1. It's actually a common disorder called "sleep apnea," and it affects about 5–10% of adults. Tap to play or pause GIF Tap to play or pause GIF Tap to play or pause GIF Tap to play or pause GIF FOX / Via says.com "The easiest way to define sleep apnea is you stop breathing for at least 10 seconds more than five times an hour during sleep, and this significantly impacts your overall health," Michael Breus, Ph.D., clinical psychologist and fellow of the American Academy of Sleep Medicine, told BuzzFeed Health. It affects over 18 million Americans, or roughly 5–10% of adults and 2–3% of children. Before we explain sleep apnea, let's quickly break down how breathing works. When you're awake, the muscles of your throat act to keep the airway straight and open so air can flow in and out of your lungs. When you sleep, these same muscles relax and your throat gets narrower. Normally, this doesn't close the airway, it just slows down breathing during sleep. However, during sleep apnea there's either a blockage of the airway or your brain stops telling your lungs to breathe. The result? Your throat muscles fail to keep the airway open so air can't flow in or out of the lungs and you stop breathing (apnea). 2. It usually happens when the airway becomes partially or fully blocked. Robroxton / Getty Images / Via thinkstockphotos.com This is the most common type, known as obstructive sleep apnea. "In this case, there's an actual blockage which causes the physical narrowing or closing of the throat," Breus says. If it's a partial blockage, it causes very shallow breaths, which is called "hypopnea." So despite your body's effort to breathe, oxygen can no longer get inside your body. This can happen because of an anatomical problem or because there's too much tissue in the throat and windpipe. Or it can just happen randomly. 3. Obstructive sleep apnea is usually caused by abnormal anatomy or excess weight around the neck. Chameleonseye / Getty Images / Via thinkstockphotos.com Abnormal anatomy can include very large tonsils or a large tongue that obstructs the airway, Breus says. It could also be excess tissue in the mouth or throat, the shape of your palate (roof of your mouth), or the bone structure of your head and neck. These anatomical differences make it harder for the throat muscles to keep the windpipe open, or they can create blockages when someone sleeps. Additionally, having a BMI over 30 can increase someone's risk of obstructive sleep apnea or the severity of the apnea, says Breus. According to the NIH, the primary reason is because extra soft tissue can thicken the walls of the windpipe, making it narrower and harder to keep open. Also, when you sleep the extra weight on the neck can get pushed down by gravity onto the throat, which forces it to close, Breus says. 4. That said, obesity doesn't necessarily cause sleep apnea, and literally anyone can have it. Tap to play or pause GIF Tap to play or pause GIF Tap to play or pause GIF Tap to play or pause GIF Cartoon Network / Via reactiongifs.com Having a BMI over 30 doesn't mean you'll definitely develop sleep apnea; it can just significantly increase your risk of getting it or worsen the severity of an anatomical problem. "People of all weights can get sleep apnea, even small children," Breus says. 5. The less common type is "central sleep apnea," where the brain just tells the lungs to stop moving. Tap to play or pause GIF Tap to play or pause GIF Tap to play or pause GIF Tap to play or pause GIF TedEd / Via teded.tumblr.com Central sleep apnea is much more rare and serious. "This is a problem with the central nervous system where the part of your brain that controls breathing just tells your lungs 'Hey, you don't need to breathe,'" says Breus. Central sleep apnea is much more difficult to treat, he says, because the root of the problem can be several things. Possible causes include brain tumors, chiari malformation (when part of the brain is formed outside the skull and pinches on the respiratory nerves), emphysema, or chronic obstructive pulmonary disease (COPD), Breus says. Old age can also make it harder for your brain to signal to the throat that it needs to stay stiff throughout the night. There's also a type called "mixed sleep apnea," which is a combination of the obstructive and central types. 6. So what happens when you stop breathing for a bit? Eventually your brain realizes there's a lack of oxygen in the body and wakes you up to breathe. Tap to play or pause GIF Tap to play or pause GIF Tap to play or pause GIF Tap to play or pause GIF Polygram Filmed Entertainment / Via gifemotions.tumblr.com Usually with a loud snorting, choking, or gasping sound. This pause in breathing followed by waking up to take a breath is called an "apneic event," says Breus. "After you pause breathing, your heart rate slows down in order to not blow through all the oxygen too quickly because now there's a limited amount in the body," says Breus. Then, the level of oxygen in the blood drops so once the blood circulates to the brain, the brain realizes the body is oxygen-deprived and speeds your heart rate back up so you can wake up and breathe again, Breus says. This whole ordeal is called an "apneic event." 7. These "apneic events" can happen anywhere from five times to over 30 times every hour. Tap to play or pause GIF Tap to play or pause GIF Tap to play or pause GIF Tap to play or pause GIF FX / Via rollergirlsarebatshitcrazy.tumblr.com "In order to meet the criteria of sleep apnea, the pauses in breathing have to happen at least five times in an hour for adults and at least once or more in an hour for children," Breus says. Sleep apnea ranges from mild to severe depending on the frequency of the pauses. "Five to 15 times in an hour is considered mild sleep apnea, 15 to 30 times is moderate, and 30 or above is severe," Breus says. "The worst I've seen was 200 times an hour, which was so frequent they barely slept for 10 seconds at a time before they stopped breathing," Breus says. That being said, sleep apnea this severe is not the norm. 8. Alcohol, sleeping pills, and muscle relaxants can all make sleep apnea worse. Giselleflissak / Getty Images / Via thinkstockphotos.com "Anything that can relax your muscles will make sleep apnea worse because it just helps the throat muscles collapse and close the airway," Breus says. This also includes some anti-anxiety medications like benzodiazepines and even some sleeping medications — which is a big issue."Someone who doesn't know their daytime exhaustion is from sleep apnea might take sleeping pills to get a better night of sleep and unknowingly make the apnea significantly worse, and create a vicious cycle," Breus says. Other things that can worsen apnea include asthma and smoking, which increases your risk of other respiratory disorders. 9. Obviously all this waking up to breathe prevents you from falling into deep, restorative sleep. Tap to play or pause GIF Tap to play or pause GIF Tap to play or pause GIF Tap to play or pause GIF Nike / Via oncristianoronaldo.tumblr.com "You move through sleep in a particular order of stages to complete the sleep cycle, like steps to a dance," says Breus. One 90-minute sleep cycle consists of five stages: stage one (light sleep), stage two (full sleep onset), stage three and four (deep sleep), and REM sleep (dream sleep).Apneic events really screw with that sleep cycle. "If every 10 minutes you stop breathing so your body wakes up to take a breath, this prevents you from following the path of sleep stages and you have to start over again from stage one each time," says Breus. As a result, people with sleep apnea never really enter stages three or four, or REM sleep, which are the deepest and most restorative stages. 10. So a major symptom of sleep apnea is severe exhaustion and fatigue during the day. Nickelodeon / Via spongegifs.tumblr.com If a person never fully enters the deep sleep stages, they will wake up the next day feeling physically and mentally exhausted, Breus says. Even if someone with sleep apnea sleeps for 12 hours, they might still feel very sleep-deprived the next day because their sleep was more of a superficial rest than a deep, restorative one. 11. Oh, also, you probably won't have any memory of your sleep apnea. Tap to play or pause GIF Tap to play or pause GIF Tap to play or pause GIF Tap to play or pause GIF HBO / Via fuckyeahreactions.tumblr.com Yes, despite how traumatic sleep apnea sounds, these quick gasps for air usually happen too fast for you to remember that they even happened. And when the body wakes up to breathe, only the body fully wakes up — not the brain. "You actually have to be awake for a full 30 seconds to consciously realize that you are awake, but the body falls right back into sleep immediately after it wakes up to take a breath," Breus says. So people who have sleep apnea often can't recall that they stopped breathing even if it's happening all night long. 12. So you probably won't know you have it until a sleeping partner points it out. Tap to play or pause GIF Tap to play or pause GIF Tap to play or pause GIF Tap to play or pause GIF FOX / Via imgur.com Remember that loud choking or coughing sound we mentioned? Well if someone is sharing the bed with you, they usually wake up from the noise. "They come in complaining that their partner was snoring like a freight train then stopped breathing and it sounded like they were dying — it's very alarming," Breus says. So it's often not the person with sleep apnea but whoever they sleep with who notices the problem.If you sleep alone, this can be a big problem, says Breus. "People get so frustrated because they're exhausted but they have no idea it's from sleep apnea and they'll try new mattresses or sleep meds but none of it works," says Breus. Other symptoms include tiredness, headaches, and trouble focusing after sleep — so if you have these you might want to bring it up with your doctor. 13. Untreated sleep apnea can have long-term health effects like high blood pressure, stroke, and weight gain. Alexraths / Getty Images / Via thinkstockphotos.com "The repeated slowing down and speeding up puts a big load on the heart, which can lead to refractory hypertension, a form of high blood pressure that you can't control with medication," Breus says. Likewise, the apneic episodes can increase your risk of stroke, arrhythmia (irregular heartbeat), heart failure, and even death. "If you already have a severe heart condition, sleep apnea could lead to a fatal heart attack during sleep," Breus says.Just as obesity can worsen sleep apnea, it can go the other way around. If a person suffers from sleep apnea, it can change the way their body uses energy. And the daytime exhaustion from apnea can make it difficult to exercise or eat healthily, creating an unhealthy lifestyle that leads to obesity. 14. In order to get diagnosed, you usually have to do a sleep study. Tap to play or pause GIF Tap to play or pause GIF Tap to play or pause GIF Tap to play or pause GIF Cartoon Network / Via lowkeloki.tumblr.com Sleep apnea is typically diagnosed by both recognizing the symptoms and examining the person's sleeping behavior in a sleep study. "Usually we'll look for symptoms such as being tired or irritable or waking up with headaches, then we'll send them to a sleep lab to see if it's from apnea," Breus says. What's involved in a sleep study? It's a non-invasive exam that requires you to sleep overnight (comfortably) at a lab so doctors can monitor your body and brain during sleep and pick up any issues. They use EEG monitors to track brain activity and also measure things like oxygen levels in the blood, heart rate, and snoring — so it's a very reliable test for sleep apnea. 15. The most common treatment is the CPAP machine, but some people opt for surgery or dental appliances. Brian Chase / Getty Images / Via thinkstockphotos.com The CPAP machine is basically a mask that blows air circulated from your room into your throat to keep the airway from closing. "It's the gold standard of treatment and works about 95% of the time... but the problem is only about 50% of people tolerate it," Breus says. Sure, wearing a big mask to sleep might sound annoying and uncomfortable but there's an adjustment period for everything, right? "Once people get used to the CPAP they can't sleep without it," Breus says.Other obstructive sleep apnea treatments include "mandibular advancement devices," says Breus. These are retainer-like appliances that move the bottom jaw slightly forward to keep the airway open all night. Surgery is another option, says Breus, but unless there's a clear obstruction to fix or remove, the effectiveness of surgery is limited. Weight loss may be a part of sleep apnea treatment, but it's generally not the only fix — as obesity is a risk factor, not a direct cause. "Treating the less common form, central sleep apnea, is very difficult because you essentially have to teach the brain how to breathe better," says Breus. So don't panic...but if you have any of the sleep apnea symptoms you might want to talk to your doctor or look into getting a sleep study! Tap to play or pause GIF Tap to play or pause GIF Tap to play or pause GIF Tap to play or pause GIF Cartoon Network / Via bustle.com Sleep apnea is a very common condition, so don't worry if you think you might have it. A sleep medicine doctor can help you explore your treatment options so you can get restful sleep again and have more energy during the day! For more information about sleep apnea, visit the National Sleep Foundation. Happy sleeping!