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.

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.

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.