What Causes Early Morning Awakenings?

By Brandon Peters, MD

There is something disappointing about waking up earlier than is necessary. It may be nice to doze in and out of sleep in the early morning hours, but it is especially upsetting if you cannot fall back asleep. What might cause someone to wake up before the alarm clock goes off? There are specific conditions, including a fair number of sleep and mood disorders, which might cause early morning awakenings.  By understanding these potential causes, you may be able to find a treatment that will keep you asleep until your desired wake time.

The Role of Insomnia

The most important cause of difficulty staying asleep near morning is insomnia. Insomnia is defined as difficulty falling or staying asleep or sleep that is simply not refreshing. These awakenings may occur throughout the night, but they tend to be more frequent in the second half of the night. This is due to a diminishing ability to sleep toward the morning hours.

The ability to sleep is linked to two processes, one called the homeostatic sleep drive and the other being the circadian rhythm (which will be discussed more later). The homeostatic sleep drive is the gradual desire for sleep that builds the longer a person stays awake. It relates to the gradual accumulation of a chemical within the brain called adenosine. This “sleepiness signal” eventually helps to initiate sleep. During sleep, it is cleared away, so that midway through the night, the desire for sleep is depleted. By morning, it should be completely gone.

If a person awakes in the night, especially if this awakening occurs toward morning, the ability to return to sleep will be compromised due to the lower levels of adenosine. Sleep may be greatly delayed, fragmented, or disrupted in insomnia, but awakenings near morning can be especially troublesome.

Anxiety and Depression May Provoke Awakenings

Any of the mood disorders, most notably anxiety and depression, can provoke awakenings. These typically occur in the several hours before the intended awakening. For example, if the alarm is set for 6 AM, someone with depression may start waking at 4 AM for no good reason. How can this be addressed?

As with insomnia, it is important to address the underlying contributing factors that lead to these awakenings. In the setting of psychiatric distress, these problems can persist. It is therefore necessary to treat any coexisting depression or anxiety. This may require the use of medications or counseling with the assistance of a psychologist or psychiatrist. Studies have shown that both, used in combination, are the most effective. Insomnia is especially well-treated with cognitive behavioral therapy for insomnia (CBTi).

It is clear that sleep can undermine mood. Conversely, mood problems can greatly affect sleep. By working on both issues together, the complexity of this relationship can be unraveled.

The Unexpected Influence of Sleep Apnea

It may seem peculiar to imagine that a breathing disorder such as obstructive sleep apnea may contribute to early morning awakenings. To better understand this relationship, it is necessary to carefully consider the structure of sleep.

It is artificial (but useful) to divide the night in half when considering the stages of sleep. In the first half of the night, slow-wave sleep more frequently occurs, especially among young people. In the second half, rapid eye movement (REM) sleep makes a more frequent appearance. Though the cycles of sleep occur regularly through the night, REM sleep becomes more prolonged towards morning. Therefore, we are more likely to awaken from it near morning and recall the vivid dreams that are associated with the state.

Sleep apnea is also more likely to occur during REM sleep. The muscles of the body are actively paralyzed during this stage, so that we are unable to act our dreams out. (If this does not occur, a condition called REM behavior disorder may result.) Muscles lining the upper airway are also paralyzed. This makes the airway more collapsible and when collapse occurs, it manifests as disrupted breathing and sleep apnea. Sleep apnea is often worsened during REM for this reason.

Therefore, morning awakenings may occur in the setting of sleep apnea that is worsened during the periods of REM that become more frequent and prolonged towards morning.

Morning Larks, Circadian Rhythms, and How Sleep Changes in Aging

The last major contributor to early morning awakenings is the class of conditions that are collectively known as circadian rhythm disorders. These include the natural tendency to wake early in the morning (so-called early birds or morning larks), advanced sleep phase syndrome, and natural changes that occur in sleep ability as we get older.

There are some who are just naturally morning people. They may prefer to fall asleep earlier (such as at 9 PM) and wake earlier (by 5 or 6 AM). This may be a lifelong preference. It isn’t necessarily abnormal, but it may lead to morning awakenings. If a sufficient amount of sleep is obtained before getting up for the day, then there is no reason to give it a second thought.

As we get older, our ability to maintain a continuous, uninterrupted period of sleep diminishes. The “machinery” of sleep (whatever we might conceive this to be) isn’t working as well as it used to. Sleep may become more fragmented. There may be more time spent awake in the transition to falling asleep and during the night. Slow-wave sleep diminishes. The total sleep time may be reduced. As part of this, early morning awakenings may occur.

In some cases, a condition called advanced sleep phase syndrome may become apparent. In this circadian rhythm disorder, the onset and offset of sleep moves forward by several hours. If it is disruptive to social life, it may be treated with the use of properly timed melatonin and light exposure at night.

If you suffer from morning awakenings, you should reflect on your situation and consider what might be contributing to the occurrence. If there is evidence for mood disorders, these should be addressed by a doctor. When a clear explanation cannot be identified, it may be useful to speak with a sleep specialist who may be able to provide additional insight. 

Are Light Therapy Glasses Right for Me?

By Brandon Peters, MD

They look a little futuristic, casting a blue light over the eyes and onto the face. In some ways, they are. Light therapy delivered via glasses also relies on science that is as old as time. The use of light therapy glasses may be helpful to manage circadian mood and sleep disorders like seasonal affective disorder (SAD), insomnia, and jet lag. They may offer a boost of energy on a winter morning. How do light glasses work and are they right for you? Learn about phototherapy, circadian rhythms, and the usefulness of artificial light delivered via glasses for several conditions.

What is Light Therapy?

Light therapy, or phototherapy, is the use of light to treat a medical condition. It may be helpful to treat problems that occur when the internal circadian rhythm is misaligned to the natural patterns of light and darkness. This may impact the ability to sleep, the release of hormones including melatonin, and even mood and energy levels.

Light therapy may be done by properly timed exposure to sunlight. Unfortunately, living at northern latitudes may make this more difficult in the winter months. In some cases, an artificial source of light may be needed.

There are certain medical conditions that respond extremely well to this treatment, but how is it delivered?

Light Boxes Versus Light Glasses

Historically, light boxes were used to artificially deliver phototherapy. Initially quite large, the technology has become more portable. In fact, there are now several brands of light glasses that are capable of performing the task:

Ayo

The smallest glasses are available for $299 from Ayo. With a well-integrated app, it is possible to personalize the program by providing information on sleep habits and lifestyle. The light intensity, timing, and duration varies based on the mode and purpose. Boost energy, optimize the sleep-wake cycle, or even beat jet lag and adjust to the new time zone faster. There is some built-in flexibility in the timing of their use. The glasses are comfortable, with a sleek visor-like design that is unobtrusive. It is easy to charge the glasses by placing them in a pill-shaped pod that connects to a computer with a USB cable.

Luminette

For a lower price point, consider the light therapy glasses offered by Luminette. For $199 to buy, or $39 for a trial, similar technology is used to deliver the light therapy directly into the eyes. Unlike a light box, which may require 10,000 lux to be effective, the blue light directed into the eye accomplishes the same treatment with a lesser intensity. There are 3 intensity levels offered: 500, 1000, and 1500. The glasses themselves are larger, broadly situated above the eyes. It is recommended that they be used for 30 minutes daily for best effect.

Re-Timer

Similarly priced, at $199, Re-Timer delivers blue-green light into the eyes for the purposes of phototherapy. Designed to frame the eyes, these glasses were developed at a university based on 25 years of research. It is recommended that the glasses be used for 60 minutes daily, the longest recommended usage of the three models.

Conditions That Respond to Light

The circadian rhythms of the body are mostly affected by exposure to blue light. This part of the light spectrum is present in full-spectrum sunlight. It can also be isolated and delivered at a lower intensity with equivalent effectiveness. What conditions respond best to light therapy delivered via light glasses?

Seasonal affective disorder

Also known as winter depression, it occurs seasonally when the lack of light availability leads to a deterioration of mood. It may be associated with increased sleeping, lack of initiative and social isolation, and changes in appetite and weight gain.

Insomnia

Difficulty falling asleep may be especially responsive to the use of phototherapy. Artificial light exposure in the evening may be a problem, but using light glasses in the morning upon awakening may help to realign the circadian rhythm.

Delayed sleep phase syndrome

Night owls experience this condition that leads to both difficulty falling asleep at a conventional time as well as difficulty waking in the morning at an earlier time. Bedtimes may be at 2 a.m. or later and waking may naturally occur mid-morning or even mid-day. Though it does not necessarily have to be associated with insomnia, it often does when social pressures require sleep-wake timing that is not consistent with this genetic tendency.

Morning sleepiness

Difficulty getting out of bed in the morning due to sleepiness may be relieved with phototherapy. Light naturally wakes us. It initiates the circadian alerting signal. Consistent use in the morning may help to align sleep’s place to the darkness of the night.

Jet lag

In the modern age, jet travel allows a rapid misalignment of the body’s circadian rhythms to the patterns of light and darkness in the environment. It may take one day to adjust to each time zone crossed, but light therapy may make this adjustment occur more quickly. 

Cautions and Side Effects

Phototherapy is generally well tolerated. If it is bothersome, it should be discontinued. Any perceived side effects should resolve once the light glasses are no longer being used. In some cases, the following side effects may occur:

Headaches

Artificial light therapy may trigger headaches or migraines in those predisposed. In this case, a lower light intensity for a more prolonged period may be useful.

Insomnia

Light at the wrong time may lead to difficult sleeping. For example, using light glasses at bedtime may cause a shift in the timing of sleep later. This will make it hard to fall asleep, and hard to wake. Avoid this by following the instructions associated with the light glasses program.

Photophobia

Sensitivity to light may occur. This may lead to pain or simply an aversion to exposure characterized by squinting. It will go away when the light stimulus is removed.

Fatigue

Rarely, fatigue may occur with phototherapy. This may have to do with the changes that occur in the sleep-wake schedule. Following the directions of the program should help to minimize this risk.

Hypomania

For those who have a history of bipolar disorder, light therapy needs to be used with caution. There is a risk that the light may lead to a state of hypomania. This may be associated with an elevated mood, increased productivity, hypersexuality, or other symptoms.

Irritability

Although mood would typically improve with light therapy, in some cases it may lead to irritability. Like the other side effects, it should resolve by stopping the use of the light therapy glasses.

Importantly, there is no ultraviolet (UV) light exposure with the use of light therapy glasses. Therefore, the risks associated with this—such as damage to the eye or cancer—would not be present.

Conclusion

If you are interested in learning more about your sleep, consider evaluation by a board-certified sleep physician. In some cases, consultation with this specialist may optimize your response to the light therapy glasses. Should you experience any problems with their use, seek further assistance by an expert.

Sources:

Peters, BR. “Irregular Bedtimes and Awakenings.” Evaluation of Sleep Complaints. Sleep Med Clinic. 9(2014)481-489.

Reid, KJ and Zee, PC. “Circadian disorders of the sleep-wake cycle,” in Principles and Practices of Sleep Medicine. Edited by Kryger MH, Roth T, Dement WC. St. Louis, Missouri, Elsevier Saunders, 2011, pp. 470-482.

Are You a Night Owl? Delayed Sleep Phase Syndrome Overview

By Brandon Peters, MD

Night owls rule the evening roost. What explains the natural desire to stay up late and sleep in, especially in teenagers? With this overview, discover the causes, symptoms, diagnostic testing, and treatments of delayed sleep phase syndrome. Consider the consequences, including insomnia and sleep deprivation, and what can be done to keep the condition in check.

What Is a Night Owl?

First, how is a night owl defined? Anyone who stays up later than most may be viewed as a potential suspect. However, those with delayed sleep phase syndrome may be birds of a different feather.

If the natural tendency to fall asleep is delayed by at least several hours compared to the average person, with a sleep onset closer to 1 to 3 a.m., this fits the bill. In some cases, the delay may be even more extreme, with a night owl going to sleep closer to sunrise.

The desire to wake up is similarly delayed by at least several hours. Someone who is characterized as a night owl may not desire to wake until 10 a.m. or later. With a sleep onset closer to sunrise, the affected person may not desire to wake until into the early afternoon.

How Common Is Delayed Sleep Phase Syndrome?

It is estimated that 10 percent of the population could be characterized as night owls with delayed sleep phase syndrome. It may be more common among teenagers, who are susceptible to a slight delay in their sleep timing, but it can persist throughout life. There are many retired people who experience the condition once the alarm clock is silenced!

What Causes a Delayed Sleep Phase?

There seems to be a genetic predisposition towards developing delayed sleep phase syndrome. Some of this science is understood. For example, a mutation in the CRY1 gene alters the human circadian clock, delaying sleep by 2 to 2 1/2 hours compared to non-carriers. There will likely be more genes identified that have a role. 

Approximately 40 percent of people with delayed sleep phase syndrome report a family history of the condition.

Beyond genetic programming, there are environmental factors that may unmask the condition. Most importantly, light has powerful effects on the timing of the circadian system. It may provoke the delay in sleep timing, and may also be used to correct the condition.

Understanding the Circadian System and Sleep

Sleep is dependent on two processes: sleep drive and the circadian alerting system. If isolated in a constant environment, like a cave, the genetically determined circadian timing will become evident. It is controlled by the suprachiasmatic nucleus, a region of cells in the hypothalamus of the brain, and highly influenced by light exposure. Every cell, and organ, in the body follows a circadian pattern.

For most people, this internal clock is programmed to run a little long, perhaps resetting every 24 1/2 hours. In the cave, without exposure to light variance, an isolated person would naturally fall asleep and wake 30 minutes later, shifting later each and every day. In a week, the timing of sleep would move 3 1/2 hours. In a month, it would shift 14 hours, so that the person would want to sleep during the natural day and be awake in the natural night. This natural drift in the circadian timing is reset with morning sunlight.

Exposure to natural light in the early morning hours is a signal to the brain for wakefulness. It makes it easier to wake. It also slightly shifts the timing of sleep earlier, making it easier to fall asleep. This helps to align the desire for sleep to the natural period of darkness overnight. Without it, significant problems can develop with sleep and health.

What Are the Symptoms of Delayed Sleep Phase Syndrome?

People with delayed sleep phase syndrome will generally experience two symptoms: insomnia and sleepiness. Why would these seemingly contradictory symptoms occur in the same person? Again, it comes back to a question of when—it comes back to timing. 

Insomnia

Most night owls will experience significant insomnia if they attempt to go to bed earlier than their natural desire for sleep onset. Crawling into bed at 10 p.m. may result in hours of lying awake, tossing and turning. This can provoke anxiety, frustration, and anger—feelings that make the insomnia worse. When left to stay up late on weekends or during vacation breaks, it suddenly becomes much easier to fall asleep.

Morning sleepiness

In the early morning hours, it can be difficult to wake a night owl. It’s like trying to wake the dead. Teenagers have to be dragged out of bed, splashed with water, or roused with threats from despondent parents. This morning sleepiness can be profound. Depending on the hour, it is akin to waking someone with normal sleep timing in the middle of the night. It is extremely difficult to wake and function. By midday, however, the sleepiness abates. When the late evening rolls around, the night owl feels very awake, repeating the cycle again.

Social Pressure Leads to Sleep Deprivation

Unfortunately, night owls are not typically allowed to sleep and wake when their bodies tell them to. If they could always go to bed at 2 a.m. and wake at 10 a.m., there would be no sleep problem. They would fall asleep easily, without insomnia, and wake easily without conflict. Unfortunately, pressure from the rest of society—parents, spouses, bosses, school systems—may be quite disruptive. Without accommodation, chronic tardiness and absenteeism can lead to educational and professional dysfunction.

If someone does not naturally fall asleep until 2 a.m., but has to wake at 6 a.m. to be to work on time, sleep deprivation inevitably results. Unfortunately, 4 hours of sleep is not enough to meet even basic sleep needs. This can have profound effects on health and well-being. Consider some of the symptoms associated with sleep deprivation:

• Sleepiness

• Fatigue

• Difficulty concentrating

• Memory problems

• Mood changes (depression, anxiety, or irritability)

• Errors or accidents

• Physical pain

• Hallucinations

• Paranoia

There is some evidence this can be fatal. This is likely due to the chronic effects of sleep deprivation. One study suggests that people with delayed sleep phase syndrome have a 10 percent higher risk of dying compared to controls.

How Is Delayed Sleep Phase Diagnosed?

With proper education, it becomes fairly easy to recognize night owls who are likely experiencing delayed sleep phase syndrome. It may be a lifelong affliction, starting in adolescence and persisting for decades. How can it be diagnosed?

Fortunately, testing is not required to reach a diagnosis. A careful history by a board-certified sleep physician can typically identify the condition. In some cases, sleep logs kept over weeks may aid the recognition. Rarely is testing with actigraphy needed.

In research settings, the measurement of melatonin levels can help to identify the circadian timing. In particular, the dim light melatonin onset (DLMO) measured via blood or saliva can establish the pattern. Unfortunately, the repeated sampling requires a carefully controlled laboratory environment. This is virtually never done in a clinical practice. More recently, a blood test called TimeSignature has been developed, but it is not widely available.

Treatments of Delayed Sleep Phase Syndrome: Light, Melatonin, and More

If a condition is genetically determined, and potentially lifelong, it may seem like a life sentence. Fortunately, for delayed sleep phase syndrome, this is not the case! There are some effective ways to keep the timing of sleep in a normal phase. It may require a little extra effort, but consider these potential helpful interventions:

Sleep schedule consistency

There is good evidence that night owls can maintain a socially acceptable sleep timing. This requires consistency, especially in regard to the wake time. Get up at the same time every day, including weekends. Do not sleep in. Go to bed feeling sleepy, even if this initially requires a delay in the preferred bedtime. This will make it easier to fall asleep faster, relieve pressure to sleep, and reinforce the sleep quality.

Morning sunlight

It is especially important to reset the timing of sleep with morning sunlight. This is most effective immediately upon awakening. Try to go outside for 15 to 30 minutes upon awakening. Wake with an alarm, throw on clothes, and immediately get outside. Take a walk. Read the newspaper in the garden. Check social media while facing the sunrise. Light should hit the eyes, but don’t stare directly into the sun. Even a cloudy or rainy day, try to stick to the routine. In winter months, a light box may be necessary for phototherapy. The effects may take up to 1 month to become evident.

Avoid light at night

Artificial screen light should be minimized at night, especially in the hours preceding bedtime. It may shift the timing of sleep to occur later, causing insomnia and morning sleepiness. Devices may be switched to night mode, cutting out the blue light that can shift sleep timing. Blue blocker sunglasses (with an amber tint) or screen covers may be employed. Best yet, simply shut down the electronics in the 2 hours before bedtime. The buffer zone before the goal bedtime should be spent relaxing.

Melatonin

Melatonin is a hormone produced overnight by the pineal gland in the brain. It can be an external signal to the circadian system, most effective among the blind. If taken up to 6 hours before the desired bedtime, it may help night owls to fall asleep earlier. The effects may be somewhat weak, and certainly overpowered by the effects of light.

Cognitive behavioral therapy for insomnia (CBTI)

This effective treatment helps to improve the patterns of sleep and one’s relationship to it. Sleep consolidation, stimulus control, mindfulness, and relaxation techniques may be integrated into a program. It may be guided with help from a psychologist, class, online course, or book.\

Chronotherapy

Rarely, it may be necessary to adjust the timing of sleep incrementally in a structured environment. It is difficult to carry out at home and may require hospitalization. Over successive days, the sleep period may be delayed by 1 to 2 hours until the desired timing of sleep is achieved. Poorly timed light may complicate the efforts, and strict adherence to the final schedule must be observed.

Prescription medications

Sleeping pills and stimulant medication to enhance alertness have a limited role in this condition. Generally, they will be weakly effective. As a result, they may be overused and even abused. The risk of overdose in night owls, especially when these medications are used in combination with alcohol, is high. Instead of masking symptoms with a drug, the underlying timing of the circadian rhythm should be corrected.

Social awareness

Education may help parents to appreciate what their teenager is experiencing, to know that it is not laziness or defiance. High schools should continue to accommodate this natural timing among their students by shifting the school day. Later school start times enhance academic performance, reduce tardiness and truancy, and even diminish car accidents among teens. 

Conclusion

Sleep deprivation can have serious impacts on health and well-being. If you are struggling with delayed sleep phase syndrome, consider seeking the guidance of a board-certified sleep physician. Start with some simple advice: Go to bed feeling sleepy (even if later), keep a consistent wake time, and get sunlight upon awakening. If more help is needed, seek it out.

How the Best Sunrise Alarm Clocks Make Waking Easier

By Brandon Peters, MD

It is pretty normal to use an alarm clock to wake up. What is not as common, however, is for the clock to mimic a sunrise and wake you with a gradually increasing amount of light. How do the best sunrise alarm clocks make waking easier? Learn how a dawn simulation light works, why it might be preferable to an audible alarm, who benefits most from its use, and what alternatives exist that may help to enforce a circadian pattern, easing insomnia and making it easier to wake and get up.

What Is a Sunrise Alarm Clock?

A sunrise alarm clock, or dawn simulation light, is an artificial light source that is integrated into a standard digital clock. It is timed to gradually wake a person at a selected time. It does this by mimicking the steadily increasing light of sunrise, often over 30 to 40 minutes, but some models may allow the timer to be adjusted from 15 to 60 minutes.

These simulators may have a full-spectrum white or yellow LED lightbulb. The color spectrum, or color temperature (think of this as the “warmth”), of this light may vary slightly from one model to the next. Most are of modest intensity, often 100 to 300 lux, with less light than a standard light box.

There are a variety of models, most costing less than $25 to $100, including:

• Philips Wake-Up Light HF3520

• Philips HF3505

• Philips Somneo HF3650

• hOmeLabs Sunrise Alarm Clock

• Mosche Sunrise Alarm Clock

• INLIFE Wake Up Light Alarm Clock

• NATPLUS Sunrise Alarm Clock

• iHome Zenergy Bedside Sleep Therapy Machine

• totobay

• Sharp Sunrise Simulator

• Lumie

The add-on features also vary widely from one product to the next. Many have the ability to adjust the light intensity, snooze features, and associated standard alarm sounds or music. There may be USB ports integrated for charging devices. Beyond encouraging a gradual awakening, some can even dim light gradually (a so-called sunset feature), making it feel more natural to fall asleep.

How Do Dawn Simulation Lights Work?

Dawn simulation lights can make it easier to wake, but how do these devices work? It is important to consider the natural patterns of light and darkness and how the circadian rhythm enforces optimal sleep and wakefulness.

Humans, like most animals, have evolved to sleep overnight during darkness. Light, conversely, has a waking effect on the brain and body. It suppresses melatonin and activates the circadian alerting signal. Light at the wrong time, like from a screen prior to bedtime, may make it hard to fall asleep and contribute to insomnia. In the morning, when incorporated into a sunrise alarm clock, it may make it easier to wake.

Light exerts this impact by traveling from the eyes via the optic nerves to an area of the brain that regulates the body’s circadian rhythm. This area of the brain, called the suprachiasmatic nucleus, lies in the hypothalamus. It is the master clock of the body. Without it, the patterns of sleep and wakefulness, metabolism, hormone release, cortisol levels, body temperature, and other processes would run amok.

Fortunately, light at the proper time may help us to sleep and feel better. Even artificial light, if appropriately timed, may enforce the normal patterns of our body that would exist if we slept in a perfectly natural environment. A gradual increase of light in the morning hours, even in the natural darkness present in winter months at northern latitudes, may reinforce a normal pattern of waking.

Why Is Light Better Than Sound?

The sudden, blaring sound of an alarm clock will definitely wake someone. However, this abrupt shift from sleep to wakefulness can be disorienting. If full wakefulness is not attained, the snooze button may be pressed and sleep may quickly resume. Short awakenings, such as those lasting less than 5 minutes, may go unremembered. If the alarm clock is simply turned off—or smashed into 1,000 pieces—trouble may ensue!

Light may wake a person more gently and more gradually. The transition from sleep to wakefulness is more orderly. This may help to relieve sleep inertia, that profound sense of sleepiness that is difficult to shake when first opening your eyes. It is something that feels more natural. The sky does not go from pitch black to glaring sunshine. As the sun creeps over the horizon, the amount of light hitting our eyes (even through closed eyelids) steadily increases. It may reach a threshold where it finally wakes us. This may make it less likely a person would want to hit snooze repeatedly and fall back asleep. Even the thought of it seems more pleasant.

Who Should Consider a Sunrise Alarm?

Although there are certain groups who may benefit more from using a sunrise alarm, scientific research suggests that many of us could yield positive health impacts.

There are a surprising number of important benefits from the use of dawn simulation lights. Research suggests it may:

• Improve cardiac function and reduce the risk of heart attacks

• Provide a boost to the brain’s function (in select cognitive domains)

• Enhance performance in tasks done immediately after waking

Clearly there are certain conditions or groups of people who would likely enjoy the effects of a sunrise alarm even more. Consider these possibilities:

Night owls

Delayed sleep phase syndrome is a circadian disorder characterized by difficulty initiating sleep (insomnia) and profound morning sleepiness. It affects 10 percent of the population, usually starting in the teenage years. Most night owls feel naturally sleepy close to 2 a.m. and may not naturally wake until 10 a.m. The use of a dawn simulation light may make waking a little easier. In some cases, a light box may be more effective to reinforce an earlier circadian phase.

Winter depression

Seasonal affective disorder, or winter depression, impacts people living in northern latitudes during the winter months when the nights are long and the days are short. Darkness can make it hard to wake in the morning. This may lead to increased depressive symptoms, lethargy, prolonged sleep, weight gain, and other symptoms. An artificial light may help the morning to start a little easier.

Teenagers

As noted above, teenagers are susceptible to delayed sleep phase syndrome. As a general rule, teens are more likely to have a slight delay in sleep timing, even with a less profound shift in the pattern. This can make it hard for adolescents to fall asleep at a desirable time. It can also make it very difficult to wake them in the morning. This can lead to early morning fights with parents, tardiness, absenteeism, and other problems like car accidents, inattention, and academic failure. Consider how desirable it might be to have a gentle light do the waking, and let the drama of the morning fade away.

Shift workers

Those who work atypical shifts—second, third, graveyard, rotating, or even call coverage—are subject to many sleep problems. When the desire for sleep and wake is forcibly misaligned from the patterns of darkness and light, it can be difficult to function optimally. This may lead to increased errors, accidents, and health problems (including a higher risk for cardiovascular disease, weight gain, and breast and colorectal cancers). Artificial light, if properly timed, may help to alleviate some of this misalignment.

Jet lag 

For every one time zone crossed, it can take one day to adjust the circadian rhythm. Traveling across a continent, or an ocean, can lead to significant disruption. The use of a sunrise alarm clock may make this transition easier. The optimal timing of this light exposure will depend on the distance traveled, and whether preparation was made prior to departing on the trip.

Hearing impaired

Finally, those with a hearing impairment may benefit from using a light to wake, rather than an audible alarm. The deaf may otherwise need to rely on others to wake on time. The use of a sunrise alarm clock may provide a new degree of independence.

Alternatives to Sunrise Alarm Clocks

Many people will be attracted to the possibility of easing insomnia and waking and getting up easier. Not everyone may want to use a sunrise alarm clock, however. There may be a handful of alternatives to consider. Consider how these additional options may make it easier to wake in the morning:

Natural sunlight

Throw the window shades open in your bedroom before retiring for the evening. This will let in natural light. After sunrise, the light will be able to stream through the windows and promote wakefulness. Unfortunately, this may not be ideally timed certain times of the year.

Light box

Consider a light box with 10,000 lux of intensity. It is powerful enough to shift the circadian rhythm, benefiting seasonal affective disorder as well.

Light therapy glasses

For those with a little extra buying power, light therapy glasses are a convenient and effective option. With a lower amount of light, shone directly into the eyes, these glasses can make it easier to wake.

Caffeine

A cup of coffee or tea can make it easier to get the morning started. Caffeine blocks adenosine, a signal for sleep, within the brain. With a half-life of 4 to 6 hours, it can get you through the morning.

Get motivated

Consider ways to motivate yourself out of bed. Morning exercise, quickly hopping in the shower, a special breakfast, or stepping outside to enjoy the early light may be helpful. In some cases, scheduling something you really enjoy for first thing in the morning may do the trick. 

Conclusion

There are many effective ways to wake and feel refreshed. A sunrise alarm clock may help to ease the transition to wakefulness. If you consistently struggle to wake, or have sleep of poor quality, consider getting evaluate by a board-certified sleep physician. Sleep disorders can be effectively resolved to the benefit of your health and well-being.

Sources:

Follum JD, Catchpole JM. “Sunrise alarm clock for the hearing impaired.” Biomed Sci Instrum. 2011;47:18-23.

Viola AU et al. “Dawn simulation light: a potential cardiac events protector.” Sleep Med. 2015 Apr;16(4):457-61. doi: 10.1016/j.sleep.2014.12.016. Epub 2015 Feb 26.

Gabel V et al. “Dawn simulation light impacts on different cognitive domains under sleep restriction.” Behav Brain Res. 2015 Mar 15;281:258-66. doi: 10.1016/j.bbr.2014.12.043. Epub 2014 Dec 27.

Thompson A et al. “Effects of dawn simulation on markers of sleep inertia and post-waking performance in humans.” Eur J Appl Physiol. 2014 May;114(5):1049-56. doi: 10.1007/s00421-014.2831-z. Epub 2014 Feb 11.

The Science of Circadian Rhythms

By Brandon Peters, MD

Circadian rhythms may be the most difficult concept to understand in the world of sleep medicine. There is a lot of confusing language, and it relies on science that is not easily approached. Fortunately, a basic understanding of the science of circadian rhythms can be obtained and may help to explain some cases of insomnia and daytime sleepiness.

As the World Turns

The Earth’s 23 hour and 56 minute daily rotation provides predictable rhythms of light and temperature, food, and predator activity. Through adaptive evolution, our body’s metabolism and even our behaviors are programmed to respond to this precise timing. Franz Halberg coined the term circadian (from the Latin meaning “about a day”) in 1959. It describes numerous approximately 24-hour cycles that are generated within nearly every organism on the planet.

Within our body, there is a system in place that measures time and synchronizes many internal processes to daily events within the environment. Some of these important processes include:

• Sleep and wakefulness

• Metabolism

• Core body temperature

• Cortisol levels

• Melatonin levels

• Other hormones (growth hormone, thyroid hormone, etc.)

The control of these patterns is built into our genetic makeup; the machinery synchronizes rhythms that will persist independently of outside influences. The first mammalian gene, Clock, was identified in 1994. Multiple additional genes have been identified that constitute a core molecular clock that gives rise to other cellular, tissue, and organ function.

Every cell in our body follows a circadian pattern: an extraordinary symphony of biochemical reactions that are perfectly timed based on available resources and orchestrated by a small group of cells in the anterior part of the brain’s hypothalamus. Through hormones and other as yet undetermined influences, the central pacemaker coordinates peripheral clocks that are present in cells as diverse as cardiac, liver, and adipose tissues.

Light is perceived by the eyes and travels via the retina to the optic nerves. Above the optic chiasm, where the two optic nerves cross behind the eyes, sits the suprachiasmatic nucleus (SCN). This is the master clock of the body. It couples the numerous physiological processes described to the timing of light and darkness in the environment.

These patterns will persist without external time cues, but they may vary slightly from the geological day length. As a result, in isolation from resetting cues, the timing of these processes may gradually become desynchronized. The degree of shift may depend on our genetic program, or tau, with most people having an internal clock that runs longer than 24 hours. It is understood that our genetics and the interaction with other environmental factors – especially the exposure to morning sunlight – may have important effects on resetting the internal clock. These external influences are called zeitgebers, from the German for “time-givers”.

When the internal clock is misaligned to our environment, circadian disorders such as delayed and advanced sleep phase syndrome can occur. With a complete disconnect from light perception, as occurs in total blindness, a Non-24 rhythm occurs. These conditions are often associated with insomnia and excessive daytime sleepiness as well as irregularities in the sleep-wake rhythm that cause social and occupational dysfunction.

Fortunately, treatment of circadian disorders can be highly effective and a board-certified sleep physician can provide helpful guidance and resources.

Sources:

Borbely, AA. “A two process model of sleep regulation.” Hum Neurobiol. 1982;1:195-204.

Czeisler, CA et al. “Bright light resets the human circadian pacemaker independent of the timing of the sleep-wake cycle.” Science. 1986;233:667-671.

Lewy, AJ et al. “Phase shifting the human circadian clock using melatonin.” Behav Brain Res. 1996;73:131-134.

Moore RY and Eichler, VB. “Loss of a circadian adrenal corticosterone rhythm following suprachiasmatic lesions in the rat.” Brain Res. 1972 Jul 13;42(1):201-206.

Moore-Ede, MC et al. “A physiological system measuring time, “ in The Clocks That Time Us. Cambridge, Massachusetts, Harvard University Press, 1984, p. 3.

Peters, BR. “Irregular Bedtimes and Awakenings.” Evaluation of Sleep Complaints. Sleep Med Clinic. 9(2014)481-489.

Piggins, HD. “Human clock genes.” Ann Med. 2002;34(5)394-400.

Reid, KJ and Zee, PC. “Circadian disorders of the sleep-wake cycle,” in Principles and Practices of Sleep Medicine. Edited by Kryger MH, Roth T, Dement WC. St. Louis, Missouri, Elsevier Saunders, 2011, pp. 470-482.

Richardson, G and Malin, HV. “Circadian rhythm sleep disorders: pathophysiology and treatment.” J Clin Neurophysiol. 1996;13:17-31.

Sack, RL and Lewy, AJ. “Circadian rhythm sleep disorders: lessons from the blind.” Sleep Medicine Reviews. 2001;5(3):189-206.

Vitaterna, MH et al. “Mutagenesis and mapping of a mouse gene, Clock, essential for circadian behavior.” Science. 1994;264(5159):719-725.

How to Use Fitness Trackers for Sleep Improvement

By Brandon Peters, MD

If you have purchased a fitness tracker, like millions of others, you may wonder how to use the wearable device to improve your sleep. These sleep trackers may provide some valuable insight into an important of health and well-being. They can also be completely useless. What do these wearables measure? How accurate are these measurements? How do they differ from medical sleep studies? Importantly, how should the information collected be used to make changes to improve sleep and reduce insomnia? Let’s consider these important questions and discover how to use fitness trackers to sleep better.

What Sleep Metrics Do Wearable Fitness Trackers Measure?

There are many wearable devices available that can be used to track fitness goals and even sleep. Some of the most popular options include the FitBit and Apple Watch. There are also smartphone apps, smart beds, mattress pads, and stand-alone products that can track sleep metrics. What kind of information is collected?

Movement

Most devices are tracking movement. There are variations on actigraphy. This measures movement velocity and direction with an accelerometer. It may be assumed that stillness equates with sleep, and movement corresponds with activity.

Biometrics

Sophisticated devices may detect breathing patterns, heart rate, or oxygen levels. It may even be possible to measure electrical current conductivity within the skin. Sound may also be detected, sometimes via vibration, that may correspond with snoring.

Schedule

Timing is important to sleep quality. It may also be possible to input information about your bedtime, wake time, and even naps to help track sleep patterns over an extended period. This information is often collected via sleep logs and may help to identify circadian rhythm disorders.

Environmental Characteristics

Some devices may also be able to identify other environmental characteristics, such as lighting, temperature, and noise. These may be useful to support the other variables that are measured. If the room is dark, it is nighttime, and a person is not moving, it is more likely that they would be asleep.

How Accurate Are Sleep Trackers?

It is natural to wonder how accurate sleep trackers are in measuring the characteristics of sleep. If you were dieting and using a scale, you would certainly want to ensure the weight that it was reporting was close to reality, both true to the actual value (accuracy) and repeatable over time (precision).

Sleep is more than just lying still. Someone could lie perfectly still and a wearable may believe this inactivity corresponds to sleep. Similarly, movements may occur during sleep that do not necessarily correspond with complete wakefulness. Many awakenings will go unnoticed by an individual as it can take more than 5 minutes of wakefulness before a memory is generated.

It is possible that other measurements may help to strengthen the accuracy of these observations. Breathing becomes very regular in deep, slow-wave sleep. This may indicate a person has fallen asleep. Heart rate patterns, oxygen levels, and other biometric measurements may help improve accuracy.

Unfortunately, many sleep trackers are products that are designed for consumers without scientific validation. The measurements may not be either accurate or reproducible. Artifact may interfere with the measurements. Moreover, the collected information may not correspond to the gold standard measurements.

Comparing Information to Sleep Testing and Studies

When sleep is measured by a diagnostic polysomnogram in a sleep center, there are a number of important characteristics. These include the brain wave activity as measured by EEG, muscle tone, the movement of eyes, other body movements, and sometimes additional data. No fitness trackers are able to collect all of these data. The nightly sleep patterns they provide—showing light, deep, and even REM sleep—are not as accurate as the information gathered with formal sleep testing.

In fact, sleep trackers are perhaps closest to an actigraph, a small wristwatch-like device that measures movement to give a rough pattern of sleep and wakefulness. These data can be very difficult to interpret, even by expert researchers, and the messy signals may be inscrutable to an algorithm. What is a person to do? How can you use the data that is collected via a wearable sleep tracker to optimize your sleep?

How to Use Data to Improve Sleep

Though the data collected by wearables or other sleep trackers may be imperfect, it can still be useful. It may be important to take a bird’s eye view of the information that is collected. Consider these simple recommendations:

1. Trust your own experiences.

Before buying into the data collected by an imprecise, and possibly wholly inaccurate device, reflect on your own sense of how you are sleeping. Do you recall waking 30 times in the night? Do you remember dreaming, even though the device reported no dream sleep? Are you having difficulty explaining the sleep pattern it provides? If you feel like you are sleeping well, consider simply ignoring the sleep data your device may provide.

2. Use the information to reinforce good sleep habits.

It is helpful to keep a regular sleep-wake schedule. Get up at the same time every day, including weekends. Try to get 15 to 30 minutes of sunlight upon awakening. Go to bed at about the same time every day. Go to bed when you are feeling sleepy. Try to get at least 7 to 9 hours of sleep nightly, meeting your own sleep needs. Avoid naps when possible. If the sleep tracker helps to reinforce a regular schedule, it may be useful.

3. Don’t sweat the details.

There is evidence that data collected by sleep trackers can stress people out. It can add to anxiety and make insomnia worse. People become obsessed with the details, trying to explain every little blip in the data. If you find this is leading to obsessive behaviors for you, this could be a problem. Let it go. It may not be accurate anyway.

4. Corroborate the data with witness testimony.

There may be some inexplicable findings from your sleep tracker data. Perhaps some unremembered steps accumulated in the night. There may be frequent awakenings or restless sleep. The device may even report loud snoring. Try to verify these reports by asking a witness: consider questioning a bed partner. Learn if you sleepwalk, restlessly toss in the night, or rattle the windows with snoring. If there is a discrepancy, consider gathering more information before jumping to any conclusions.

5. If you are not sleeping well, get help.

Many people use sleep trackers because they are not sleeping well. They are hopeful that they may learn a little bit about why they are having difficulty sleeping. If the insomnia persists, this search can become desperate. Although some insight may be gleaned, more evaluation may be necessary. If you have poor sleep, especially if you have trouble sleeping through the night with frequent awakenings or experience daytime sleepiness, get evaluated by a board-certified sleep physician to sort out what might be contributing to your troubles.

Conclusion

It is fun to learn about ourselves. Sleep can be mysterious. Most of the night goes unremembered. It is natural to want to lift the curtain and glimpse a little about what occurs once our eyes close and we fall asleep. Be careful about positing too much faith into the accuracy of sleep trackers. The technology may improve with time, but these devices may be more novelties than serious scientific analyses. If you are struggling to sleep, get help from an expert.

How to Take Melatonin

By Brandon Peters, MD

Melatonin is a naturally occurring hormone that is often taken in a pill form as an over-the-counter supplement to aid sleep. It is most helpful in circadian rhythm sleep disorders, but it is frequently taken to alleviate difficulty falling or staying asleep (characteristic symptoms of insomnia). If you are interested in using melatonin to help you to sleep, you may wonder how to take melatonin, as well as the appropriate dose and timing.

What Dose of Melatonin Should I Take?

Melatonin is believed to be relatively safe and it is therefore available over-the-counter at many pharmacies and health supplement stores. It may be compounded in multiple different ways, and it is sometimes even added to other products meant to aid sleep. Pure melatonin is most often sold as a pill or capsule, but you can also buy it in a liquid or even spray form.

The advertised strength of the melatonin dose may range from 1 mg up to 10 mg or more. It is important to remember that melatonin is not regulated by the Food and Drug Administration (FDA). As such, production and quality standards are not enforced, so the dose may actual vary from the listed strength.

Research suggests that even quite low doses of melatonin may be effective, especially in circadian rhythm disorders. The relationship between the dose and the perceived effect -- a so-called dose-response relationship – does not appear to exist for melatonin. Therefore, it is difficult to determine the optimal dose for an individual. Given these limitations, it is probably best if you take the lowest possible effective dose. (This would mean taking 1 mg or 2 mg to aid sleep.) If you take too much, you may actually flood your system and the benefits will be counteracted. The timing of the dose is very important and high blood levels at the wrong times may be a problem.

When Should I Take Melatonin?

The role of melatonin in regulating our biological clock, or circadian rhythm, appears to be critical. Therefore, the timing of when you actually take it is just as important. It is normally produced in part of the brain called the pineal gland and is released during the period of darkness from sundown to sunrise. When taken as an oral supplement, it reaches a maximum concentration in your blood after 30 minutes. However, the timing of administration may not be quite so simple.

Most people should take melatonin in the evening before going to bed, but -- curiously -- there are others who should actually take it in the morning. How do you know when you should take it? If you have trouble falling asleep (especially if you want to stay asleep in the morning), you should take it at night. However, if you have no trouble falling asleep but you awaken too early in the morning, you should actually take it in the morning. (As an aside, you should also ensure that you have ample light exposure at the opposite time from when you take your melatonin.)

Now that you have figured out whether to take it in the morning or at night, how close should you take it to your desired bedtime (or after awakening)? If you decide to take it at night, you should take it 3 hours before your desired bedtime. Conversely, if you are falling asleep and awakening too early, you may take it 3 hours after waking.

Is It Safe to Take Melatonin Every Night?

As described above, melatonin is extremely safe. It is a hormone that your body makes naturally. Its use in a supplement form is also believed to be quite safe. It is not habit forming and you will not become “addicted” or dependent upon it. Therefore, if you find it to be helpful in improving your sleep, you may use it on a nightly basis without fear of adverse consequences.

Source:

Kryger, MH et al. "Principles and Practice of Sleep Medicine." Elsevier, 5th edition, pp. 916-920.

What Is Jet Lag?

By Brandon Peters, MD

Jet lag is a circadian disorder that transiently occurs after rapid travel across multiple time zones. It may be associated with other physical symptoms, including disturbed sleep. Learn about this common condition, its symptoms, and potential treatments.

If you have ever flown across a few time zones, you are undoubtedly familiar with the struggles of adjusting your sleep to the new hours. Why is jet lag, as it is called, so hard to tolerate and is there anything to be done?

First, it should be recognized that your body wishes to keep a regular sleep schedule. Certainly we are creatures of habit, and our bodies like when we go to bed and get up at the same time every day. Our biological clock, which is controlled by part of the brain called the suprachiasmatic nucleus, helps us to keep a regular schedule by releasing hormones on a regular pattern. This pattern is called a circadian—or “near day”—rhythm. Our sleep follows this same regular pattern.

When we disrupt the regularity of these cycles, our body treats us unkindly by making us sleepy or alert when we don’t wish to be. For example, if you were to go to bed three hours early tonight, you would have great difficulty falling asleep. However, if you fly from California to New York and crawl into bed at your normal bedtime, you are effectively attempting the same thing.

Causes

Rapid travel across multiple time zones leaves the circadian rhythms out of sync with the destination’s light-dark cycles. These rhythms affect sleep and wakefulness as well as metabolism, body temperature, and hormone release. It can take time for the internal circadian rhythm to be re-synchronized to external time cues. Jet lag is sometimes called desynchronosis, referring to the misaligned sense of time.

As a general rule, it is possible to adapt at an average rate of 1 hour per day. For someone who lives in California to fly to New York and cross three time zones, it would usually take 3 days to adjust to the new time zone. It is generally easier to travel westward and harder to travel eastward for most people.

Social jet lag may cause less intense symptoms and occurs in people who delay their bedtime and wake time by 1 to 2 hours on weekends and then have to correct as the work week resumes on Monday. This shift in the circadian timing may affect the start of the work week for several days.

Significance

In the new location, circadian signals may conflict with environmental and social cues in the context of jet lag. This may lead to a constellation of symptoms, including:

• Excessive daytime sleepiness

• Fatigue

• Insomnia

• Irritability

• Poor concentration

• Digestive problems (dyspepsia)

• Malaise (feeling unwell)

These symptoms may be disruptive and may be exacerbated by sleep deprivation, dehydration, sleep environment changes, and stress associated with travel.

Testing

The presence of the typical symptoms in the context of jet travel confirms the diagnosis without the need for further testing. In research, it is possible to measure an individual’s circadian pattern with tests that detect melatonin levels, often sampled from repeated saliva measurements. There are new blood tests also coming into clinical use that may identify the circadian rhythm.

Associated Conditions

Jet lag is most commonly associated with insomnia, defined as difficulty falling asleep or returning to sleep after waking. If insomnia occurs for less than 3 months, it is termed acute insomnia. As most people would be taking trips of a shorter duration than this, it could be grouped with other briefer disturbances of sleep. In some cases, jet lag may trigger a disruption that may evolve into a chronic form of insomnia.

Treatment

How can we counter our circadian rhythm when we travel? There are several techniques to reduce the effects of jet lag.

One solution would be to keep the same hours as our original time zone, going to bed and getting up based on the times at home.  his may not be the best way to enjoy our travels, especially if we fly great distances. An alternative would be to slowly adapt to the new time zone prior to leaving.

It may be possible to prepare the body gradually prior to departure by slowing adjusting bedtime and wake time to match the destination’s time. This can be done by adjusting our sleep by an hour for a week at a time. If we are crossing two time zones, the change can occur over two weeks. If traveling west, we would go to bed and get up an hour later for one full week. During the second week we would repeat the same, going to bed and getting up another hour later. If traveling east, we would go to bed and get up an hour earlier each week. If we can slowly adapt to the change, we will tolerate it better.  Unfortunately, unless the trip is quite lengthy, we wouldn’t be able to adjust the other way for our return home.This adjustment may be enhanced with properly time light exposure.

Light is one of the primary synchronizers of the circadian rhythm in sighted individuals. It may advance the timing of sleep earlier if the light exposure occurs in the 2 hours prior to the normal wake time or immediately upon awakening. Sunlight is best, but the use of light boxes or light therapy boxes may also have a role.

Beyond light, it may be important to address the symptoms that occur. Caffeine or strategic napping may relieve sleepiness. Other stimulant medications could also have a role. It may also be helpful to use hypnotic medications to aid sleep, including over-the-counter melatonin or prescription pills, such as:

• Zolpidem (Ambien)

• Eszopiclone (Lunesta)

• Zaleplon (Sonata)

• Ramelteon (Rozerem)

These medications to aid both wakefulness and sleep may ease the transition to a new time zone.

Conclusion

If you have a big trip coming up, you might plan ahead in how you can adjust your circadian pattern of sleep and wakefulness with some of the interventions outlined. This may help to optimize your experience while traveling to avoid the symptoms of jet lag.

Sources: 

Drake CL and Wright KP. Shift Work, Shift-Work Disorder, and Jet Lag. Principles and Practice of Sleep Medicine, 6thed., Philadelphia, Elsevier, 2017. pp.714-725.

American Academy of Sleep Medicine. International Classification of Sleep Disorders, 3rd ed. Darien, IL: American Academy of Sleep Medicine, 2014.

Gooley JJ. Treatment of circadian rhythm sleep disorders with light. Annals of the Academy of Medicine, Singapore. 37(8):669-76, 2008 Aug.

Sack RL. The pathophysiology of jet lag. Travel Medicine & Infectious Disease. 2009 Mar;7(2):102-10.

Sack RL. Circadian rhythm sleep disorders: part I, basic principles, shift work and jet lag disorders. Sleep. 30(11):1460-83, 2007 Nov 1.

Srinivasan V, et al. Jet lag: therapeutic use of melatonin and possible application of melatonin analogs. Travel Medicine & Infectious Disease. 6(1-2):17-28, 2008 Jan-Mar.

How Long Should You Wait Between Screen Light Exposure and Going to Bed?

By Brandon Peters, MD

There is some concern that light exposure at night may affect sleep. What is the evidence that artificial light from screens contributes to insomnia? How long should you wait between screen light exposure and going to bed? Explore this relationship and some of the science behind the rationale.

The Science of Sleep

When considering how optimal sleep occurs, it is important to understand the two primary contributors: homeostatic sleep drive and circadian rhythm. Sleep drive is the fact that the longer you stay awake, the sleepier you will become. This is due to a chemical that gradually builds in the brain with prolonged wakefulness. This chemical is called adenosine. High levels of adenosine contribute to the onset of sleep. Sleep, at least in part, is a process of clearing this chemical away until consciousness is restored. Interestingly, caffeine blocks this signal and alcohol enhances it.

The circadian rhythm is the complement to this system. It is predominately an alerting signal that strengthens during the daytime and is largely absent overnight. It becomes strongest in the late evening hours, when we would expect to feel fairly sleepy. There is a lull in the mid-afternoon, which can contribute to a desire to take a nap then.  The circadian rhythm is based in our genetics, persisting without external influences. It contributes to sleep-wake propensity, hormone release, and metabolism. These processes are linked to the day-night cycle of light and darkness via the eyes.

How Light Changes Sleep

A simple anatomy lesson reveals the importance of light exposure to sleep. The eyes perceive light via the retina and pass this information along the optic nerves, extensions of the brain itself. These optic nerves receive input from each eye and cross at a location called the optic chiasm. Just above this is an area of the brain called the hypothalamus, a functional area that is integral to the control of the processes described above.

Within the hypothalamus lies the suprachiasmatic nucleus. This is the control center of the body’s circadian rhythm. It is the central pacemaker, coordinating the activities of all the body’s organs, tissues, and cells. Therefore, light input can be directly linked to the influence of many of the body’s processes.

In particular, light exposure can suppress the desire for sleep. Morning sunlight exposure may help to wake us, initiating the circadian alerting signal. In the same way, artificial light at night may affect the timing of sleep. It may contribute to insomnia in susceptible individuals, especially among those with a tendency towards being a night owl (called delayed sleep phase syndrome).

Preserving Darkness in the Night

What impact did Thomas Edison have on sleep in inventing the light bulb? As society has evolved, the potential disturbances have only expanded. With electricity, our evenings are filled with activity: televisions, computers, tablets, e-books, and phones that flicker light into our eyes. Moreover, the activity itself may keep us awake, shorten our total sleep time, and interfere with a relaxing buffer zone before bedtime. There is some evidence that light at night may adversely affect sleep.

Research has demonstrated that in the spectrum that we perceive as light, the blue wavelength is the one that can change our circadian rhythms. Therefore, industries have developed to supply filters and glasses that block the blue light. It seems that even short bursts of light, especially when of higher intensity, can impact sleep’s timing.

The sun is much more powerful in intensity compared to light from bulbs or screens. Full sunlight may be 100,000 lux in intensity while overhead lights may be just 1,000 lux. Therefore, a blast of sunlight at night could profoundly impact sleep. For susceptible individuals, artificial light may also negatively impact sleep onset and contribute to insomnia.

As a result, it is recommended that people who have difficult falling asleep may benefit from reduced light exposure prior to bedtime. Preserve the last 1 hour, and perhaps longer in highly sensitive individuals, as an electronics-free zone. Power off your screens, especially those that are closer to your eyes. It is also advisable to keep your bedroom free of electronics to preserve sleep. This is especially important advice for teens and children.

Why might some people not be bothered by light at night? The complement system, characterized by sleep drive and building levels of adenosine, could counteract these effects. If you are sleepy enough, you may not be bothered by the light. If you struggle with persisting insomnia, consider speaking with a sleep specialist to help determine ways for you to improve your sleep.

How Being in College Can Disrupt Sleep

For many students, starting college is like stepping into an entirely new world. There’s a new living environment, new social opportunities, academic challenges, and often a level of independence they’ve never experienced before. While these changes can be exciting, they can also wreak havoc on one of the most important — and underrated — foundations of well-being: sleep.

College life, for all its energy and activity, is a perfect storm of factors that make it easy to push bedtime later, cut rest short, and live in a cycle of fatigue. And while an occasional late night is part of the college experience, chronic sleep disruption can have serious consequences for health, mood, and academic success.

Why Sleep Is So Vulnerable in College

College students are technically adults, but their sleep needs remain similar to late teens: most still require 7–9 hours per night to function optimally. Unfortunately, surveys show that many college students average only about 6–6.5 hours on school nights, and they often catch up on weekends — creating an irregular schedule that throws off the body’s internal clock.

Several intertwined factors contribute to the disruption:

1. A Shift in Autonomy

In high school, many students had parents reminding them to go to bed, limiting screen time, and enforcing wake-up schedules. In college, that external structure disappears. Students set their own bedtime, often guided more by social plans or looming deadlines than by biological needs.

2. Irregular Class Schedules

Unlike high school’s consistent timetable, college schedules can vary wildly. One day might have an 8:00 a.m. lecture, while the next has the first class at 1:00 p.m. This inconsistency makes it tempting to stay up late on “light” days and sleep in, which can shift the sleep cycle later and make early mornings harder.

3. Academic Pressures and Workload

College courses often require more independent study, heavier reading loads, and larger projects. It’s easy for work to spill into late-night hours — especially when procrastination or underestimating assignments comes into play. For students balancing jobs or internships on top of classes, evenings may be the only time left to study, pushing bedtime further back.

4. Social Opportunities at All Hours

One of the joys of college life is the ability to hang out with friends whenever you want — whether that’s watching movies at midnight, attending campus events, or going out. Many social activities take place in the evening or late at night, creating a constant temptation to stay up past a healthy bedtime.

5. Living Environment

Dorms and shared apartments are rarely havens of quiet. Roommates may have different schedules, and communal living can mean noise in the hallways, shared bathrooms, and late-night conversations just outside your door. Even students who want to sleep may find it challenging in a bustling residence hall.

6. Technology and Screen Time

Laptops, smartphones, and gaming consoles are ever-present in college life. Not only can they consume hours that could be spent sleeping, but the blue light from screens delays the release of melatonin, making it harder to fall asleep. Students who scroll through TikTok or game until 2:00 a.m. may not feel sleepy even if they know they should.

7. Substance Use

Caffeine is a staple for many students — from morning coffee to late-night energy drinks — but too much, especially in the afternoon or evening, can make it hard to wind down. Alcohol, while sometimes making people feel drowsy, actually disrupts sleep quality and can lead to more nighttime awakenings.

8. Stress and Anxiety

The transition to college can be stressful: moving away from home, adjusting to new academic expectations, managing finances, and navigating social dynamics. Stress hormones like cortisol can make it harder to fall asleep, and worries often feel louder at night when everything is quiet.

The Consequences of Chronic Sleep Disruption

While the occasional late night won’t derail most students, consistently poor sleep can take a toll:

• Weaker academic performance: Sleep is critical for memory consolidation and focus. Sleep-deprived students struggle more with attention, problem-solving, and retaining new information.

• Mood issues: Chronic sleep loss increases the risk of depression, anxiety, and irritability.

• Physical health problems: Poor sleep can weaken the immune system, making students more prone to illness.

• Safety risks: Sleep deprivation slows reaction times, increasing the risk of accidents, especially for students who drive.

How Students Can Protect Their Sleep

While the college environment makes good sleep a challenge, it’s not impossible to maintain healthy habits. Small, consistent changes can make a big difference.

1. Set a consistent sleep and wake schedule. Even if classes start later some days, try to wake up within an hour of your usual time. Get 15-30 minutes of sunlight upon awakening.

2. Create a wind-down routine. Dim lights, read, or listen to calm music 30–60 minutes before bed.

3. Limit caffeine after early afternoon. Switch to water or herbal tea in the evenings.

4. Use screens wisely. Set a “screens off” time before bed or use blue light filters if you must use devices late.

5. Optimize your sleep environment. Earplugs, white noise apps, blackout curtains, and comfortable bedding can counteract noisy or bright dorm conditions.

6. Manage workload earlier in the day. Tackling assignments in the afternoon can free up evenings for relaxation.

7. Communicate with roommates. Agree on quiet hours and be respectful of each other’s rest needs.

The Role of Campus Support

Many colleges now recognize the importance of sleep for student well-being and academic success. Some offer workshops on sleep hygiene, quiet study spaces for daytime work, and counseling services for stress management. Residence hall staff may also help mediate noise issues or support students struggling with adjustment.

The Bottom Line

Being in college disrupts sleep for many reasons — from late-night socializing and irregular schedules to noisy dorms and heavy workloads. While the culture often treats staying up late as a normal part of student life, the reality is that chronic sleep disruption can sap energy, harm academic performance, and affect mental and physical health.

College students who learn to prioritize and protect their sleep gain a significant advantage: more focus, better grades, steadier moods, and greater resilience. In an environment where so much feels new and out of control, sleep is one area where smart habits can make all the difference.

This article was created using OpenAI’s ChatGPT on August 15, 2025 and it was personally reviewed and edited by Brandon Peters, M.D. to ensure its accuracy. This use of augmented intelligence in this way allows the creation of health information that can be trusted.