Obstructive sleep apnoea syndrome is a condition where your breathing repeatedly stops during sleep because your airway becomes blocked. This disrupts your rest and can affect your health in serious ways, but understanding the condition and exploring treatment options can help you breathe easier at night and feel more energetic during the day.

Understanding How Common This Condition Is

Obstructive sleep apnoea is far more widespread than many people realize. Research suggests that this condition affects up to one billion people around the world who are between the ages of 30 and 69.^[2] This makes it one of the most common sleep-related breathing disorders that healthcare providers encounter. The condition appears to be becoming even more prevalent, partly because rates of obesity are increasing, and excess body weight is one of the key factors that can contribute to airway blockage during sleep.^[6]

When we look at who is most affected, the pattern shows some clear differences. Studies estimate that among middle-aged adults in America, about 14% of men and 5% of women have obstructive sleep apnoea that causes noticeable daytime sleepiness.^[10] Men are more likely to receive a diagnosis before they reach age 50, while women’s risk increases after menopause.^[5] The condition doesn’t just affect adults though—children can also develop obstructive sleep apnoea, often due to enlarged tonsils or adenoids.^[5]

What Causes Your Airway to Close During Sleep

The root cause of obstructive sleep apnoea involves the muscles and soft tissues in your throat. When you’re awake, these muscles keep your airway open so air can flow freely into your lungs. But during sleep, all your muscles naturally relax to some degree—including those in your throat. In people with obstructive sleep apnoea, this relaxation goes too far. The muscles that support the soft tissues in your throat, including your tongue and the soft palate at the back of your throat, relax so much that these tissues can press against your windpipe.^[1]

When this happens, your airway narrows or closes completely, and breathing is momentarily cut off. This is what doctors call an apnoea—a pause in breathing that lasts at least 10 seconds.^[3] These pauses prevent oxygen from reaching your body, which triggers a survival reflex in your brain. Your brain wakes you up just enough to resume breathing, often with a snort or gasp. While this reflex keeps you alive, it also disrupts your sleep cycle, preventing you from getting the deep, restorative rest your body needs.^[2]

The process that leads to airway collapse during sleep is actually quite complex. It’s influenced by several factors working together. When you sleep, there’s a natural reduction in the signals your brain sends to control breathing. Combined with the relaxation of muscles and certain anatomical features of your throat and airway, this creates the perfect conditions for obstruction.^[3]

Who Is Most at Risk

While obstructive sleep apnoea can affect anyone regardless of age or body size, certain factors significantly increase your risk. Carrying excess body weight, particularly around your neck, is one of the strongest risk factors. When you have extra fat tissue in this area, it can physically press on your airway from the outside, making it more likely to collapse during sleep. About half of people with sleep apnoea are overweight.^[1] However, it’s important to understand that people at a healthy weight can also develop this condition, so body weight alone doesn’t tell the whole story.^[2]

The structure and shape of your head, neck, and throat also play a significant role. Having a naturally narrow airway, a thick neck, a large tongue, or enlarged tonsils and adenoids can all increase your risk. A large neck circumference is a particularly strong indicator—for men, this means a neck measuring more than 43 centimeters (17 inches), and for women, more than 37 centimeters (15 inches).^[2] Some people are born with an underbite, a small lower jaw, or other structural features that make their airway more prone to obstruction.^[2]

Your family history matters too. If close relatives have obstructive sleep apnoea, your risk is higher, suggesting that genetics play a role in who develops this condition.^[5] Certain genetic conditions that affect how the head and neck develop, such as Down syndrome or Prader-Willi syndrome, also increase the likelihood of sleep apnoea.^[2]

Age is another factor—your risk increases as you get older, though the condition can certainly affect younger people too.^[2] Lifestyle choices and habits also matter. Drinking alcohol relaxes the muscles in your throat excessively, making airway obstruction more likely during sleep. Smoking causes inflammation and increases mucus production in your airways, which can narrow them.^[5] Both of these habits can worsen symptoms or increase your risk of developing the condition in the first place.

Recognizing the Symptoms

The symptoms of obstructive sleep apnoea occur both during the night and throughout the day. Often, symptoms begin gradually and may be present for years before someone seeks medical help. Because you’re asleep when many of the most obvious signs occur, you might not be aware of them yourself. This is why the observations of a sleeping partner can be so valuable.^[4]

During the night, the most characteristic symptom is loud snoring. This snoring is typically habitual and loud enough to bother others sleeping nearby. But snoring alone doesn’t mean you have sleep apnoea—not everyone who snores has this condition, and not everyone with sleep apnoea snores loudly.^[1] What’s more telling is when the snoring is interrupted by pauses in breathing. A sleeping partner might notice that you stop breathing for brief periods, and these pauses often end with a snort, gasp, or choking sound as you struggle to take in air.^[1]

You might wake up during the night feeling short of breath or like you’re choking, though you may not remember these episodes in the morning. Many people with sleep apnoea experience frequent wakeups throughout the night and may toss and turn, feeling restless without understanding why.^[1] Night sweats are another common symptom, as are needing to urinate frequently during the night.^[1]

The daytime symptoms of obstructive sleep apnoea can significantly affect your quality of life. Because your sleep is constantly interrupted, you don’t get the deep, restorative rest your body needs. This leads to excessive daytime sleepiness or fatigue—many people describe it as waking up feeling as tired as when they went to bed, a feeling called nonrestorative sleep.^[4] At first, this sleepiness might only be noticeable during quiet activities like reading or watching television. But as the condition worsens, you may feel drowsy even during activities that normally require alertness, such as working, attending school, or driving. This can be dangerous, particularly when operating vehicles or machinery.^[4]

Morning headaches are common, along with having a dry or sore throat when you wake up. Many people experience problems with memory, concentration, and thinking clearly—tasks that require sustained attention become more difficult. Mood changes are also frequent, including feelings of depression, anxiety, or irritability. Sexual problems, including loss of interest in sex and impotence, can occur as well.^[1]

How to Prevent or Reduce Your Risk

While you can’t change certain risk factors like your age, genetics, or the basic structure of your airway, there are several lifestyle changes and preventive measures that can reduce your risk of developing obstructive sleep apnoea or help manage symptoms if you already have the condition.

Maintaining a healthy weight is one of the most effective preventive measures. Even a modest weight loss—around 10% of your body weight—can lead to a significant reduction in the severity of sleep apnoea, with some studies showing improvements of 20% to 30%.^[21] If you’re carrying excess weight, particularly around your neck and upper body, losing some of it can reduce the amount of tissue pressing on your airway during sleep.

Regular physical activity helps in multiple ways. Exercise can aid in weight management, strengthen the muscles that support your airway, and improve your overall sleep quality. Activities like yoga and breathing exercises can enhance lung capacity and oxygen flow, potentially reducing apnoea episodes.^[5] Aim for at least 30 minutes of moderate exercise most days of the week, though you should consult your doctor before starting any new exercise program, especially if you have other health concerns.^[19]

Limiting or avoiding alcohol, especially in the hours before bedtime, is important because alcohol relaxes throat muscles excessively. This makes your airway more likely to collapse during sleep.^[5] Similarly, avoiding sedatives and sleeping pills is wise, as these medications can have the same effect of over-relaxing the throat muscles.^[19]

If you smoke, quitting can make a real difference. Smoking increases inflammation and mucus production in your airways, which narrows them and makes obstruction more likely.^[5] Treating nasal allergies is also helpful, as allergies cause the tissues in your airways to swell, making it harder to breathe.^[21]

Your sleep position matters too. Sleeping on your side rather than on your back can help keep your airway open. When you sleep on your back, gravity pulls your tongue and soft tissues backward, increasing the chance of airway obstruction. Some people find it helpful to prop a body pillow against their back or even sew a tennis ball into the back of their pajamas to prevent rolling onto their back during the night.^[5]

Creating good sleep habits, called sleep hygiene, can improve your overall sleep quality. This includes going to bed and waking up at the same time every day, even on weekends, which helps regulate your body’s internal clock. Keeping your bedroom cool, dark, and quiet promotes better sleep. Avoiding heavy meals close to bedtime and limiting caffeine can also help.^[19]

What Happens in Your Body

Understanding what physically happens in your body when you have obstructive sleep apnoea helps explain why this condition can be so serious. The fundamental problem is mechanical—during sleep, when your throat muscles relax too much, the soft tissues in your throat collapse inward. This physically blocks your windpipe, preventing air from flowing into your lungs.^[2]

When air can’t get through, your blood oxygen levels begin to drop. At the same time, carbon dioxide builds up in your bloodstream because you can’t exhale it. Your body recognizes this as a life-threatening emergency. In response, your brain triggers a survival reflex that briefly wakes you up—just enough to tighten your throat muscles and gasp for air. This process happens automatically, and you often won’t remember these micro-awakenings in the morning, even though they may occur dozens or even hundreds of times throughout the night.^[2]

Each time this cycle repeats, it prevents you from entering or maintaining the deeper stages of sleep that your body needs for physical and mental restoration. The constant interruptions fragment your sleep into lighter stages. This is why people with untreated sleep apnoea often feel exhausted despite spending what seems like enough time in bed—their sleep simply isn’t restorative.^[3]

The repeated drops in oxygen levels and the struggle to restart breathing create stress throughout your body. Your heart rate and blood pressure fluctuate dramatically with each episode. The pressure inside your chest changes in exaggerated ways as you try to breathe against a closed airway. Over time, these acute effects during sleep can lead to more permanent changes in your cardiovascular system.^[10]

The lack of oxygen can damage your organs and blood vessels. Your heart has to work harder to pump blood through a body that isn’t getting enough oxygen. This strain, combined with the interrupted sleep, affects your body’s ability to regulate blood pressure, blood sugar, and other important functions. Inflammation increases throughout your body, and your metabolism can become disrupted.^[20]