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Seasonal Affective Disorder

Counseling and Psychological Services has a limited number of Verilux HappyLight Energy Lamps for student checkout (please contact CAPS for current availability). If you've already checked one of these lamps out, please access the following documents for instructions regarding use, and read below for more information about Seasonal Affective Disorder.

Verilux Instructions   Using Light Therapy   Winter Blues SAD Handout

Now that Daylight Savings Time is over, most of us go to work and return home in darkness. And for some people, the loss of light causes their moods to dim as well.

The Academy of Family Practice explains that 10% of the U.S. population may suffer from winter depression (Seasonal Affective Disorder or SAD). And as many as 25% feel the "winter blahs," a condition of less severity, but with many of SAD's symptoms. Think of a scale from 1 to 10.  At 1 - 4, a person may feel blue, having lost the joy he or she normally experiences. From 5 - 8, the person is likely in full-blown SAD. At 9 - 10, a crisis may occur; people can become so depressed they consider suicide.

People are sometimes surprised when they reflect on past years and recognize their moods have darkened as winter has approached.

Seasonal Affective Disorder is caused, not by the cold, but by diminished light. The problem is worse in northern latitudes where days are shorter. For example, in Florida only about 1.5% of people have SAD. In Washington State, it is 7 times higher, beginning around October and ending about April. In Spokane, during the months between November and March the majority of the days are cloudy, thus compounding the problem.

Symptoms of SAD include: Depression beginning in the autumn and remitting in the spring, heavier alcohol use to "self-medicate," craving junk food and soft drinks, increased need for sleep, difficulty concentrating, carbohydrate cravings, decreased sex drive, decreased energy, suicidal thoughts, social isolation, weight gain, listlessness, loss of joy, pessimism, irritability, sadness, and fatigue.

Why do people get SAD? The answer is not known exactly, but researchers believe lack of sunlight affects the body's chemistry. With shorter days, melatonin (the "hormone of darkness") is secreted in higher levels, resulting in a disturbance of the body's natural rhythms. Declining light also decreases serotonin ("the happiness hormone"). It may be that the body's inability to produce Vitamin D, (the "sunshine vitamin") in the winter causes mood to plummet. SAD may be the result of any or all of these situations.

Dr. Norman Rosenthal, Clinical Professor of Psychiatry at Georgetown Medical School, has researched SAD for 25 years. He says, "For some people, it seems as if they have two different personalities. The summer person is energetic, cheerful and productive. But the winter person has little energy and finds it difficult to cope with every day tasks. As days grow longer again in March to April, the energetic person reappears."

If lack of light is the cause of winter depression, then it makes sense that adding more light can be therapeutic. Rosenthal has found this to be true. Research shows that increasing light can help with SAD. In fact, light therapy, or phototherapy, is as effective as taking an anti-depressant medication, and may help more quickly and with fewer side effects. Rosenthal says, "Although it varies from person to person, most feel effects of light therapy in 2 to 4 days." He adds, "Don't give up on light until you have used it consistently for several weeks." As time passes, 80 - 95% of people can continue their journeys to a normal mood state, even on dark, cold days.

But not just any light will do. Most studies have shown that depressive symptoms can be lifted by exposure to a particular type of bulb that provides intense light. Recommended treatment is to sit next to a special fluorescent light that provides 10,000 lux (a unit of measuring the light's intensity).

To get a feeling for light intensity, a typical living room might have lighting at 50 lux. A business office might have about 320 -500 lux. On a December day in Spokane there may be 1000 lux. In direct sunlight on a summer day, there would be greater than 100,000 lux.

SAD lamps have filters to remove damaging UV rays. Rosenthal suggests starting with 15 to 20 minutes a day, and to work up to about 30 minutes. Place the lamp at a distance of about 12 - 15 inches from the face, with the light shining from above. The light should pass in front of the face; don't stare into the light. People often use these lights at the breakfast table, to apply makeup, or on the desk next to the computer.

Most people need the light first thing in the morning. These lamps come in several styles: as desk lamps, floor lamps, light boxes, and even as bulbs embedded in visors so that a person can move around and take the light with them.

There can be negative effects from using light therapy. Some people experience headaches, insomnia or dry eyes. It might require an adjustment of the time spent with the light, or with the distance from the lamp, to obtain alleviation of depressive symptoms. Discuss using light therapy with a medical professional if you have bipolar disorder. In some studies, patients undergoing light treatment have become manic as a result. Check with your medical provider if you are taking any medications that react poorly to bright light (certain antibiotics or anti-inflammatories).

The lights can be expensive (between $180.00 to $300.00), but the lamps are generally used beginning about October and ending when daylight lengthens in the spring. The lamps can then be put away until the next fall. The bulbs have 1000s of hours of light capacity and will likely last for years.

David Avery, MD, psychiatrist at The University of Washington, has done research with dawn simulators. This is also light therapy, but delivered in a different way. Dawn simulators are set to gradually fill the bedroom with light, approximately 90 minutes prior to the normal waking time, thus imitating a natural sunrise. This light gently tells the body it is time to awaken - even if it is still dark outside. Avery explains, "We think the light signal through the eyelids connects to the hypothalamus in the brain and in essence resets the body's clock."

Dr. Rosenthal suggests, "It is best to start light therapy as soon as the first symptoms of winter depression appear, before they progress to a full-blown picture of SAD." Use of a SAD light must be consistent. Once the symptoms of depression have diminished, regular use of the lamp will likely be needed until springtime when sunlight increases.

SAD lights are available from several companies online, including the following (Please note that this is not an endorsement, but meant simply to assist the search for SAD resources):  / / / / /

What Else Can You Do? There may be a number of things that help.

  • Go outdoors and walk briskly if we do have a sunny day. Remember - don't wear sunglasses. Or work out in a brightly lit gym. Exercising increases the body's endorphins ("natural morphine") and fights depression. Look forward to an outdoor activity such as ice skating, skiing or sledding.
  • Open blinds and curtains and turn on lamps during the day in your home or office.
  • Eat foods high in Omega-3 fatty acids. Examples are wild salmon, flaxseed oil, walnuts, oysters, sardines, beans, olive oil, soy products and halibut. Fish oil supplements are inexpensive and easy to take.
  • Avery emphasizes good sleep habits. Try to go to bed and arise on a regular schedule. Make the bedroom completely dark and cool. Dim the lights in the evening, signaling the brain the day is winding down.
  • Start a gratitude list. Even simple things that can be appreciated - a good cup of coffee, a call from a friend, a new experience, the love for your pet. Focusing on the positive gives a perspective that reduces depression.
  • Do something for someone else. Give an anonymous gift. Give your time to a good cause.
  • Don't go into hibernation mode. Continue making and accepting social connections. Schedule fun activities.
  • Schedule a winter vacation to a sunny place.
  • Increase your Vitamin D intake. Recent studies show that vitamin D protects against depression, osteoporosis, heart disease, multiple sclerosis, rheumatoid arthritis, infections and cancers. Good sources of vitamin D are fortified milk, salmon, tuna and eggs. A lab test can measure vitamin D levels and then the proper dosage can be prescribed.
  • Talk to a mental health provider. Psychologists have found that the use of good therapy, particularly Cognitive Behavioral Therapy (CBT) can be very helpful for depression.
  • If depression isn't alleviated with these suggestions, visit with a medical professional to discuss medication. The FDA recommendation for SAD is Buproprion XL or one of the drugs in the SSRI class such as Prozac or Zoloft.

Once a person recognizes the pattern of SAD, it can be a relief to know there is help. Checking with a medical practitioner prior to beginning the above treatments can be important. And if symptoms become intolerable, don't wait to call for help.

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