Let there be light! Or not… depending upon what you need.
Circadian rhythm disorders can complicate one’s life drastically. The most common ones are things you’ve probably heard of:
- Seasonal Affective Disorder: A mood disorder related to reduced exposure to sunlight that can have a tremendous impact on sleep
- Jet Lag: A temporary disruption of one’s circadian rhythms
- Shift Work Disorder: The negative whole-body impact of working evening and overnight shifts on one’s circadian rhythms
And then there are these less common, though potentially devastating disorders and situations:
- Irregular Sleep-Wake Rhythm: When one’s circadian rhythms have no recognizable pattern
- Non-24 Sleep-Wake Disorder: When one’s circadian rhythms continuously shift so that sleep-wake cycles are always changing
- Delayed Sleep Phase Disorder: When one’s circadian rhythms tend to run far later than is ordinary, which can complicate daily living
- Advanced Sleep Phase Disorder: When one’s circadian rhythms tend to run far earlier than is ordinary, which can complicate daily living
- Social Jet Lag: Otherwise known as the Monday Morning Blues, the temporary circadian disruption that follows a weekend of distinctively different sleep patterns, leading to significant struggles in waking up at the beginning of the work week
Because our circadian systems depend primarily (though not completely) on light to achieve a healthy balance, different kinds of light therapy are used to help entrain or reset our rhythms so that we can better achieve a normal day-to-day schedule. (Learn more about circadian rhythm disorders and how they can be extremely disabling here and here.)
Light can be used in multiple applications to help reset your rhythms, as well as to improve your alertness during the day or encourage melatonin release at bedtime. Typically it involves exposure to certain colors of light along the light spectrum following a plan based on time of day and duration.
Most light therapy applications are employed in the morning to signal alertness and relieve Seasonal Affective Disorder (SAD), but light exposure strategies for people with shift work disorder, jet lag, and insomnia require more careful timing of certain kinds of light exposure and, sometimes, avoidance of blue spectrum light.
Please be advised that NOT EVERYBODY can use light therapy. For instance, people with bipolar disorder should not use it as it may actually lead to manic episodes. If you are unsure whether it is appropriate and/or safe for you or a loved one, please discuss your concerns with a medical professional.
Below, SHC shares different applications for using light therapy (also known as phototherapy or heliotherapy) for specific kinds of circadian rhythm disorders. As with any medical device, it is recommended you review the manufacturer’s directions first before using, especially the section on personal safety.
SHC cannot be held responsible for the misuse or abuse of any device or therapy
discussed in any of these links; this curation of links is for educational purposes only.
Products included in these linked discussions are not necessarily endorsed by SHC.
Seasonal Affective Disorder
MAR 14: Mosaic, The Science of Life
Is the dark really making me sad?
From the article: “Of course, the idea of using light to counter the winter blues is nothing new. SAD lamps are a mainstay of treatment for winter depression, and in Sweden, which was a vigorous early adopter of light therapy, clinics often went one step further: dressing patients in all-white clothes and sending them into white rooms filled with bright light.”
JAN 11: Medical Daily
5 Myths And Facts About Light Therapy: This Bright Treatment’s Effect On Your Brain
From the article: “Light therapy is not to be taken lightly—it’s a treatment that has improved the lives of many people. … But there are many misconceptions about light therapy.”
OCT 11, 2016: Romper
Can Kids Get Seasonal Affective Disorder?
From the article: “Sufferers of SAD are encouraged to be outside in natural daylight for as long as possible every day.”
MAY 26, 2014: Center for Environmental Therapeutics
Q: Can you tell me if someone who has had one of the following treatments, and was advised not to be exposed to sunlight, might still undergo light therapy?
From the advice column: “When doctors advise patients to avoid sunlight, the risk factor is almost always ultraviolet (UV) radiation. …an adequate light box should screen out UV, in which case there should be no UV risk.”
MAY 26, 2014: Center for Environmental Therapeutics
Q: [C]an I assume that it is safe to continue my use CET’s recommended light box, 30 minutes a day in the morning, during the summer months?
From the advice column: “Patients with non-seasonal depression, or depression that lifts somewhat but incompletely in summer, are now using light therapy throughout the year. This is unnecessary (and not recommended) for those with ‘simple SAD’ who are asymptomatic in late spring and throughout the summer.”
2014: Center for Environmental Therapeutics
Circadian Rhythm and Blues: An Interview with Michael Terman, PhD
From the website: “Light therapy can often alleviate both major depression and winter blues (seasonal affective disorder, or SAD).”
OCT 8, 2012: ShareCare
Q: How can light therapy affect mood in seniors?
From the advice column: “A recent study of 89 depressed patients over the age of 60 years were split into two groups: one group was given one hour of either 7,500-lux bright pale-blue light therapy in the morning or dim red light as a control.” [See also our recent discussion on seniors and circadian rhythm disorders.]
EXTRA! EXTRA! Did you know…?
JAN 14, 2015: Psychology Today
Reverse Seasonal Affective Disorder: SAD in the Summer
From the article: “Reverse seasonal affective disorder affects less than 1/10th of all [Seasonal Affective Disorder] SAD cases, according to the National Alliance on Mental Illness. But just like winter-onset SAD, reverse seasonal affective disorder returns every year at about the same time.”
Shift Work Disorder
MAR 31: Sleep Resolutions
How to Treat Shift Work Sleep Disorder
From the website: “If you work a job with hours that fall outside the traditional 9 to 5 work day — for example, an overnight shift/graveyard shift, a double shift, or if your schedule rotates often — you may find yourself struggling with excessive daytime sleepiness or insomnia. If your problems sleeping or feeling rested are persistent or even daily, you may have what’s called shift work sleep disorder. ” [See also our recent discussion on shift work disorder as an occupational hazard.]
MAR 5: Brantford Expositor
Coping with Shift Work
From the website: “HumanCharger, an innovative light therapy device, uses a unique and patented mechanism of action, which stimulates the photosensitive receptors on the surface of the brain. This device uses a calibrated white light, instead of the common blue light, that passes through the ear canals and helps release specific proteins. ” [See also our recent discussion on wearable technology for sleep.]
EXTRA! EXTRA! Did you know…?
OCT 20, 2016: The Atlantic
How Night Shifts Perpetuate Health Inequality
From the article: “The International Agency for Research on Cancer has listed night shifts as “probably carcinogenic.”
MAR 8: Urban Mommies
Combatting Jetlag in Kinds
From the blog: “JET LAG. Do you know what’s worse? KIDS with JET LAG. I know. They’re like a cross between Gremlins and heavy rocks. Here are 7 ideas to combat jetlag in kids so the gremlin thing doesn’t happen.” This post was sponsored by Philips.
FEB 28: In the Know
This gadget helps reduce jet lag by retiming your internal body clock (YouTube video)
From the video: “This portable device helps you to reduce jet lag.” Luminette is a similar device.
NOV 23, 2016: Sleep Review
Editor’s Message: Catching Up to Jet Lag (YouTube video)
From the commentary: “A study by Stanford University School of Medicine found that exposing people to short flashes of light while they’re sleeping could provide a fast, efficient method of preventing jet lag. ‘This could be a new way of adjusting much more quickly to time changes than other methods in use today,’ said Jamie Zeitzer, PhD, in a release.”
SEP 28, 2016: Medical Daily
Blue Light And Sleep Cycle: How To Limit LED Lighting From Electronic Devices For Melatonin Production
From the article: “Blue light emission at night manipulates the production of sleep hormone melatonin, leading the brain to believe it’s daylight, or time for wakefulness…So, how do we ‘turn off’ blue light for a good night’s sleep?” [See also our discussion on using reading lights at bedtime.]
AUG 23, 2016: Medical Daily
6 Science-Backed Cures For Insomnia
From the article: “A 2014 study published in the Journal of Clinical Sleep Medicine found office workers who got more natural light exposure slept about 46 minutes longer per night than their colleagues without windows.” [See also our discussion on using light therapy for various sleep problems.]
For a Basic Circadian Reset
Sometimes you don’t need to have disordered sleep to know your rhythms are simply off and need a reset. Learn more about how your interactions with different kinds of light can help put you back on track.
FEB 8: Reader’s Digest
10 Ways to Naturally Reset Your Sleep Cycle
From the article: “Whether you’re traveling or trying to wake up early to start a new fitness routine, your sleep cycle can get thrown off. Here’s exactly how to adjust to a new sleep rhythm. It’s easier than you’d think.”
JAN 5: Bustle
This Weird Sunglasses Hack Might Help You Sleep Better At Night
From the article: “I tend to associate wearing sunglasses at night with celebrities who think they are too cool for school (or, you know, the normal light levels experienced by us plebeians), but could they be on the right track after all?”
JUN 21, 2016: LifeHacker
Everything You Need to Know About How Light Affects Your Sleep
From the article: “Daylight is the key to keeping rhythms in check. ‘Every day when you get up, you are resetting the biological clock,’ explains Mariana G. Figueiro, program director at Rensselaer Polytechnic Institute’s Lighting Research Center.”
MAR 13, 2014: Only Human/National Geographic
How Light Wakes Up the Brain
From the blog: [N]euroscientists had just discovered a third class of light-sensitive eye cells, called, rather uncreatively, ‘intrinsically photosensitive retinal ganglion cells’ (ipRGCs). These cells have nothing to do with vision. They absorb light in order to properly set our circadian clock.”
OF SPECIAL INTEREST…
JAN 31: Tech Featured
Sleep Disorders in Blind People
From the article: “Did you know that 8 out of 10 blind people suffer from some kind of sleep disorder? … It’s true. Totally blind people (those who cannot perceive light), and many other groups of vision impaired people such as those with achromotopsia (complete color-blindness) and photophobia (extreme light sensitivity) often experience problems falling or staying asleep.”