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Article Image: "See The Light Through Seasonal Affective Disorder"

See The Light Through Seasonal Affective Disorder

It’s that time of the year again.

The leaves are falling. The temperatures are dipping. The days are becoming shorter. While some people revel in these telltale signs of winter, others find their positive moods slipping away from them without explanation. What’s one possible culprit? A depressive condition called winter Seasonal Affective Disorder, commonly known as winter depression, the winter blues, and more simply, SAD.

Affecting nearly half a million people in the United States, winter SAD is a mood disorder in which people who have generally positive mental health most of the year experience mild to severe depression in the fall and winter seasons. Although researchers are not clear about the exact causes of winter SAD, they think it may be linked to a lack of sunlight. Researchers believe that too little sunlight can affect a person’s body negatively in 3 ways:

  • It disrupts the body’s circadian rhythm. – The body’s circadian rhythm is commonly referred to as its “biological clock,” or 24-hour cycle. It controls physiological functions such as sleeping and waking, body temperature regulation, the balance of bodily fluids, and the manner in which other body systems function. A lack of sunlight upsets this cycle and can trigger feelings of lethargy, fatigue, and depression.
  • It decreases the brain’s level of serotonin. – Serotonin is a neurotransmitter that influences a range of the body’s psychological functions, including mood. A lack of sunlight can cause a drop in the brain’s serotonin supply, possibly leading to depressive symptoms.
  • It increases the body’s supply of melatonin. – Melatonin is a hormone that helps regulate the body’s sleep and wake cycles. Usually, the body’s melatonin levels rise in mid- to late evening, remain high for most of the night, and decline in the early morning hours. Melatonin production is partially affected by the amount of sunlight present. Therefore, during the shorter days of winter, the body may produce melatonin earlier, more often, or later. These changes can lead to winter SAD.

According to the Mayo Clinic, winter SAD is more common among people who live at high latitudes in locations that are farther north or south of the equator. In these areas, seasonal changes are typically more extreme. As an example, almost 10% of Alaska residents are afflicted with SAD, while only about 1% of Florida residents suffer from the disorder.

Although a genetic link has not been discovered, SAD is most common in people who have family members who suffer or have suffered from the condition in the past. Other notable at-risk groups include women, who are diagnosed with SAD more often than men, and people between the ages of 15 and 55. Although men are less often affected by the disorder, researchers have found that those men who do suffer from SAD have more severe symptoms.


Symptoms of Winter SAD

The symptoms of winter SAD are similar to those of depression. According to WebMD, a person with SAD might:

  • Sleep more and feel drowsy during the day
  • Feel sad, hopeless, moody, grumpy, and/or anxious
  • Lose interest in his or her usual activities
  • Gain weight
  • Crave food that is high in carbohydrates

In addition, a person may experience a loss of energy, have difficulty concentrating, and withdraw from social situations. These symptoms usually begin in late fall and last until springtime or, in some cases, summer. People with winter-onset SAD have usually felt depressed during the fall and winter and have gotten better when the seasons changed for 2 years in a row.


Treating SAD

Although antidepressant medications and psychotherapy are helpful treatments for winter SAD, doctors most often prescribe light therapy to combat the disorder. Light therapy involves the use of high-intensity fluorescent lamps – full spectrum lights – to mimic the presence of natural, outdoor light and initiate a biochemical change in the brain meant to lift a person’s mood. Full spectrum lights have light intensities measuring 10,000 lux, which is roughly 10 to 20 times as bright as ordinary indoor lighting. Their internal components consist of white fluorescent light tubes covered with plastic screens that block ultraviolet rays.

There are 2 basic types of light therapy, also known as phototherapy:

  • Bright Light Therapy - During bright light treatment, a person sits a few feet from a full spectrum light or SAD light box for at least 30 minutes once or twice a day. Studies have demonstrated that morning light therapy is more effective than conducting evening treatments, which may trigger insomnia.
  • Dawn Simulation – During dawn simulation, a dim light comes on and brightens gradually over a period of 30 minutes to 2 hours before a person wakes up, simulating the sunrise. Dawn simulator lights give off less intense light at 200 to 300 lux when compared to full spectrum lights. SAD-sufferers might find this type of treatment to be more convenient than conducting bright light therapy after they wake up.

Both types of light therapy treatment are equally effective, and they can be combined to maximize the recovery process. After beginning light therapy, it takes approximately 2 to 4 days to see an improvement in symptoms and about 2 to 4 weeks to reach recovery.


Full Spectrum Lighting offers a collection of SAD light boxes and full spectrum lights. They come in a variety of designs, sizes, and brightness levels. Moreover, SAD-sufferers can choose a light rated for mild, moderate, or severe symptoms to suit their particular needs. Verilux lights include attractive, modern-style floor and desk lamps as well as large surface sunshine simulator lights that are highly effective mood enhancers. The Verilux Happylite Deluxe Sunshine Simulator produces instant flicker-free natural light that helps increase energy and stimulate positive thinking.

Apollo lights, manufactured by Philips Home Healthcare Solutions (formerly Apollo Health), are continually tested and proven to be effective solutions for the treatment of SAD through the company’s partnership with the National Institute of Health. The Apollo BriteLite 6 provides faster treatment than a traditional SAD lightbox because it shines 50% more of the most effective light wavelengths for treating SAD. The Apollo goLITE is considered even more effective because it uses BLUEWAVE technology, a specific bandwidth of light that can suppress melatonin levels.


Added Benefits

Along with helping to relieve symptoms of winter-onset SAD, full spectrum lights have also been proven to relieve eyestrain, improve light contrast, and help portray true colors. This is highly beneficial when reading, working on art or craft projects, sewing, or doing any other type of work that requires elevated attention to detail. The Verilux Heritage Deluxe Desk Lamp features flicker-free technology and uses a glare-control filter that eliminates any reflective or peripheral light glare, a common cause of eyestrain and headaches. As another benefit, many full spectrum lights use energy-efficient bulbs with exceptionally longer lives than traditional light bulbs. This helps save on energy costs and is kinder to the environment.


Still Got Questions?

For more information on specific products and ways to improve your indoor environment, review our extensive product listings and other educational materials. Not sure what's best for you? We can take the guess work out of decision-making. Contact our product experts toll free at 1 (800) 934-9194 for a detailed consultation. Our goal is to make your indoor environment healthy and comfortable.

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