Seasonal depression, 'winter blues' and SAD

By comparison, even on the year's shortest day – the winter solstice on Dec. 21 – people in Washington, D.C., wants to get almost 9 hours 30 minutes of daylight; in Miami, 10 hours 31 minutes. In Portland, Oregon, it's 8 hours 42 minutes and in Billings, Montana, 8 hours 40 minutes.

Many find that the season's shorter days and longer nights affect their health. About 5 percent of the population develops seasonal depression, according to Mental Health America. Reduced amounts of daylight trigger the somewhat milder "winter blues" in another 10 to 20 percent, according to the American Academy of Family Physicians. Seasonal affective disorder, or SAD, affects women more often than men; 4 out of 5 people with SAD are women. It also affects people under 30 more often than older people. Symptoms include typical signs of depression ̵

1; such as low energy, sleep problems, changes in appetite and weight, and loss of interest in favorite activities. But with SAD, symptoms come and go with the season. No one knows what causes SAD, but most experts link its development to less exposure to the sun's rays, brought about by shorter days in the fall and winter. This may disrupt your body's internal clock, reduce depression, and reduce your body's serotonin levels, increase melatonin levels and decrease vitamin D levels, affecting your mood. Treatment options include light therapy – sitting in front of a special light box for 20 to 60 minutes a day – as well as behavioral therapy and possibly antidepressants.

If relocation is an option, consider heading south. The closer you are to the equator, the lower your risk for seasonal depression.