going to increase the blood flow in the area and get rid of waste materials that are generated from fatigue. The rubbing washes the waste materials out and into the lymph system.”

What’s more, this is why tired eyes tend to look puffy, he adds: “When you’re using a muscle a lot, there’s a lot of vascular pressure, a lot of blood flowing through.”

In people with anatomically heavier eyelids, Andrews explains, their lid muscles can fatigue even faster than in people with thin lids. Sorry about that, Blake Lively. 

And as we age, many of us acquire “fat pads,” beneath our eyes. This extra tissue makes the heavy-lid sensation “more prevalent” when we're weary, Andrews says. Even worse, at that stage look just as tired as we feel.

Anyway, all this chatter about sleepy eyes is making my eyelidzzzzzzzzzzzzzzzzzzzzzzzzz … Oh no. Round One.

Bill Briggs is a frequent contributor to msnbc.com and author of “The Third Miracle.”

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We ask a lot of weird questions here at The Body Odd. But so do you! Here's our answer to one of your latest queries. Got an inquiring mind? Head over to our Facebook page and ask us your oddest health, medical or human behavior question. We may answer it in an upcoming post.

Today's question: Why is cracking my knuckles so addictive?

The pop! pop! pop! of each cracked knuckle is so sweetly satisfying to you. But it's slowly driving everyone around you completely nuts. You don't remember when you started it, but you can't seem to make yourself stop. Why? "There’s not any hard science to explain why it’s so addictive, but certainly people speculate it’s one of these activities that releases nervous energy," says Dr. Rachel Vreeman, assistant professor of pediatrics at Indiana University School of Medicine and co-author of "Don't Cross Your Eyes ... They'll Get Stuck That Way!"

Some people twirl their hair, some people jiggle their foot up and down -- and some people pop their knuckles. "Many people who do it believe that it feels good," Vreeman says. "They find it to feel good or comfortable, or it even gives them some physical release."

We should note that when you "crack" your knuckles -- you're not actually cracking anything. "That sound you hear is synovial fluid vapor cavities -- or gas bubbles -- in the fluid around your joints. With certain amounts of pressure you can make those bubbles burst." She's making it sound like popping bubble wrap -- no wonder both activities are equally satisfying. 

And, no, cracking your knuckles won't give you arthritis, despite wild rumors you may read on the Internet. Vreeman says in studies of hand function in adults both with and without arthritis, those with arthritis weren't any likelier to be knuckle-crackers. In other words, she says "It doesn’t seem like you’re likely to get arthritis because of your annoying knuckle cracking."

Still, habitual knuckle-popping might lead to some hand discomfort, including swelling, reduced hand strength and even some finger or joint injuries. So, how do you knock it off? 

"Certain things that make you more likely to break your bad habit: coming up with a clear plan. Having some accountability. Telling other people about it," Vreeman says. "From weight loss literature we find that people do better with modifying their eating habits by keeping records -- so keep some record throughout the day how many times a day you did it.

"We also know from sort of the science of habits that it takes ... 28 days to form a habit," Vreeman explains, "so to form an opposite habit probably takes at least that long."

Is there a bad habit you're trying to break in 2012? Let us know how it's going on our Facebook page.

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Manish Swarup / AP file

"Ghost chili" peppers, pictured here at Changpool in the northeastern Indian state of Assam, were recently named the spiciest chili in the world by Guinness World Records

By Katharine Gammon
Life's Little Mysteries 

In a contest that matches humans against some of the world's hottest chili peppers, no one wins. Recently, restaurant in Edinburgh, Scotland, held a competition to eat the extra-hot Kismot Killer curry. Some of the competitive eaters were left writhing on the floor in agony, vomiting and fainting.

According to reports, two British Red Cross workers overseeing the event at the Kismot Indian restaurant in Edinburgh but became overwhelmed by the number of casualties and ambulances were called. Half of the 20 people who took part in the challenge dropped out after witnessing the first diners vomiting, collapsing, sweating and panting.

So what exactly are the health impacts of eating really hot chili peppers? Can eating too much of the spicy stuff kill you?

To answer this question, Life's Little Mysteries turned to one of the experts: Paul Bosland, professor of horticulture at New Mexico State University and director of the Chile Pepper Institute, was responsible for finding the world's hottest chili pepper, the Bhut Jolokia.

Bosland says that chili peppers (or as some call them, chile peppers) can indeed cause death — but most  people's bodies would falter long before they reached that point. "Theoretically, one could eat enough really hot chiles to kill you," he says. "A research study in 1980 calculated that three pounds of extreme chilies in powder form — of something like the Bhut Jolokia — eaten all at once could kill a 150-pound person."

This scenario wouldn't likely have a chance to play out. "However, one's body would react sooner and not allow it to happen," Bosland said. "One would have to eat it all in one sitting," he says. Taken over the course of a year, those three pounds of chilies wouldn't be harmful.

Chili peppers cause the eater's insides to rev up, which can come with some problems. They activate sympathetic nervous system — which helps control most of the body's internal organs — to expend more energy, so the body burns more calories when the same food is eaten with chili peppers. "Eating chili is associated with increases in metabolic rate and thermogenesis," says John Prescott, a professor at Sussex University and editor of the journal Food Quality and Preference. "Capsaicin, the active ingredient in chili, does cause tissue inflammation so the mucosa of the stomach or intestines might be damaged by a sufficiently large dose."

Tissue inflammation could explain why the contestants in the Killer Curry contest said they felt like chainsaws were ripping through their insides. Too much of the spicy stuff can also give you a good case of heartburn.

When it comes to spicy, enough of the hot stuff can cause damage — so eat carefully out there!

Related:

• 10 Weird Things People Do Every Day (and Why)
• Is It Safe to Hold in a Sneeze?
• Why Does Your Nose Run When You Eat Spicy Food?

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