We wake up, and it's barely light. We come home from work, and it's already dark. It must be November. As if it isn't bad enough that the...

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We wake up, and it’s barely light. We come home from work, and it’s already dark.

It must be November.

As if it isn’t bad enough that the air is chilly and the skies are cloudy, some of us feel cranky, too. Cranky and sluggish and glum, and we’ve got a colossal case of the munchies.

For those most sensitive to weather change, the dimmer days of fall and winter often lead to a type of depression known as Seasonal Affective Disorder (SAD).

About 10 percent of the population in Seattle experiences it each winter. And another 10 to 20 percent have a milder form of SAD, says David Avery, a professor at the University of Washington School of Medicine and director of Inpatient Psychiatry at Harborview Medical Center. He has been studying SAD for 15 years.

SAD looks a lot like clinical depression. Except that it settles in around October and vanishes in the spring.

Where to buy a light box


Indoor Sun Shoppe: 160 N. Canal St., Seattle, 206-634-3727; www.indoorsun.com.

An array of light-therapy products.

Group Health Take Care stores: 2700 152nd Ave. N.E., Redmond (at Group Health hospital), 425-883-5052; 9800 Fourth Ave. N.E. (in Group Health clinic), Seattle, 206-302-1208; 125 16th Ave. E., Seattle, 206-326-3496; 700 Lilly Road N.E., Olympia, 360-923-7678.

A few in-store samples. Order lights from the stores.

www.apollolight.com

www.lighttherapyproducts.com

www.sunbox.com

If your doctor diagnoses you with SAD, she’s likely to suggest you get some sunshine. You can make a point of getting outside for 30 minutes during daylight every day, or you can bask for about half an hour each morning in the rays of a light box. Either way, light therapy has proved helpful to the majority of SAD sufferers, says Maurice Warner, assistant director of the counseling center at the University of Washington.

If a daily sunlight bath isn’t the cards, how does one go about buying a light box? The array of products available is enough to provoke a long winter’s dither.

There are floor lamps, “notebooks” that resemble laptops, nerdy-looking visors that shine artificial light into the eyes. There are Web sites claiming that the wavelength in blue light is the wavelength you need, and ads urging you to buy “full-spectrum” lights. There are dawn simulators that gradually brighten to wake you in the morning and promise to reset your circadian rhythms. There’s also the attaché-case-shaped box, which clearly was designed for function, not beauty. And the prices! You can spend more than $500 on one of these things.

Where do you begin?

SAD symptoms


The onset of seasonal affective disorder (SAD) usually is during autumn months. Its effects, many of which are similar to clinical depression, subside by springtime. Symptoms can include:

• Tiredness

• Loss of interest in normal activities

• Pessimistic mood

• Irritability

• Desire to isolate oneself

• Craving for carbohydrates

• Trouble getting out of bed or other sleep disturbances

• In the worst cases, people might have difficulty following through on life engagements, such as going to work regularly, or even develop suicidal thoughts.

Source: Maurice Warner, assistant director of the counseling center at the University of Washington

Intensity is the key to light boxes, which have about 20 years of research backing their efficacy. The first studies were conducted at the National Institute of Mental Health in the early ’80s.

Look for a box that provides 10,000 lux, a measure of light intensity.

“On a cloudy day in Seattle, the light intensity ranges from 1,000 to 10,000 lux. Being indoors markedly reduces the amount of light you get. A very bright office, for instance, only averages about 500 lux,” says Avery.

There are several competing theories about how light boxes work. The most widely accepted says, “The light moderates our biological clock and affects production of certain neurochemicals in the brain,” says Warner.

“The morning light is what synchronizes our body clocks, which tend to drift … in the absence of light,” says Avery.

What happens when a person vulnerable to SAD stops getting enough light? The body’s system gets desynchronized, Avery says. Supplying that light, even artificially, resets the natural body rhythm, says Warner.

Three factors influence how well a light box works:

• The intensity of the light.

• The length of time you must be exposed to the light.

• How close you must be to the light source.

Know that the box won’t work if you sit across the room from it. Pay attention to the instructions that come with it, and read them before you buy.

The light you purchase is going to become part of your life, so look for one that will allow you to run through some of your morning rituals, reading the newspaper while sipping coffee and eating your Rice Krispies, for example.

You’ll want to buy a light box large enough to provide 10,000 lux at a comfortable distance. Distances typically range from 14 to 24 inches. Generally, the smaller — or less expensive — the box, the closer you must be to get an effective dose of light.

Avery ties a string to the top of light boxes used by subjects in his study. He has them pull the premeasured string to their foreheads to make sure they are close enough. You might want to try something like this when you’re considering whether to buy a particular light box. If the light is supposed to be effective at 14 inches, try positioning yourself within 14 inches of a light source at home for 30 minutes to see whether this will work for you.

A few other tips:

• Try to buy from a company that offers a trial period of two weeks to a month. Then you’ll be able to return the product for a full refund if it doesn’t work for you.

• Ask whether the store carries bulbs so they’re easy to find when yours burn out.

• Shop for comfort. Some boxes emit a great deal of glare.

• Look for a warranty that covers the product and the bulbs.

• The frugal among us might be tempted to buy a second-hand light box. You can find light boxes second-hand (check this newspaper’s classifieds, or eBay or craigslist), but be aware that you might have to replace the bulbs and do without a warranty, and you probably won’t get a refund if you find that the product doesn’t address your symptoms.

Purchased new, light boxes range from $170 to $575, according to a brief survey of area stores and several online distributors.

Only some insurance carriers will pay for light therapy. Group Health does not. Neither does Regence Blue Shield. Premera Blue Cross covers light boxes for patients who are seeing a doctor and undergoing treatment. But the percentage it covers depends on the individual plan.

Use it right

You won’t be sleeping in front of a light box.

It’s a myth that absorbing light through the skin is helpful, says Warner. And even though our eyelids are translucent, meaning light does pass through them, you must keep your eyes open while using a light box. It’s the amount of light entering your eyes that’s critical, he says, adding that you don’t need to look directly into the box.

“Always use the light box in the morning, soon after awakening,” says Avery. Do so for 30 minutes each day.

How will you know it’s working?

“Most folks start to respond within a week. They feel better after two weeks,” Avery says. If someone’s mood is going to be elevated by light therapy, it should take place within three weeks.

Cautions

Light boxes aren’t the answer for everyone.

If you’ve had any damage to your eyes; illness related to vision; or a medical history other than corrective lenses, such as glaucoma or macular degeneration, check with your ophthalmologist before using a light box, experts say.

Temporary headaches can sometimes be a side effect of light-box use.

“Because people have different sensibilities, it’s not going to work for everybody,” Warner says of light therapy. “Students have said it’s changed their life, and we’ve had other students who say, ‘I’ve used it consistently and nothing has changed.’ “

Though light boxes can be purchased without a prescription, Avery urges anyone who believes he might have SAD to seek the help of a therapist, whether it’s a psychologist, psychiatrist or other mental-health professional.

“It may not be an adequate response for the particular kind of depression you’re experiencing,” Warner says. “The biggest problem with using a light box for SAD [is that] people try to use it for concerns that are not SAD; they’re other forms of depression.”

If using a light box does alleviate your symptoms, be consistent. “The effect is short-lived,” says Warner. “You do have to use it every day.”

For now, light boxes are considered one of the best methods of combating SAD. Avery’s research has shown that dawn simulators, which mimic the effect of the sun during summer, can also work well.

Don’t forget, there’s that cost-free alternative: Get outside. Go for a 30-minute walk during lunch, Warner says.

“Light is nature’s way of synchronizing our behavior,” says Avery. “And it has for millions of years, because even one-celled organisms respond to light.”

Judy Chia Hui Hsu: 206-464-3315 or jhsu@seattletimes.com