About 10%-15% of people experience chronic insomnia

A quick technical overview of insomnia

Insomnia is one of the world's most common sleep disorders. Characterized by difficulties falling and staying asleep, long-term struggles with insomnia can prelude or contribute to health difficulties. Treatments range from sleep hygiene management and relaxation therapy, and medication, including antidepressants and melatonin.

Clinical insomnia is defined as trouble sleeping for three nights per week for at least one month

The term "insomnia" is often used in popular culture to refer to general difficulty sleeping or staying asleep. In the US, insomnia transitions to a clinical disorder when symptoms—dissatisfying, nonrestful, and life-disrupting sleep—occur at least three nights per week for at least one month and cause "clinically significant" distress in important areas of life.

A framework for the various potential causes of insomnia

Insomnia typically occurs in people dealing with life stressors and physical or mental health conditions, though the exact cause continues to elude researchers. Generally, the factors can be broken down into external (such as stress, medication, etc.) or internal (neurological) factors.

The overlooked physical causes of insomnia

Persistent lack of sleep is dangerous for anyone, but women are especially unlikely to have their symptoms taken seriously. This article highlights the physical causes of insomnia—a condition often written off as solely psychological—and the importance of early diagnosis. The writer, Courtney Maum, was diagnosed with an anterior nasal valve collapse as the source of her insomnia.

What it's like to live with insomnia

The biological process Shakespeare referred to as the chief nourisher of life's feast is necessary for the body and mind to rest and repair from the activities of daily life. As sleep evades the exhausted, sufferers also lose emotional stability, mental clarity, social connections, and more while simultaneously gaining waves of interrupted biological processes that can lead to disease and death.

We dream for around two hours each night, on average, but the exact purposes of dreams remains under investigation.

The US loses roughly $400B a year in productivity due to sleep deprivation

For an article about a woman who built a business empire telling bedtime stories, the Hustle created this graphic showing the estimated GDP loss associated with chronic insomnia. The United States had a much more significant loss than other countries.

Genetics play a role in the reliability of the body's biological clocks

Growing evidence suggests genetics influence when, how long, and how well one sleeps, meaning insomnia may have a genetic component. While exact insomnia biomarkers have yet to be determined, some genes, including those related to psychiatric disorders, have been implicated.

Narcolepsy occurs when the brain loses its ability to control its sleep-wake cycle.

Sleep is often viewed individually, when its impact and meaning may be more communal

At any given point, roughly 2 billion people may be asleep on Earth. The typical scientific description of sleep focuses on its individual impact, but the phenomenon shapes whole cultures and eons. This essay prompts a fresh rethinking of the importance of sleep for humanity.

Roughly 1 in 5 people experience lucid dreaming at least once a month—that's the ability to control or influence your dream environment.

Forty to 110 minutes of deep sleep is recommended per night

Adults typically spend 10% to 20% of the night in deep sleep, also known as slow-wave sleep, with the rest of the night spent either in light sleep or REM states.

People with a sleep disorder called REM Sleep without Atonia don't experience the temporary paralysis of skeletal muscles that typically occurs during REM sleep—instead, they have vivid dreams that they act out during sleep.

An estimated 1 in 250 people—a small subset of the population—reports they've never remembered a single dream.

Obsessing over sleep metrics leads to worse sleep quality

Over one-third of Americans have used wearable technology to track their sleep, and the anxiety over having perfect sleep data, or orthosomnia, has made getting a good night's sleep more difficult. Experts agree that most devices cannot correctly assess sleep details, making the data unreliable.

Why do we sometimes jolt awake before falling asleep?

Around 70% of people are estimated to experience the sensation of falling and jerking awake right as they're about to drift to sleep. That mysterious phenomenon is called hypnic jerking. As common as it is, hypnotic jerking remains disconcerting and hard to explain. While we don't yet have clear answers, peruse this article in Popular Science for some possible explanations as to why this happens.

Alcohol use disorder is the most common addiction in the US

This comprehensive overview from the Addiction Center uses recent data from SAMHSA’s National Survey to examine the 10 most common substance dependencies in the United States. It ranks addictions from alcohol (affecting 28.3 million Americans) to barbiturates, while highlighting key trends, risks, and societal impacts.

Stress and anxiety may lead to similar symptoms, but stress is a response to external triggers, while anxiety is persistent, and its symptoms won't disappear once an immediate stressor is gone.

The REM cycle—named for the 'Rapid Eye Movement' that occurs during this stage of intense dreaming—happens around four to six times per night.

Tinnitus estimates vary, but may occur in 10%-15% of the population

This video discusses the mechanisms underlying tinnitus and explores the knowns and unknowns about the condition. Tinnitus most commonly occurs among those with hearing loss, suggesting that cochlear damage may be a factor.

Anxiety is one of the world's most common mental health disorders, causing persistent excessive fear and worry that interferes with daily activities.

The brain will attempt to rest itself in periods of chronic sleep deprivation

Skimping on sleep lengthens reaction times and blunts decision-making skills. At a certain point, the brain will try to sneak sleep where it can, shifting sections offline even as you remain awake. Going without sleep raises blood pressure, undermines the immune system, and increases one's risk of dementia.

1 in 10 US adults are taking medication for depression

A US government report indicates that about 10% of US adults took prescription medication for this disorder in 2023. Women, at 15.3%, were more than twice as likely to take one of these medications than the 7.4% of men.

A third of US couples have opted for a 'sleep divorce'

A 2023 survey of roughly 2,000 US adults showed roughly a third of the participants opted to stay in a different room from their partner at night. Reasons for the so-called "sleep divorce" varied, from snoring issues to offset schedules. The survey, run by the American Academy for Sleep Medicine, also revealed the most sleep divorces within millennials. See the study for more on this change in sleep habits.

Temperature and certain medications can also affect your circadian rhythms

Although light and dark have the largest influence on circadian rhythms, temperature, stress, and certain medications are among the factors that also play a role. Persistent trouble sleeping or staying asleep may signal it’s time to see your doctor to get a better sleep-wake schedule.

Humans may have evolved to need less sleep.

Testing five common beliefs about bedbugs

Bedbugs are one of the most stigmatized pest infestations due to their resilience and tendency to dwell where humans are most unconscious for long periods of time: beds. A bedbug problem can lead to horror stories and intensive interventions to...

Understanding the stages of sleep

Do you have trouble keeping the different stages of sleep straight and organized in your mind? Us too. Sometimes it helps to have a straightforward listing of what each stage is and why it’s important. Look no further than this resource from Lumen. It is a basic outline of the four stages of the sleep cycle, along with the brainwaves and attributes that characterize each. If you’re brave enough, test yourself on the built-in quiz!

The lost medieval habit of 'two sleeps'

While most people accept a single seven-to-nine-hour nightly slumber is ideal, the approach is a relatively modern idea. For centuries, interrupted sleep was the norm, with historians uncovering descriptions of two periods of sleep during the normal 24-hour cycle.

What happens when we sleep

Sleep is a highly specialized and complex process that begins via signals from a region of the brain called the hypothalamus. As explained in this overview video from The Economist, the hypothalamus maintains our circadian rhythm by using light cues from our environment to regulate sleep via a compound known as melatonin. Once asleep, the brain begins the "sleep cycle" and progresses through the four stages of sleep over and over again each night.

Circadian rhythm disruption can influence various mental health disorders

This 2020 research overview surveys the relationship between disrupted circadian clocks and disorders including schizophrenia, anxiety, and bipolar disorder. It incorporates findings and therapeutic approaches drawing from human night shift studies and jet lag studies alongside animal research.

What sleep is for and why you can’t live without it

Sleep is one of the most important needs that humans have. The body uses sleep as a time of restoration and rejuvenation, as body tissues repair themselves, growth hormones are released, and the process continues. Brain plasticity theorists believe that sleep is also used for the processing and consolidating of new memories.

High-quality sleep is effectively a superpower

Sleep is critical to maintaining healthy biological functions. From restoring energy to consolidating memories, aiding immune system functions and balancing hormone production, optimizing sleep habits are one of the most important ingredients to healthy living.

The evidence for the best sleep positions

For a behavior so crucial to human health, sleep positions are reportedly understudied by researchers. This article summarizes some of the more recent studies, taking into account the various forms of problems encountered during sleep: neck and back pain, snoring, acid reflux, and facial skin damage. Most studies point to side-sleeping as the most optimal, with sleeping on one's front as the least helpful. Read the piece to see which position is best for you.

Type 2 diabetes is a chronic disease that develops over time

Almost 90 to 95% of people with diabetes have Type 2 diabetes, occuring when the pancreas doesn't make enough insulin or the insulin fails to work correctly. Insulin malfunction causes the pancreas to crank out increasingly high amounts of the blood sugar-regulating hormone, leading to overwork and reductions in production.

Emerging research suggests that cannabis, used by about 9% of American adults as a sleep aid, may suppress rapid eye movement and lead to worse quality sleep and fewer remembered dreams.

Why don’t you remember all your dreams?

Despite being a near-nightly occurrence, we remember very few of our dreams. Researchers believe reduced activity in regions where memories are stored, a different neurochemical environment during sleep, and rapid transition during waking contribute to this phenomenon.

Sleep apnea explained

While sleep apnea is directly tied to an increased risk of cardiovascular and metabolic health problems, many affected people are unaware of their problem. Sleep apnea occurs when upper airway muscles relax during sleep and pinch off the airway, which can cause breathing to pause for 10 seconds or more at a time. Sleep partners (rather than those inflicted) are often the first to notice breathing pauses or loud snoring in their bedmates.

Are you hypnotizable?

What causes some people to genuinely fall under the spell of hypnosis and others not? The technique only appears to work easily on about 10% of people, and a variety of both genetic and psychological factors determines one's susceptibility. Researchers suggest effective hypnosis has more to do with a person's self-control than with external influence—and the technique can have tangible benefits.

Diabetes is a chronic disease linked to insulin production and high blood sugar

Diabetes is a chronic, progressive disease caused by a lack of, or problems processing, the hormone insulin, leading to persistently high blood sugar. Around 90 to 95% of cases are Type 2 (chronic and caused by factors like diet and environment). The remainder are Type 1 diabetes (an autoimmune disorder).

Five patterns may define how we sleep—not just night owl or early bird.

Sleepwalking, or somnambulism, is a bit of a misnomer since many things can occur during this state, including speaking, using the bathroom, and more.

Bipolar disorder, which is characterized by extreme mood swings, affects nearly 3% of the US population

There are two types of this disorder. Bipolar 1 features a significant manic episode—abnormally elevated mood and frantic energy—followed by repeated depression, while Bipolar 2 vacillates between depressive episodes and hypomania, a milder form of mania, but not a full mania. Listen to this podcast as experts explain the condition.

One person dies from opioids every 7 to 8 minutes

This collection of infographics by the National Institute for Health Care Management helps put the crisis into perspective. The opioid epidemic has had three waves. Opioid-related deaths increasingly involve synthetic versions of the drug class, contributing to 83 percent of all opioid-related deaths in 2020. Use these infographics to learn more about the crisis.

1 in 5 American adults report daily loneliness

Twenty percent of US adults said they felt lonely "a lot of the day yesterday" in Gallup polling conducted in 2024. The survey was conducted with more than 6,000 adults who took part in a web survey.

The most common birthdays

Nine of the top 10 most common birthdays fall in September, with Sept. 9 being the most common. However, August is the most common birth month, followed by July and December. On the flip side, the least common birthdays are around major holidays, with Christmas Day being the rarest—probably due to doctors scheduling fewer inductions and C-sections on those days. Find out more birthday surprises here.

See how anxiety disorder rates vary across 200+ countries, with Portugal, Malta, Brazil, and Iran reporting the highest burdens.

The body's sleep-wake cycle is one of its many circadian rhythms

The body's sleep-wake cycle is one of its many circadian rhythms, which are behaviors or biological processes that exhibit 24-hour patterns. These rhythms are deeply impacted by light exposure, food availability, and much more, meaning where you live impacts your sleep.

Do sleep-tracking apps work?

Can technology help us sleep better? As wearables and apps promise to optimize our nights, this New York Times investigation reveals some troubling findings after columnist Brian Chen used a wearable for two weeks to track his sleep. He discovered that sleep trackers not only provide frequently questionable data but can also paradoxically worsen sleep problems by causing users to obsess over their metrics — a new condition researchers are calling ‘orthosomnia.’

Sleep disorders can exacerbate neurological and other health conditions

Brain regions that control sleep sit adjacent to those that regulate the autonomic nervous system, which controls involuntary bodily functions like heart and breathing rates. These neighbors influence each other, meaning poor sleep can impair or negatively impact the ANS, further disturbing sleep.