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Family Health

Yale Medicine Sleep Content Center

March 14, 2023


Sleep is essential to maintaining good health. And yet, up to 70 million adults in the United States report having a chronic sleep disorder, and many others struggle with sleep-related issues. Failing to pay attention to—and even get help for—your sleep problems can lead to a variety of physical, mental, and emotional health problems.

The good news is that most sleep disorders respond well to treatment.

Our goal for this page is to provide a resource where you can get answers to your sleep-related questions and also connect to other information related to sleep.

Understanding sleep and circadian systems

Circadian systems, or rhythms, may sound complex, but it really is all about gaining an understanding of how your own body works so that you maximize the odds that you will be able to get a good night’s sleep naturally.

Simply put, circadian rhythms are the physical, mental, and behavioral changes that happen in your body every 24 hours. Getting a handle on how they function can help you get the rest you need, which is necessary for your physical, mental, and emotional health.

Watch this video in which Dr. Knauert discusses circadian systems and how you can play around with yours to get optimal rest.

The connection between sleep, diabetes, and obesity

It’s obvious that sleep is important to everyday health, but did you know that it also plays an important role in managing weight?

“When it comes to diabetes and obesity, poor sleep is often a factor,” says Brian Wojeck, MD, MPH, a Yale Medicine endocrinologist.

That’s because sleep deprivation can create an imbalance in the hormones that regulate your appetite—ghrelin and leptin. Leptin helps you feel full; ghrelin makes you feel hungry. Leptin levels typically rise during sleep, so if you aren’t getting enough sleep, your leptin levels decrease, so you feel hungrier and are, therefore, likelier to eat excessively and gain weight. Likewise, sleep disruptions of any kind can cause an increase in ghrelin, Dr. Wojeck says.

“As a result, people who are more sleep-deprived tend to gain weight for those physiologic reasons,” Dr. Wojeck says, adding that diabetes can then be a result of both the increase of blood sugar and ghrelin.

Watch this video in which Dr. Wojeck discusses how weight and sleep are related.

How aging affects sleep

Though it is often said that people need less sleep as they age, the current recommended sleep guidelines for all adult age groups are almost identical. According to the National Sleep Foundation, people between 18 and 64 should aim for seven or more hours of sleep a night; people 65 and older should get seven to eight hours each night.

Still, the sleep patterns of older people are impacted by multiple factors, from medical conditions to medications says Brienne Miner, MD, MHS, a Yale Medicine geriatric and sleep medicine specialist.

“Medical conditions can cause pain or other sleep-disruptive symptoms, or people can be on medications that could make them very sleepy during the day and make it hard for them to sleep at night,” Dr. Miner says. “Or, interestingly, those medications might cause or worsen an underlying sleep disorder.”

Many things can contribute to sleep problems as people age, explains Dr. Miner. “The good news is that there are many treatment options that don’t involve taking yet another medication.”

Watch this video in which Dr. Miner discusses how sleep changes as we age.

The health effects of poor sleep

Sleep is linked to nearly every bodily function—from how well our bodies fight infection to how well we think, so getting a good rest every night is important.

Lack of sleep also affects our emotions—making us not only tired but also more irritable—two things that, over time, can lead to depression and anxiety, Dr. Zinchuk adds.

If you are sleep-deprived, the good news is that there are several strategies you can use to help you get through the day and back on track.

Watch this video in which Dr. Zinchuk talks more about the effects of sleep deprivation.

How sleep affects your immune system

It’s a universal experience: you start to feel sick, and all you want to do is sleep. And yet, rest does not come.

“That’s because when your immune system is fighting off a pathogen, your sleep quality is often not very good,” says Yvonne Chu, MD, a sleep medicine specialist at the VA Connecticut Healthcare System.

Sleep study results show that when someone has an acute illness, there’s a decrease in rapid eye movement, or REM, sleep. REM sleep is believed to be the most restorative stage of sleep, Dr. Chu explains.

What’s more, poor sleep can also increase your susceptibility to certain types of illness. “Studies have shown that those who chronically get less than seven hours of sleep a night are three times as likely to develop the common cold compared to those who routinely get eight hours or more of sleep,” Dr. Chu says.

The bottom line, Dr. Chu says, is that there is no substitute for getting consistent, good quality sleep, especially if we want to reap the immune system benefits sleep can offer.

Watch this video in which Dr. Chu talks more about sleep and your immune system.

How to manage insomnia

It’s a rare person who has not experienced at least an occasional night or two of tossing and turning in bed, feeling restless and having difficulty falling or asleep. But these once-in-a-while episodes of sleeplessness are not the same as having insomnia. The distinction is that insomnia involves persistent and consistent sleep difficulties, as well as a significant decline in performance and functioning during the day, explains Susan Rubman, PhD, a clinical psychologist in sleep medicine.

Part of the problem with insomnia is that you can become accustomed to restless sleep patterns. “That restlessness when trying to sleep is what our brains then learn,” Rubman says. “Through repeated pairings of being in bed and tossing and turning, we create a learned habit of arousal and awakening that, like any other habit, becomes persistent over time.”

Ultimately, it’s important for people to know that it’s normal to have trouble sleeping, especially during times of stress. But if it becomes a persistent pattern, contact your primary care provider or a sleep disorder center for help.

Watch this video in which Rubman talks more about insomnia.

How to get better sleep

Sleep is essential. Quality rest is necessary for maintaining good physical and mental health throughout your life. How you feel when you’re awake is partly determined by what happens during sleep; the body is actively engaged in restorative processes during this time.

Getting great sleep boils down to two central requirements: having a consistent sleep schedule and turning off your “busy brain,” says Lynelle Schneeberg, PsyD, a Yale Medicine sleep psychologist.

“Interestingly, waking up at the same time every day is more important than having a consistent bedtime,” Schneeberg says. “That’s because your body pays attention to what time you get out of bed in the morning and starts a ‘countdown clock’ to when your bedtime should be.” It’s also helpful that controlling what time you wake up is much easier than controlling what time you fall asleep, she adds.

On the nights you don’t fall right back to sleep and start worrying about things you have to do the next day, pick up your book or eReader to distract yourself until you feel drowsy again, she advises.

Schneeberg shares more advice on getting a good night’s sleep in this video.

What is snoring?

Snoring is harsh, noisy, rattling breathing that is caused by an improper inflow and outflow of air while you’re sleeping. When you fall asleep, your throat muscles naturally relax, your tongue slips backward, and your throat narrows. If there is anything obstructing the free flow of air at the back of your mouth and nose—a sinus infection, a nasal polyp, tonsillitis—it can exacerbate the narrowing of your airway. That leads to vibrations in the loose throat muscles, causing the snoring sound.

As many as 90 million Americans report snoring at one time or another, while 37 million say they snore regularly. Sometimes their snoring really is harmless. But it’s a problem if it makes you wake up throughout the night and, as a result, you feel tired all day. In the worst cases, snoring can signal a serious condition such as obstructive sleep apnea, a common condition is linked to cardiac problems and can be fatal if left untreated.

In this article, Yale Medicine experts discuss what you need to know about snoring.

What is sleep apnea?

Sleep apnea is a condition that causes people to stop breathing periodically while they’re asleep. The number of those interruptions can range widely, varying from about five times an hour to as many as 100 or more times an hour. Each interruption typically lasts from 10 to 20 seconds.

Whenever a person stops breathing, even momentarily, the brain is awakened slightly, preventing the deepest, most restful sleep. As a result, people with sleep apnea get much lower quality sleep, and often wake up feeling very tired, despite seemingly getting a full night’s rest.

In this article, Yale Medicine experts discuss the symptoms of and treatments for sleep apnea.

Sleep apnea and CPAP: What to know

High on the list of sounds no one wants to hear is the snoring of a bed partner. But sometimes that harsh, rasping sound is more than just annoying; it can be life-threatening. About half of the 90 million Americans who snore have obstructive sleep apnea (OSA), a condition that actually disrupts breathing, is linked to heart disease, and can even be fatal. Even more troubling, it’s possible to have the condition and not even know it.

Perhaps unsurprisingly, many people avoid seeking help for snoring because they don’t think it’s a big deal. Or they do, but don’t want to undergo a sleep test in an overnight lab (which is how OSA is typically diagnosed). Or they’re worried they’ll be diagnosed with OSA and have to use the most common—and notoriously difficult to tolerate—treatment: a continuous positive air pressure machine, or a CPAP.

And since one company recently recalled some of its CPAP devices, there is growing confusion among many with OSA about whether or not they should even use a CPAP at all.

To help clear up the confusion, we spoke with Henry Yaggi, MD, MPH, a pulmonologist and director of the Yale Center for Sleep Medicine, and Andrey Zinchuk, MD, MHS, who directs an Advanced Apnea Management Program at Yale.

Read the article: Seven things you need to know about obstructive sleep apnea, advances in CPAPs, and other OSA treatments.

Kids and poor sleep: A habit that’s breakable

Children enter the world hardwired with plenty of quirks and traits, but no one is born a “bad sleeper.” In fact, sleep troubles are a habit kids pick up—and one that parents often unknowingly reinforce.

Though it’s not easy to change poor sleep habits, it’s not impossible—particularly for children in preschool and elementary school, says Lynelle Schneeberg, PsyD, a Yale Medicine psychologist and author of “Become Your Child’s Sleep Coach: The Bedtime Doctor’s 5-Step Guide, Ages 3-10” (Lifelong Books).

It’s with the best of intentions that parents end up reinforcing poor sleep habits, notes Schneeberg, identifying “too much parental assistance” as a key factor fueling the problem. “It is challenging to help children in this age group learn to fall asleep independently at bedtime because they can talk and walk, which means they can ask you to come back to their room for many creative reasons, or come out of their rooms to find you and ask for one more escorted trip to the bathroom, more ice for their water cup, and so on,” Schneeberg explains. “Luckily, their brains are adaptable, and they can learn new ways to fall asleep that don’t involve a parent.”

Understanding how you respond to your child’s nighttime requests is the first step to addressing them, says Craig Canapari, MD, a Yale Medicine pediatric sleep specialist, pulmonologist, and author of “It’s Never Too Late to Sleep Train: The Low-Stress Way to High-Quality Sleep for Babies, Kids, and Parents” (Rodale).

So what’s the solution? Create new, healthy habits around everything involving your child’s sleep routine. “Routine” is the key word here. Children naturally crave consistency and predictability—not just for sleep, but for most aspects of their day-to-day lives. Clear rules and expectations help reduce anxiety because your child knows what to expect, and therefore can help things run smoothly. A firm order of events around bedtime will allow you and your child to adopt good habits—meaning you can turn on “autopilot” and follow a set plan.

In their books, Schneeberg and Dr. Canapari both delve into the nitty-gritty of how to create a solid bedtime routine, offering ways to tackle common problems, including night terrors, early wakings, and children who won’t sleep in their own beds.

But before you can bring about positive change, it helps to understand where things went wrong.

In this article, we highlight a few mistakes caregivers make and offer tips from Dr. Canapari and Schneeberg on how to fix them. 

How a pediatric sleep specialist brought one family some peace

Frustrated, helpless—and utterly exhausted. That’s how my husband and I felt last August when we arrived at the offices of a Yale Medicine pediatric sleep specialist with our nearly 4-year-old son, Zachary, in tow.

Like most parents, we understood that uninterrupted sleep was something we might not enjoy until our kids went to college—if ever. But our situation with Zach had become untenable. He woke up multiple times each night and wouldn’t go back to sleep unless we lay beside him.

When he was a baby, the situation was even worse. The only way I could get him to sleep was to lie next to him on our bed at 7 p.m., with my nose practically touching his.

But now that he was older, more mobile and able to express his fears, standard baby sleep-training methods were no help. Desperate for a solution, I read scores of books, beseeched our pediatrician for suggestions and talked to other parents. None of the advice worked.

Since I had just started working at Yale School of Medicine, I knew there were resources at the ready. We made an appointment with Yale Medicine’s Craig A. Canapari, MD, director of the pediatric Sleep Medicine Program. The program treats a variety of respiratory and nonrespiratory sleep disorders from insomnia and restless legs syndrome to obstructive sleep apnea and complications from neuromuscular diseases. Dr. Canapari helped us figure our way out of this situation.

Read the article about how a Yale Medicine sleep expert brought peace to one family.

What is a pediatric sleep study?

A sleepless child means your house also has at least one sleepless parent—and maybe suffering siblings as well. If your child struggles with sleep, snores, exhibits symptoms of excessive daytime drowsiness—or, conversely, is hyperactive during the day—he or she might benefit from an overnight sleep study.

In this article, Yale Medicine experts discuss what a sleep study entails for a child.

What is pediatric obstructive sleep apnea?

If your child snores, sleeps with his or her mouth open, has a poor attention span and/or behavioral issues, obstructive sleep apnea may be the problem.

Most children don’t snore, so if your child does, consider asking your doctor whether there might be a problem. At least 2 to 3% of children are believed to have sleep apnea, with the disorder believed to be as high as 10 to 20% in children who habitually snore.

Sleep apnea is a condition in which the muscles at the back of the throat intermittently relax too much, partially or completely blocking the airway. This means the child’s breathing may be starting and stopping during sleep. These breathing interruptions, which typically last 10 to 20 seconds, may happen anywhere from five to more than 30 times in one hour.

Every time your child stops breathing, even briefly, the brain awakens slightly. Consequently, their quality of sleep is extremely poor, which can make your child tired and cranky during the day. This can lead to other health problems, including poor growth.

Fortunately, pediatric obstructive sleep apnea, or OSA, is treatable. If the problem is the result of enlarged tonsils or adenoids, a simple surgery to remove either or both provides a cure. Other times, your child may need to wear a specialized medical device while they sleep.

In this article, Yale Medicine experts discuss the symptoms of and treatments for pediatric obstructive sleep apnea.