Can Winter Cause Depression?
Many people feel sad when summer wanes, but some actually develop depression with the season’s change. Known as seasonal affective disorder (SAD), this form of depression affects about 1%–2% of the population, particularly women and young people. Symptoms are similar to general depression and include lethargy, loss of interest in once-pleasurable activities, irritability, inability to concentrate, and a change in sleeping patterns, appetite, or both. SAD seems to be triggered by more limited exposure to daylight; typically it comes on during the fall or winter months and subsides in the spring. While experts don’t fully understand the cause of SAD, some speculate that the hormone melatonin, which helps regulate your body’s sleep-wake cycle (circadian rhythm), plays a role. The brain secretes melatonin at night, so longer periods of darkness in the winter months may spur greater production of this hormone. Researchers also believe that the same neurotransmitters implicated in other form
