Battling the winter blues

Why it matters: Although bouts of winter depression are normal during the darker months, severe seasonal affective disorder (SAD) can be crippling for some.

• A lot of people aren't aware that they have it and that it's very treatable, said David Avery, professor emeritus at the UW School of Medicine and an expert in the mood disorder.
• "People can really suffer," he told Axios. "They don't function as well and they don't enjoy life as much."

What's happening: The reduction in light exposure disrupts the circadian rhythm and changes the balance of mood-altering brain chemicals like serotonin and melatonin.

By the numbers: As many as two-thirds of adults say they experience some SAD symptoms: depression, lethargy, fatigue, difficulty waking, disrupted sleep, increased appetite and weight gain during fall and winter, according to the American Psychiatric Association.

• About 5% of American adults struggle with serious seasonal depression, the psychiatric association reports.
• In Seattle, however, that number could be as high as 8 to 10%, Avery said.
• That's because the effect of light deprivation is more pronounced in northern states, which have shorter days and longer nights in the winter than southern states.

What they're saying: "I know a number of patients who did just fine in Texas or Southern California and now they've moved here and developed it," Avery said.

Be smart: The difference between mild and serious cases of SAD is often measured by the intensity and duration of the symptoms, APA president Petros Levounis told Axios.

• "We don't know why some people are more sensitive to it than others, but some experience a major depressive disorder each winter and others do not," he said, "but are still very different from their summer selves."

What to do: One of the simplest, cheapest and most effective treatments is light therapy: exposure to light from light boxes, dawn simulators and light visors, which helpful for parents and others who can't afford to sit still in the morning, Avery said.

• All of them work by bathing the eyes with light and tricking our brains into thinking the days are longer, he said.
• While most people get the best results from additional light in the early morning, some do better with light therapy in the early evening and a few get the most benefits from both morning and evening exposure, Avery said.

Go deeper: Avery has created a list of tips detailing the best of what he's learned over decades of treating patients and researching the disorder.

• In addition to light therapy, he advocates developing healthy sleep habits, getting regular exercise and placing your work area as close to a window as possible.