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Seasonal affective disorder, or SAD, is a form of depression characterized by an uptick in symptoms after periods of seasonal transition. The majority of people diagnosed with SAD experience the highest levels of depressive symptoms during the fall and winter. SAD is strongly linked to natural light exposure. The circadian clock, a biological timekeeper that regulates mood and sleep, relies on natural light to function properly. As a result, people with SAD experience low points when daylight is scarce.
There are several ways to treat SAD, including prescribed medication and cognitive behavioral therapy. However, light therapy (also known as phototherapy) has proven most effective for many people with this disorder. Light therapy involves a device known as a light therapy box, which emits high concentrations of bright, artificial light that can substitute for natural light; when used correctly, light therapy boxes can improve circadian cycles and alleviate symptoms for people with SAD.
This guide will discuss the causes and effects of SAD and benefits of light therapy, as well as buying considerations and light therapy box recommendations. Below you will find our picks for the best light therapy boxes sold today (scroll down to find profiles for each of these devices). Our choices are based on verified customer and owner experiences, as well as intensive product research and analysis.
Seasonal affective disorder, or SAD, is a form of depression that is typically triggered by seasonal changes. Most people with SAD experience the strongest symptoms during the fall and winter months, when natural sunlight declines. In most cases, SAD symptoms will gradually intensify as the triggering seasons progress and taper off once they come to an end – though these symptoms may worsen year after year.
SAD is often linked to sleep disruption. The circadian clock that controls sleep cycles in humans is largely influenced by exposure to sunlight; decreases in natural light that occur during the fall and winter can disrupt circadian rhythm and hinder the production of melatonin, a hormone that regulates feelings of sleepiness and wakefulness.
For these reasons, light therapy can be highly beneficial to people with SAD who experience sleep problems. Light therapy boxes are bedside devices that mimic natural sunlight; most sleepers find that 30 minutes of exposure every morning during darker months can improve their mood and alleviate SAD symptoms.
Read on for more information about how SAD is diagnosed and treated, as well as a detailed description of how light therapy works.
Seasonal affective disorder is considered a type of depression, rather than a distinct mental health disorder. The majority of people with SAD experience the strongest symptoms during fall and winter, though a small contingent experience the symptoms during the spring and summer months.
It is important to note that many people experience mood changes during seasonal transitions. However, according to the National Institute of Mental Health, there is a clear distinction between these common mood changes and SAD. Read on to learn more about causes, risk factors, symptoms, and treatment options.
Though the exact cause(s) of SAD have not been officially recognized, the disorder usually occurs alongside the following factors:
Additionally, medical experts have pinpointed the following risk factors for SAD:
In order to be diagnosed with SAD, individuals must meet the criteria for major depression during distinct seasons for at least two years. These symptoms of major depression include:
Additionally, the NIMH has identified the following symptoms that are specific to fall/winter-onset SAD and spring/summer-onset SAD:
|Fall/Winter-Onset SAD Symptoms||Spring/Summer-Onset SAD Symptoms|
|-Feelings of low energy
-Hypersomnia (excessive sleeping)
-Overeating and weight gain
|-Feelings of agitation, anxiety, and restlessness
-Lack of appetite and weight loss
If untreated, SAD can lead to complications for those who experience symptoms. These may include social withdrawal, problems at school or work, feelings of anxiety, and suicidal thoughts. Early intervention is key.
The diagnostic process for SAD requires a comprehensive evaluation from a physician or mental health professional. This evaluation typically includes:
Based on the outcome of this evaluation, the care provider may administer an SAD diagnosis using criteria from the Diagnostic and Statistical Manual of Mental Disorders (DSM-5). Once this diagnosis has been made, the doctor or mental health professional may give the following treatment recommendations:
While these treatment options may be effective for people with SAD, light therapy has been the primary strategy for treating SAD for decades. Next, we’ll take a closer look at light therapy and discuss how it benefits those with SAD and other health problems and mental health disorders.
Studies have shown that light therapy can significantly improve SAD symptoms — and can be equally as effective as medication. For those looking for alternatives to medication, or just hoping for a straightforward solution, light therapy should be considered a strong contender to treat SAD.
Light therapy usually comes from a box or lamp that emits full-spectrum light similar to sunlight. This light helps emulate the amount of sunlight and full-spectrum rays that are missing during the more dreary seasons like fall and winter. Although many users feel the effect in a matter of days, some people will find it takes two weeks or more to really start feeling an improvement in symptoms and mood.
Use caution if you have bipolar disorder, conditions with skin sensitivity, or a condition that makes your eyes vulnerable to damage. Unlike prescription antidepressants, light therapy doesn’t require a doctor’s prescription, but it can have adverse effects on certain populations.
Additionally, using light therapy isn’t as simple as switching on a lamp and going about your day. There are several best practices that make light therapy more effective. As we’ll go over in the section below, people using a lamp to relieve symptoms of SAD should create a daily routine around using the lamp for the proper amount of time, at the right time of day, and in the optimal proximity.
Every person with SAD is different in terms of ideal light therapy box settings.
The benefits of light therapy are not limited to those with SAD. This form of therapy has proven effective at alleviating symptoms for the following sleep disorders, as well. To read more about these disorders, please click the links found in each section.
|Advanced Sleep-Wake Phase Disorder||This disorder is characterized by early bedtimes and arousal in the middle of the night; it is essentially the polar opposite of delayed sleep-wake phase disorder. Most people with this disorder go to bed between 6pm and 9pm, and will awaken between 2am and 5am. For advanced sleep-wake disorder, using a light therapy box in the evening – rather than the morning – is usually most effective. Read more about Advanced Sleep-Wake Phase Disorder.|
|Irregular Sleep-Wake Rhythm Disorder||Irregular sleep-wake rhythm disorder is characterized by sleep patterns that do not coincide with typical circadian rhythms. People with this disorder frequently nap for long periods during the day and experience deep sleep at abnormal times during the night. Those with irregular sleep-wake rhythm disorder typically find that using a light therapy box in the mornings and avoiding light therapy in the evenings is the best way to correct their irregular sleep patterns. Read more about Irregular Sleep-Wake Rhythm Disorder.|
|Shift Work Sleep Disorder||This condition typically affects people who work late at night and sleep during the day; despite getting eight hours of sleep or more, daytime light exposure can disrupt their circadian processes. Shift work disorder has been linked to poor work performance, mood swings, and a higher risk of being involved in an accident. Regardless of the specific time of day when night workers go to bed and get up, light therapy tends to be most effective when they first wake up; dim light therapy before bedtime may also help. Read more about Shift Work Sleep Disorder.|
|Non-24-Hour Sleep-Wake Disorder||People with non-24-hour sleep-wake disorder follow sleep patterns that do not align with the typical 24-hour day; as a result, they may not feel tired at night and/or wakeful in the morning. Timed light therapy that coincides with normal sleep-wake cycles may be used to correct this disorder. Read more about Non-24-Hour Sleep-Wake Disorder.|
|Jet Lag||People experience jet lag when they travel to different time zones over a relatively short period of time (typically by airplane). The condition causes them to feel tired and wakeful at abnormal times because their bodies have become accustomed to different geographical areas. Jet lag initially manifests immediately after the individual reaches their destination, and will re-manifest after they return home; jet lag may last as little as one or two days up to one week per episode, depending on the distance traveled. Light therapy delivered at normal sleep-wake times for the user's current location can help correct jet lag, though the condition is never permanent (even after long getaways).Read more about Jet Lag.|
Our Editor’s Choice is the Aura Day Light Therapy Lamp, a compact light therapy box loaded with helpful features. The adjustable lux dial allows users to adjust the brightness anywhere from 3,500 to 10,000 lux of white light. The lamp also has a built-in timer that ranges from 10 to 60 minutes; when the countdown is complete, the lamp will automatically shut off – preventing users from overexposure if they lose track of time.
The Aura Day Light Therapy Lamp can be adjusted to 70 or 85 degrees for ideal positioning. It can be mounted on walls, as well. And due to its compact size and light frame (3.4 pounds), it will fit on most bedside surfaces. The lamp is designed with a sophisticated filtration system that prevents UV rays from being emitted.
The Aura Day Light Therapy Lamp is currently available for roughly $100, making it a good option for shoppers with bigger budgets. This product is backed by a two-year warranty.
The HappyLight Deluxe from Verilux is a flexible, effective light therapy box that provides anywhere from 2,500 to 10,000 lux of bright white light using a 36-watt bulb. Users can select a duration anywhere from 10 to 60 minutes, and the device can be adjusted to multiple angles for optimal positioning. It weighs slightly less than 10 pounds and comes with a fold out base for added stability.
The HappyLight Deluxe filters out all UV rays, keeping users safe from harmful exposure. Unlike many other light therapy boxes (which can produce buzzing sounds), this device is also virtually quiet when in use. The product has been tested for eye safety, as well.
The HappyLight Deluxe has a higher-than-average price-point compared to other light therapy boxes; it is currently available for roughly $150. Amazon Prime members qualify for free shipping. Verilux backs the HappyLight Deluxe with a one-year warranty.
The Carex Day-Light Therapy Lamp offers two light settings: a 7,000 lux ‘task lighting’ setting for moderate light therapy using two 36-watt bulbs; and 10,000 lux ‘light therapy’ setting for maximum brightness using three 36-watt bulbs. Its timer is programmable in five-minute increments anywhere from 30 to 60 minutes, making it suitable for most people with SAD and other sleep disorders that can be treated with light exposure.
Mimicking the look of a standard desk lamp, this device can be adjusted for angle and height (25″ to 28″) for optimal positioning. The lamp weighs roughly 9.5 pounds. The Day-Light Therapy Lamp also has a filtration system that blocks more than 99% of UV rays.
The Carex Day-Light Therapy Lamp is widely sold for $110 or less. The product is backed by a five-year warranty, which is much longer than average compared to the warranties of other light therapy devices.
Our Best Value pick is the NatureBright SunTouch Plus Light, a light therapy box that is widely available for $40. However, this device offers the same effective light therapy as many competing models with higher price-points. The SunTouch Plus Light emits the recommended 10,000 lux of bright white light for people with SAD. Its timer is programmable for 15-, 30-, 45-, and 60-minute durations, as well.
Additionally, this device has a built-in negative ionizer. Negative ions are odorless particles that form naturally in the air; they are most prominent in natural surroundings and after rainfall, and have been linked to improved moods. The SunTouch Plus Light also filters out most UV rays. The device has received recommendations from the Columbia Department of Psychiatry and the New York State Psychiatry Institute.
Amazon Prime members qualify for free shipping when they order the NatureBright SunTouch Plus Light. This device is backed by a one-year warranty.
When shopping for a new light therapy box and comparing different brands and models, here are a few important factors to take into account:
Also known as full spectrum fluorescent lighting (FSFL), this product is marketed as the more “natural” alternative to traditional SAD lamps. Natural spectrum lights are made to emulate the full electromagnetic spectrum of light. These lamps can come in many forms, finishes, sizes, wattages, and voltages.
In the early 2000’s, many companies made scientific claims that FSFLs were able to treat Seasonal Affective Disorder, slow aging of the retina, and even reduce the chance of skin cancer. Unfortunately, it appears that full spectrum lights are not all they’re cracked up to be, and so far have no real support or rooting in science.
One study conducted over a 50 year period found that this type of full-spectrum lighting hasn’t shown any dramatic effects on human behavior or health. So far, other studies have shown that it takes a light emission of at least 1000 lux to treat Seasonal Affective Disorder.
However, the natural spectrum light bulbs currently on the market don’t have this same level of powerful emission. Their pleasant light may allow the user to experience better visual acuity or less tiredness, but those effects are not enough to effectively treat SAD.
Unlike a regular SAD lamp that is turned on for a short period of time during the day, dawn simulators can help you wake gently from your sleep. This acts as a sort of planned alarm clock, but the gradual increase of light, instead of noise, wakes you from your slumber. Most also have a sunsetting feature that allows you to fall asleep to a gradual light decrease.
Dawn simulators, sometimes known as “wake up lights”, have shown many benefits in their own right. These devices may allow you to sleep better and wake up more naturally in the morning. Because one symptom of SAD is difficulty sleeping, people have shown positive clinical responses to dawn simulators. However, in terms of treating SAD, dawn simulators have more mixed results.
That’s because the benefits they offer are somewhat differentiated from clinically-approved SAD usage. SAD lamps are still the most effective treatment for seasonal affective disorder. For best possible usage, you can choose to combine the two: waking up to a dawn simulator and using a SAD lamp treatment about half an hour later has been shown as the most effective SAD treatment.
Blue light has the highest amount of energy in the visible light spectrum. While blue light has traditionally come from the sun, we now consume it all the time in the form of electronics: think computers, smartphones, tablets, and TVs.
Traditional SAD lamps use bright white-light treatment instead of narrow-band blue-light treatment. However, multiple studies have found that the use of blue light treatment is equally effective in treatment for SAD as white light. Blue light to treat SAD is administered through a light-emitting diode (LED) lamp that emits narrow-spectrum blue light.
Of course, this shouldn’t be mixed up with the wrong kinds of blue light exposure right before bed. Exposure to blue light late at night suppresses the secretion of melatonin, which may influence your circadian rhythms and overall ability to sleep. Said in another way: make sure you’re getting the right kind of blue light earlier in the day, and not later.
Red lights have the longest wavelength on the light spectrum. Red light therapy has all kinds of different names, such as:
Red light’s efficacy in a wide variety of applications (including treating SAD) has often been inconclusive. When compared to other 10,000 lux visible-spectrum studies, blue-light therapy proved superior to red-light therapy. In fact, even green light therapy has been found more effective than red light for this purpose. That’s because red light is not as successful in mediating photoreceptors in the eye that promote an antidepressant response.
Red light has gone through many studies in scientific vogue, from treatment for skin problems to helping grow plants in space. Some studies suggest that red light therapy may help promote skin healing, prevent recurring cold sores, relieve pain and inflammation, and even help with stiffness associated with rheumatoid arthritis. But for now, it’s best to take these hypotheses with a grain of salt, as findings remain inconclusive.
Overall, even though red light may seem interesting in helping with SAD, blue light and white light therapy have been proven equally more effective.
Light boxes are the best way for you to receive light therapy for SAD. Below, we’ll lead you through the best light boxes and why they work so well.
Looking for a more solid understanding on light, seasonal affective disorder, and topics like your circadian rhythm? Understanding these subjects more deeply will allow you to find the right products for you and help you achieve a better night’s sleep.