Seasonal affective disorder (SAD) affects about one in 20 people in the U.S., manifesting as feelings of sluggishness, depression, and a desire to hibernate during the winter months. Recognizing the seasonal pattern of these symptoms can lead to self-diagnosis, especially if they dissipate with the arrival of spring. While some experience mild winter blues, others may find their daily lives significantly impacted. Always consult a professional if concerns arise regarding mood changes.