7 Signs of Seasonal Affective Disorder

Sleepiness and fatigue

People with SAD tend to feel the need to sleep more during the wintertime—sometimes a lot more. In one study, published in the Journal of Psychosomatic Research in 1994, patients at a SAD clinic averaged about 7.5 hours of sleep in the summer, 8.5 hours in the spring and fall, and nearly 10 hours in the winter.

Just because you’re sleeping more doesn’t mean you'll feel rested, however. Other research has shown that people with SAD experience more insomnia and sleep disturbances, and are more prone to nodding off at work.

Next: Irritability

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