By Sherry Stripling, Seattle Times staff reporter

HAPPY WINTER SOLSTICE. This weekend is the darkest the dark days of winter, in a region that shares poster-child status with Scotland for Seasonal Affective Disorder. It's what travel books mean when they say about Seattle: "Overcast days and long winter nights have long made the city a haven for moviegoers and book readers." Well, fine. We live here; we have to deal with it. So today we tell you how you can make the darkness a little less overwhelming.

WHAT IS THIS, CANADA?
Our marine climate saves us from deep snow, but, baby, it's dark outside. We get about 75 days a year that aren't cloudy or at least partly cloudy. Until Anchorage took our crown, Seattle was Miss Northern-Most Latitude among major cities in the United States. We get 16 hours of daylight on June 21 but a measly, miserable 8.5 in winter. As they say in London — which has just a few latitudinal degrees on us — we feel like pit ponies toiling in mines as we go to work in the dark and come home in it, too.

	Earth's rotation

WHY IS THERE SO LITTLE LIGHT?
The Earth tilts as it orbits the sun. That's great in the good old summertime: The Northern Hemisphere tilts toward the sun and light rays strike at an angle of about 90 degrees to give us more heat and longer hours of daylight. But in the winter, the Northern Hemisphere tilts away from the sun. The rays hit the Earth at a slant, which spreads the rays over a wider area, dims the lights and sends surfers to Australia.
 

Clifford Mass Where to find sunshine in a hurry? Sequim and environs in the Olympic rain shadow are often good bets for fair weather, suggests Cliff Mass, professor in the University of Washington's Department of Atmospheric Sciences. That area is described by pilots as being home to the "blue hole." "It's there on dozens of days each year, even when it is pouring on the other side of the Olympics and over Seattle," Mass said. "Another good place is along the eastern foothills of the Cascades from Cle Elum through Winthrop."

WHAT HAPPENS WHEN WE DON'T SEE LIGHT?
We run down like solar-powered batteries, which is why January and February are often worse for people even though the days are actually getting longer. People in Seattle are seven times more likely than people in Florida to get Seasonal Affective Disorder, which can be disabling. At least a quarter of us admit to a milder form of winter blues. When days are dark and shorter, the production of melatonin, a sleep-related hormone, increases. That can cause symptoms of depression, including excessive sleeping, difficulty getting out of bed and cravings for carbohydrates.

WHAT CAN YOU DO?
Food: Oh, that Mother Nature. She wants us to plump up in the winter, and so she deliberately delays the feeling of fullness. Carbohydrates beckon because they provide an amino acid called tryptophan, which is used in the production of serotonin, the "happy" brain chemical.

Nutritionists suggest that we aim for a balanced, varied diet, including low-fat foods, fresh fruit and vegetables. Whole-grain carbohydrates release their energy more slowly and can help to balance serotonin levels.

Light boxes: Ask your doctor about getting a commercial light box. Exposure to bright light stimulates the production of serotonin, which is lower in winter. Light intensity is measured by a unit called a lux. We are typically exposed to 50 to 500 lux in the home and workplace or 2,000 lux outside on a rainy winter day. In contrast, specially designed light boxes emit up to 10,000 lux. The treatment consists of sitting two to three feet away and allowing the light to shine directly in the eyes. The boxes cost $300 and up and are said to work for eight out of 10 people.
 

Jody Lemke "I take the sun very personally. It's not the warmth I crave. I am not a summer person. It's the light. I think that's why I spend so much time in our family room during the winter. Our pure white walls are swathed in artificial daylight from an almost obscene number of can lights. They actually heat the room. I don't turn them all on for the heat, however, but for the false sense of sunshine." Jody Lemke, Seattle essay writer.

Exercise: Get outside. We need at least two hours of light exposure a day to function normally. One study found that an hour's walk in winter sunlight was as effective as 2-1/2 hours under bright, artificial light.

Gee-whiz facts

• The ability to handle the dark could be in your DNA. Since the incidence of SAD increases with latitude up to a point but not all the way to the poles, we may adapt genetically. People who move from Iceland down to Canada seem to have a lower incidence than the natives. Vice versa, people who move up from the Lower 48 to Alaska have a harder time.

• Perhaps because their chemical levels are already fluctuating with monthly cycles, women are four times more likely to develop SAD. The good news is the symptoms seem to decrease after age 50.

• Food consumption by astronauts drops to 70 percent of recommended levels in space, according to a study. One theory is that continuous exposure to light in orbit upsets the circadian clock and subsequent sleep and eating cycles.

Information for this page was gathered from wire services and Web sites, including the National Mental Health Association, Seasonal Affective Disorder Association, beautifulseattle.com, nutritionalconcepts.com, riverdeep.net, psychiatrictimes.com and www.sciencenet.org.uk.

Illustrations by Christine Cox, The Seattle Times

More how-to guides for life