What happens to your body when you play video games for hours

Video games are awesome. But playing video games too much? That can be a bad thing (or a good thing!), depending on how it breaks out.

There are cases from all over the world of gamers playing too much for too long, and not surviving to actually reach the end credits. Video game addiction is a real thing, and like most good things in the world, it all comes down to pacing and moderation. Too much of anything, from water to sleep, can take you down in certain cases.

But despite the sometimes tragic effects, video games aren't all bad. First off, they're crazy fun. Second, they can improve everything from critical thinking skills to hand-eye coordination in the right context. Heck, they can even make your brain stronger at times. So let's dig into the good, the bad, and the ugly of going into the deep end of video gaming.

You can die of thrombosis

Marathon gaming sessions aren't uncommon. But when it starts to threaten your life? Yeah, that might be taking things a bit too far. A condition called deep vein thrombosis can result from frequently sitting still for too long. One British gamer died of blood clots probably formed by thrombosis after he built a lifestyle of frequent, 12-hour gaming sessions. And a New Zealand gamer went to the hospital with life-threatening blood clots in his legs after playing his PlayStation for four days on vacation.

The condition, sometimes known as "economy class syndrome," typically affects travelers of extremely long-haul flights (since there's nowhere to move around, which is where the phrase was coined). It involves blood clots that can form due to prolonged immobility or an extreme lack of physical activity.

Your heart can fail, and you can die

As CNN reports, a 32-year-old man in Hong Kong was found dead at an internet cafe following a nonstop, three-day gaming binge. The man entered a Hong Kong internet cafe on January 6, 2015, to start playing — and he was found dead by an employee on January 8. The cause of death? Cardiac failure, largely caused by immobility, cold temperatures, and utter exhaustion from lack of sleep. Employees reported he would often stay there for days on end to play, and news outlets note the other gamers at the cafe were unfazed by the paramedics and police who responded to the scene when the man was discovered. Staying awake for days on end puts an extreme strain on your body, and if you're in poor health already, it can prove too much pressure for your heart.

You can develop Nintendonitis

Even if you do take breaks and keep your body active between gaming sessions, the repetition of using a controller for hours, days, weeks, months, and years on end can still take a toll. Gaming typically requires a lot of repetitive motion with your thumbs and fingers, and the BBC reported in 2003 that some players can develop repetitive strain injuries (aka Nintendonitis) because of it. The condition happens when you repeatedly do the same motion over and over (e.g., furiously punching the same button to frag your buddies). It typically affects the wrists and hands but can move up to forearms and elbows depending on the person and the playing style.

You could mess up your lower back

A 1999 study looked at lower back pain in school children, and how it could correlate to different things such as watching TV and playing video games. The report, published in the European Spine Journal, noted video game playing can connect to back pain. Here's an excerpt from the report: "There was significantly more (lower back pain) in children who reported playing video games for more than 2 h per day, but this was not so for television watchers. The visual analogue scales concerning general well-being were all very significantly correlated with self-reported (lower back pain), with children who reported (lower back pain) being more tired, less happy, and worse sleepers."

So if you must play, at least fix your posture.

You can damage your eyes

It should not surprise you to learn that staring at screens (whether TVs, computers, phones, or tablets) for hours on end is not great for your eyes. Called computer vision syndrome (CVS), the condition affects those who spend several hours looking at screens. It can cause a wide range of problems, most commonly led by eye strain and eye pain. These problems can be exacerbated by low light and bad posture, so if you're settling in for a marathon gaming session, at least make sure you have an ergonomic chair and good lighting. Every little bit counts.

It might literally alter your brain

If you play video games enough, it can start to mess with your mind. Literally. A study published in Translational Psychiatry shows that frequent gaming might alter your brain. Put simply, children who played more than nine hours of video games each week had much larger reward centers in their brains, which could make their brains want to play more video games. The study looked at brain scans of more than 150 14-year-olds. The report noted the hardcore gamer group showed "larger volume in the left striatum, a brain area involved in risk and reward processing. In addition, the frequent gamers showed more activity in the ventral striatum when losing money during a gambling task."

If you have epilepsy, it can trigger seizures

If you're prone to seizures, it's a good idea to be careful with your gaming sessions. As a 1994 report published by the National Institutes of Health noted, the majority of patients with epileptic seizures in a small study suffered seizures while playing video games. Factors that can contribute to seizures include photosensitivity, intermittent photic stimulation, and more. For 27 of the 35 seizure patients in that 1994 study, their first seizure came while playing video games. It's important to note that games have changed a lot since 1994. There are now standards in place to guard against these sorts of triggers, although publishers might not always meet those standards.

It could make you more prone to obesity

Like the Wii before it, accessories like Xbox Kinect and Playstation Move (plus VR tech such as Oculus) are starting to push the boundaries as far as what it means to "play" a video game. But for the most part, it still means kicking back on the couch and punching buttons. Turns out that sitting around for hours on end with minimal movement can make you more susceptible to health issues associated with obesity.

The Pittsburgh Post-Gazette reported on a boatload of studies in 2012, with many of the results largely mixed. Some indicated that active video games (e.g., sports games, boxing, etc.) can have the health effect of a slow walk. Other studies found that those who play video games a lot are more likely to develop obesity from the sedentary lifestyle. The best approach? Try to mix in a little exercise and healthy snacks every few levels.

You can literally become addicted

Do anything long enough, and it can become a very strong habit that is hard to break. The same applies to video games. CNN recently reported on a study by Douglas Gentile, a psychologist at Iowa State University, who has been tracking video game players for decades. According to his findings, approximately 8.5 percent of children who play video games in the United States are addicted. Those statistics held up in several other countries, too. Gentile said the estimates can vary, but most studies found that 4-10 percent of children were classified as "addicted" to video games.

So what's the cause of video game addiction? Gentile broke it down to what he calls the ABCs: "The A Is Autonomy, we like to feel we're in control. B is Belonging, we like to feel connected to other people. And the C is Competence, we like to feel that we're good at what we do." As anyone who has ever fist-pumped after finally beating the last castle on Mario or thrown a controller at the TV over an interception in Madden can attest, video games can drive real emotions. Psychologist Mark Griffiths, director of the International Gaming Research Unit at Nottingham Trent University, added that the addiction can also be related to the constant rewards built into video games, from hitting high scores to merely the sense of accomplishment.

It can make your brain stronger

We've already looked at how video games can change your brain, but with the right amount and types of games, it can also make it stronger. According to The Huffington Post, a 2013 study found that the "areas in the brain responsible for spatial navigation, memory formation, strategic planning and fine motor skills in the hands" could all be positively impacted by video games. This makes sense, because most video games aren't easy and take some work to master. They also push you to think strategically. (Just try to beat a Metal Gear game by barreling in guns blazing.) Looking beyond just those perks, the study noted there could be great potential in using video games as a form of therapy for patients who suffer from mental disorders, ranging from Alzheimer's to schizophrenia.

"While previous studies have shown differences in brain structure of video gamers, the present study can demonstrate the direct causal link between video gaming and a volumetric brain increase," study leader Simone Kühn said. "This proves that specific brain regions can be trained by means of video games."

They can make your hand-eye coordination sharper

You have to be fast to be a good gamer, and not surprisingly, those skills can translate out in very positive ways beyond video games. In 2014, Tech Times reported on a study that found playing action video games "regularly helps gamers learn new sensorimotor skills, especially eye and hand coordination." These skills are similar to what it takes to successfully ride a bicycle without falling over, by using your sight and coordinating your muscles to complete a task successfully. Turns out fragging your buddy or pulling off the perfect Hail Mary could go a long way toward honing those skills. Career-wise, the report notes those abilities can come in handy if you want to be surgeon (since you'll certainly need steady hands). So remember that next time you're flying through Halo, you're also prepping for med school.

They can actually make you more social

The loner sitting in his room playing video games is an old cliche, but these days, it's a woefully outdated one. Online gaming has managed to connect people in ways we never could've dreamed of decades ago, and it's actually helping potential loners find new friends. According to a 2013 report by the American Psychological Association, more than 70 percent of gamers play with at least one friend and millions of people have joined virtual worlds through social games like Farmville to MMORPGs like World of Warcraft. These types of games encourage cooperation and teamwork, and considering the typical World of Warcraft player logs more than 22 hours per week online, it stands to reason that most players would find camaraderie there. Along with virtual friends, video games are also popular among real-life pals to throw down online, keeping in touch (and smack-talking) with headsets.

They'll keep your mind more nimble

Puzzle games make you think, and research shows they can help keep your mind sharp if you play them consistently.

In 2013, The Huffington Post reported on a University of Iowa study of 681 healthy individuals, ages 50 and older. Some of the subjects frequently played a video game designed to improve mental processing, while the others did not. The results? The ones playing the video game were able to slow and delay the typical decline in cognitive speed and abilities by as much as six years. Put simply, playing the right types of video games can help keep your brain in shape.

Here's what one of the study's lead authors had to say about the findings: "We've shown that 10 hours is enough to slow the decline by several years. We saw a range across all our tests from a minimum of a year-and-a-half all the way up to about six-and-a-half years of recovery or improvement. From just 10 to 14 hours of training, that's quite a lot of improvement."

Even if you're not playing this specially designed game, pretty much any video game can help. Jason Allaire, an associate professor in the department of psychology at North Carolina State University in Raleigh, noted most games are complex enough that they'll push your brain and help stimulate those processing centers. So feel free to hook your grandpa up to World of Warcraft. He'll thank you.