For about 5 percent of Americans, Seasonal Affective Disorder (SAD) settles in just as winter does and stays around until spring. SAD is a recurrent annual depression characterized by hypersomnia, social withdrawal, overeating, carbohydrate cravings, and a lack of sexual energy. It seems to respond to changes in climate and latitude: about 1.5 percent of Floridians have SAD compared with nearly 10 percent of New Hampshirites. Fourteen percent of US adults suffer from a lesser form of SAD known as the winter blues, which leave them feeling less cheerful, energetic, creative, and productive.

There is no cure, per se, for SAD. The most prominent treatment is light therapy, replacing sunlight with bright artificial light. You need to sit for about 30 minutes in the morning in front of a light box (readily available online), which exposes you to at least 10,000 lux of UV-free cool-white fluorescent or full-spectrum light. 

If you suffer from SAD or the winter blues, your instinct to pull the duvet over your head and sleep the winter away isn?t wrong. Humans evolved to be less active in winter because they needed to save energy when food was scarce, but modern Type A culture never cuts us any slack. 

You deserve that nap.?